Public Fertility Clinics Research Articles

O-188 Conventional in vitro fertilisation versus intracytoplasmic sperm injection in first cycle patients without severe male factor infertility (INVICSI): a randomised, controlled, open-label, multicentre trial

Abstract Study question Is the cumulative live birth rate (CLBR) after ICSI superior to conventional IVF (c-IVF) in first cycle fertility patients without severe male factor infertility? Summary answer In couples without severe male factor infertility, ICSI does not improve the CLBR compared to c-IVF after transfer of embryos from the first oocyte collection What is known already The ICSI procedure, originally developed for addressing severe male factor infertility, has seen expanded utilisation across various causes of infertility. Large retrospective studies and a recent randomised controlled trial (RCT) demonstrated comparable reproductive outcomes between ICSI and c-IVF in couples without male factor infertility. In approximately half of infertility cases, a male factor is involved, with about one-third attributed to male factor alone. Despite this, ICSI currently constitutes two-thirds of all assisted reproductive technology treatments worldwide Study design, size, duration Open-label, two-armed, multicentre RCT. A sample size of 784 women was required to detect a clinically relevant change of 10 percentage points with 80% power. Accounting for an expected 5% exclusion rate (dropouts and unexpected severely decreased quality sperm samples on the day of oocyte retrieval), 824 women were recruited from six public fertility clinics in Denmark between Nov 29, 2019, and Dec 14, 2022 Participants/materials, setting, methods Eligible participants were women aged 18-42 years and in their first treatment cycle with a partner/donor with normal or lightly to moderately decreased sperm quality. Randomisation was performed in a 1:1ratio between ICSI and c-IVF. The primary outcome was CLBR. Follow-up continued until the primary outcome was achieved or for a minimum of one year after the last participant’s inclusion.The primary outcome was assessed in an intention to treat (ITT) and a per protocol analysis Main results and the role of chance In total, 414 and 410 women were randomised to ICSI and c-IVF, respectively. Results include fresh as well as frozen-thawed embryo transfers from the first oocyte collection and are displayed as ITT. All transfers were elective single embryo transfers or single embryo transfers. The cumulative probability of achieving a live birth for couples/women undergoing ICSI was not different compared to those undergoing c-IVF (CLBR: ICSI 42.0% vs. c-IVF 46.6%, Risk ratio: 0.90, 95% CI: 0.77-1.05). The median time from inclusion to live birth did not differ between ICSI and c-IVF (309 days (IQR 268-378) vs 308 days (IQR 269-356); p = 0.12). Total fertilisation failure was seen in 4.9% of the ICSI group compared to 3.8% in the c-IVF group (Risk ratio: 1.29, 95% CI: 0.68-2.54) Limitations, reasons for caution This study was designed with 80% power to identify a 10% percentage point difference in CLBR between ICSI and c-IVF. We cannot dismiss the possibility of a smaller difference between the two methods Wider implications of the findings Our study, supported by prior research, shows that c-IVF rather than ICSI should be the first choice in initial cycles for patients without severe male factor infertility. Fertility staff should inform first cycle patients that ICSI does not increase the live birth rate for couples without severely decreased sperm quality Trial registration number NCT04128904

Rectal versus vaginal progesterone administration for luteal phase support in the hormone replacement therapy frozen embryo transfer (HRT-FET) cycle: protocol for a non-inferiority randomised controlled trial

IntroductionThis study compares rectal administration with vaginal administration of progesterone as luteal phase support in hormone replacement therapy frozen embryo transfer (HRT-FET) cycles. The reason for comparing the two routes...

Reproductive sex ending in failure affects sexual health – A qualitative study of men and women attending a fertility clinic

ObjectiveTo explore men’s and women’s experiences regarding their history of sexual health when attending a fertility clinic. MethodsA qualitative study with semi-structured individual interviews was conducted among heterosexual males and females seeking infertility care at a public fertility clinic in Sweden in 2022–2023. The interviews were audio-recorded, transcribed verbatim and analyzed using qualitative content analysis. ResultsEight males and ten females were included. The analysis resulted in an overarching theme: A change from spontaneous to scheduled intercourse affects various aspects of sexual health. In the beginning of the relationship sex had been spontaneous, joyful and satisfying. However, sex was not always unproblematic, and there had been sexual changes. Sex with a reproductive purpose was scheduled according to ovulation, leading to changes in sexual behavior. Increased erectile problems in men and decreased frequency of orgasms in women, and a lack of sexual desire in both, were experienced. Men and women felt pressured to have sex when it became a requirement. Men’s sexual and women’s reproductive failures led to negative emotional reactions, including stress, frustration, disappointment, anxiety and guilt. Sexual and reproductive problems affected the relational well-being, leading to feelings of sharing the burden but also conflicts and sexual avoidance. ConclusionsExperiencing reproductive failures, sexual problems and negative emotional reactions can affect men’s and women’s sexual health. Therefore, an implication for clinical practice among healthcare professionals during evaluation of infertility, is a need to be aware of and ask questions about sexual health after reproductive failures.

Association between the length of in vitro embryo culture, mode of ART, and the initial endogenous hCG rise in ongoing singleton pregnancies.

Is there an association between the length of in vitro culture, mode of ART and the initial endogenous hCG rise, in cycles with a foetal heartbeat after single embryo transfer (ET) and implantation? Both the length of in vitro culture and the mode of ART have an impact on the initial endogenous rise in hCG in singleton pregnancies. Different factors have been identified to alter the kinetics of hCG in pregnancies. Current studies show conflicting results regarding the kinetics of hCG after different types of ART (fresh vs frozen ET (FET)), the inclusion or not of preimplantation genetic testing (PGT), and the length of time in in vitro culture. This was a multicentre cohort study, using prospectively collected data derived from 4938 women (5524 treatment cycles) undergoing IUI (cycles, n = 608) or ART (cycles, n = 4916) treatments, resulting a in singleton ongoing pregnancy verified by first-trimester ultrasound scan. Data were collected from the Danish Medical Data Centre, used by the three participating Danish public fertility clinics at Copenhagen University hospitals: Herlev Hospital, Hvidovre Hospital, and Rigshospitalet, from January 2014 to December 2021. The fresh ET cycles included cleavage-stage (2 or 3 days in vitro) and blastocyst (5 days in vitro) transfers. FET cycles included cleavage-stage (3 days in vitro before cryopreservation) or blastocyst (5 or 6 days in vitro before cryopreservation) transfers. The IUI cycles represented no time in vitro. To attain a comparable interval for serum-hCG (s-hCG), the ovulation induction time was identical: 35-37 h before oocyte retrieval or IUI. The conception day was considered as: the insemination day for pregnancies conceived after IUI, the oocyte retrieval day for fresh ET, or the transfer day minus 3 or 5 as appropriate for FET of Day 3 or 5 embryos. Multiple linear regression analysis was used, including days post-conception for the hCG measurement as a covariate, and was adjusted for the women's age, the cause of infertility, and the centre. For FET, a sensitivity analysis was used to adjust for endometrial preparation. The study totally includes 5524 cycles: 2395 FET cycles, 2521 fresh ET cycles, and 608 IUI cycles. Regarding the length of in vitro culture, with IUI as reference (for no time in in vitro culture), we found a significantly lower s-hCG in pregnancies achieved after fresh ET (cleavage-stage ET or blastocyst transfer). S-hCG was 18% (95% CI: 13-23%, P < 0.001) lower after fresh cleavage-stage ET, and 23% (95% CI: 18-28%, P < 0.001) lower after fresh blastocyst transfer compared to IUI. In FET cycles, s-hCG was significantly higher after blastocyst transfers compared to cleavage-stage FET, respectively, 26% (95% CI: 13-40%, P < 0.001) higher when cryopreserved on in vitro Day 5, and 14% (95% CI: 2-26%, P = 0.02) higher when cryopreserved on in vitro Day 6 as compared to Day 3. Regarding the ART treatment type, s-hCG after FET blastocyst transfer (Day 5 blastocysts) cycles was significantly higher, 33% (95% CI: 27-45%, P < 0.001), compared to fresh ET (Day 5 blastocyst), while there was no difference between cleavage-stage FET (Days 2 + 3) and fresh ET (Days 2 + 3). S-hCG was 12% (95% CI: 4-19%, 0.005) lower in PGT FET (Day 5 blastocysts) cycles as compared to FET cycles without PGT (Day 5 blastocysts). The retrospective design is a limitation which introduces the risk of possible bias and confounders such as embryo score, parity, and ovarian stimulation. This study elucidates how practices in medically assisted reproduction treatment are associated with the hCG kinetics, underlining a potential impact of in vitro culture length and mode of ART on the very early embryo development and implantation. The study provides clinicians knowledge that the type of ART used may be relevant to take into account when evaluating s-hCG for the prognosis of the pregnancy. No funding was received for this study. AP has received consulting fees, research grants, or honoraria from the following companies: Preglem, Novo Nordisk, Ferring Pharmaceuticals, Gedeon Richter, Cryos, Merck A/S, and Organon. AZ has received grants and honoraria from Gedeon Richter. NLF has received grants from Gedeon Richter, Merck A/S, and Cryos. MLG has received honoraria fees or research grants from Gedeon Richter, Merck A/S, and Cooper Surgical. CB has received honoraria from Merck A/S. MB has received research grants and honoraria from IBSA. MPR, KM, and PVS all report no conflicts of interest. The study was registered and approved by the Danish Protection Agency, Capital Region, Denmark (Journal-nr.: 21019857). No approval was required from the regional ethics committee according to Danish law.

Single mothers by choice - experiences of single women seeking treatment at a public fertility clinic in Denmark: A pilot study

ProblemThere has been an increase in the number of single women deciding to have children through the use of medically assisted reproduction (MAR). These women are referred to as ‘single mothers by choice’ (SMC). Background: Previous studies have shown how SMC can feel stigmatised. Aim: Explore if single women seeking fertility treatment in Denmark feel stigmatised. MethodsSix single women undergoing MAR at a public fertility clinic in Denmark were interviewed. The interviews were audiotaped, anonymised, and transcribed in full, after provided written consent by the participants to take part in the study. Data were analysed using qualitative content analysis. FindingsThe women would have preferred to have a child in a relationship with a partner. Despite their dream of the nuclear family meaning a family group consisting of two parents and their children (one or more), the women choose to become SMC because motherhood was of such importance, and they feared they would otherwise become too old to have children. The participants did not experience stigma or negative responses to their decision, but they all had an awareness of the prejudices other people might have towards SMC. ConclusionThis study contributes to the understanding of the experiences of single women seeking fertility treatment in a welfare state where there are no differences in the possibilities for different social classes to seek MAR.

Early pregnancy bleeding after assisted reproductive technology: a systematic review and secondary data analysis from 320 patients undergoing hormone replacement therapy frozen embryo transfer.

Early pregnancy bleeding after assisted reproductive technology: a systematic review and secondary data analysis from 320 patients undergoing hormone replacement therapy frozen embryo transfer.

Rectal progesterone administration secures a high ongoing pregnancy rate in a personalized Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) protocol: a prospective interventional study.

Can supplementation with rectal administration of progesterone secure high ongoing pregnancy rates (OPRs) in patients with low serum progesterone (P4) on the day of blastocyst transfer (ET)? Rectally administered progesterone commencing on the ET day secures high OPRs in patients with serum P4 levels below 35 nmol/l (11 ng/ml). Low serum P4 levels at peri-implantation in Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) cycles impact reproductive outcomes negatively. However, studies have shown that patients with low P4 after a standard vaginal progesterone treatment can obtain live birth rates (LBRs) comparable to patients with optimal P4 levels if they receive additionalsubcutaneous progesterone, starting around the day of blastocyst transfer. In contrast, increasing vaginal progesterone supplementation in low serum P4 patients does not increase LBR. Another route of administration rarely used in ART is the rectal route, despite the fact that progesterone is well absorbed and serum P4 levels reach a maximum level after ∼2 h. This prospective interventional study included a cohort of 488 HRT-FET cycles, in which a total of 374 patients had serum P4 levels ≥35 nmol/l (11 ng/ml) at ET, and 114 patients had serum P4 levels <35 nmol/l (11 ng/ml). The study was conducted from January 2020 to November 2022. Patients underwent HRT-FET in a public Fertility Clinic, and endometrial preparation included oral oestradiol (6 mg/24 h), followed by vaginal micronized progesterone, 400 mg/12 h. Blastocyst transfer and P4 measurements were performed on the sixth day of progesterone administration. In patients with serum P4 <35 nmol/l (11 ng/ml), 'rescue' was performed by rectal administration of progesterone (400 mg/12 h) starting that same day. In pregnant patients, rectal administration continued until Week 8 of gestation, and oestradiol and vaginal progesterone treatment continued until Week 10 of gestation. Among 488 HRT-FET single blastocyst transfers, the mean age of the patients at oocyte retrieval (OR) was 30.9 ± 4.6 years and the mean BMI at ET 25.1 ± 3.5 kg/m2. The mean serum P4 level after vaginal progesterone administration on the day of ET was 48.9 ± 21.0 nmol/l (15.4 ± 6.6 ng/ml), and a total of 23% (114/488) of the patients had a serum P4 level lower than 35 nmol/l (11 ng/ml). The overall, positive hCG rate, clinical pregnancy rate, OPR week 12, and total pregnancy loss rate were 66% (320/488), 54% (265/488), 45% (221/488), and 31% (99/320), respectively. There was no significant difference in either OPR week 12 or total pregnancy loss rate between patients with P4 ≥35 nmol/l (11 ng/ml) and patients with P4 <35 nmol/l, who received rescue in terms of rectally administered progesterone, 45% versus 46%, P = 0.77 and 30% versus 34%, P = 0.53, respectively. OPR did not differ whether patients had initially low P4 and rectal rescue or were above the P4 cut-off. Logistic regression analysis showed that only age at OR and blastocyst scoring correlated with OPR week 12, independently of other factors like BMI and vitrification day of blastocysts (Day 5 or 6). In this study, vaginal micronized progesterone pessaries, a solid pessary with progesterone suspended in vegetable hard fat, were used vaginally as well as rectally. It is unknown whether other vaginal progesterone products, such as capsules, gel, or tablet, could be used rectally with the same rescue effect. A substantial part of HRT-FET patients receiving vaginal progesterone treatment has lowserum P4. Adding rectally administered progesterone in these patients increases the reproductive outcome. Importantly, rectal progesterone administration is considered convenient, and progesterone pessaries are easy to administer rectally and of low cost. Gedeon Richter Nordic supported the study with an unrestricted grant as well as study medication. B.A. has received unrestricted grant from Gedeon Richter Nordic and Merck and honoraria for lectures from Gedeon Richter, Merck, IBSA and Marckyrl Pharma. P.H. has received honoraria for lectures from Gedeon Richter, Merck, IBSA and U.S.K. has received grant from Gedeon Richter Nordic, IBSA and Merck for studies outside this work and honoraria for teaching from Merck and Thillotts Pharma AB and conference expenses covered by Merck. The other co-authors have no conflict of interest to declare. EudraCT no.: 2019-001539-29.

Psychosocial wellbeing shortly after allocation to a freeze-all strategy compared with a fresh transfer strategy in women and men: a sub-study of a randomized controlled trial.

Psychosocial wellbeing shortly after allocation to a freeze-all strategy compared with a fresh transfer strategy in women and men: a sub-study of a randomized controlled trial.

O-024 Exploring the optimal transfer day of day 6 (D6) vitrified blastocysts in Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) cycles - a cohort study

Abstract Study question Should blastocysts cryopreserved D6 be transferred on the 5th or 6th day of progesterone administration in HRT-FET cycles? Summary answer No significant differences in outcome parameters were found when D6 vitrified blastocysts were transferred on either day 5 or day 6 of progesterone in HRT-FET. What is known already Several studies have shown that D6 blastocyst transfer should be avoided in fresh transfer IVF cycles; consequently, these more slowly developing embryos are transferred in a HRT-FET cycle on the 6th day of progesterone administration in line with day 5 (D5) blastocysts. For successful implantation, a receptive endometrium and optimal synchronization between the endometrium and embryo are important. However, no definitive evidence exists regarding the optimal timing of transferring D6 blastocysts. Interestingly, a few studies have reported better reproductive outcomes if D6 blastocysts are transferred on the 5th day of progesterone administration instead of the 6th day of progesterone administration. Study design, size, duration This cohort study included a total of 718 vitrified D6 single blastocyst HRT-FET cycles performed between 2013 and 2022. 576 blastocysts were transferred on the 6th day of progesterone administration (2013-2021), and 142 blastocysts transferred on the 5th day of progesterone administration (2021-2022). Main outcomes were biochemical pregnancy rate (PR), implantation rate (IR), clinical pregnancy rate (CPR), and early pregnancy loss rate (EPLR). Participants/materials, setting, methods Patients undergoing HRT-FET in a public Fertility Clinic. Endometrial preparation included oral oestradiol (6mg/24hours), followed by vaginal micronized progesterone. As mentioned above, single blastocyst transfer was performed on either the 5th or 6th day of progesterone administration. Serum β-hCG level was measured 9-11 days after embryo transfer and biochemical pregnancy was defined as an hCG level &amp;gt;10 IU/L. Clinical pregnancy was defined as visualization of a gestational sac and fetal heartbeat in gestational week 7. Main results and the role of chance In this cohort of a total of 718 HRT-FET cycles transferred on either the 5th or 6th day of progesterone administration the mean age of the patients at embryo transfer was 34.5±4.5 years vs. 33.0±4.9 years, respectively, p = 0.30. There was no significant difference between numbers of top-quality blastocyst transfers within the two groups 63% (89/142) vs. 64% (369/576), p = 0.76. The overall, biochemical pregnancy rate (PR), implantation rate (IR), clinical pregnancy rate (CPR) and early pregnancy loss (EPLR) in the group of patients transferred on the 5th day of progesterone administration were 38% (54/142), 29% (41/142), 25% (36/142) and 33% (18/54). In the group of patients transferred on the 6th day of progesterone administration 41% (235/576), 33% (191/576), 30% (170/576) and 28% (65/235). There were no significant differences between PR, IR, CPR and EPLR when transferring D6 vitrified blastocysts on either the 5th or the 6th day of progesterone administration (38% vs. 41%, p = 0.53, 29% vs. 33%, p = 0.33, 25% vs. 30%, p = 0.33 and 33% vs. 28%, p = 0.41). Limitations, reasons for caution Limitations of the study are the retrospective design and the limited number of D6 vitrified blastocysts transferred on the 5th day of progesterone administration. Furthermore, the two groups represented two different time periods. Wider implications of the findings Growing evidence shows that D5 vitrified blastocysts have better reproductive outcomes than slower developing embryos which are vitrified on day 6. Whether this is caused by intrinsic embryonic factors or poor timing of transfer in a subsequent FET cycle still needs to be unraveled. Trial registration number not applicable

P-555 Do IVF patients prefer the rectal route to the vaginal for luteal phase progesterone administration? - a cohort study

Abstract Study question How do IVF patients perceive rectal administration of progesterone for luteal phase support compared to vaginally administered progesterone? Summary answer Rectal administration of progesterone causes less discomfort in IVF patients, undergoing Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) and is preferred compared to vaginal administration. What is known already Progesterone is essential for implantation and normal development of pregnancy in spontaneous pregnancies as well as in ART pregnancies. In IVF, progesterone is most often administered vaginally in Europe for luteal phase support, although, this route may cause cumbersome discharge, vaginal bleeding, and irritation of the vulva. For many years the vaginal route has been the gold standard, although, progesterone is well absorbed rectally and recent studies have shown that rectally administered micronized progesterone was well accepted among IVF patients. Until now, in IVF very little focus has been on patient convenience as regards luteal phase support. Study design, size, duration An interventional cohort study, conducted from January 2020 to November 2022 in a public fertility clinic. A total of 479 patients received a questionnaire (Q1) by e-mail during the period between the embryo transfer and the pregnancy test; A second questionnaire (Q2) was answered at the time of the first ultrasound scan in gestational week 7. Participants/materials, setting, methods Patients underwent an HRT-FET protocol, including vaginal progesterone (VP) (400mg/12hours). In patients with serum progesterone levels lower than 11 ng/ml on the 6th day of progesterone, additional progesterone was administered rectally (RP) (400mg/12hours) from that day until the day of pregnancy testing, and in pregnant patients until the first scan in week 7. Side effects and patient convenience of both routes were reported in a questionnaire, including 27 questions, using a visual analog scale (0-100). Main results and the role of chance A total of 73% of HRT-FET patients (349/479) answered Q1 before the pregnancy test and a total of 27 % (93/349) of the cohort received progesterone both vaginally and rectally. The response rate of Q2 in gestational week 7 was 100 % (221/221) and a total of 28 % of patients (62/221) administered progesterone both vaginally and rectally. In Q1, a total of 60% of patients (54/90) preferred RP over VP in the cohort of patients treated with both administration regimens. In Q2, a total of 62% of patients (37/60) preferred RP over VP in the cohort of patients treated with both administration regimens. The overall discomfort was lower in relation to RP in both questionnaires and, especially discharge was lower in RP compared to VP; median interquartile range (IQR) in Q1: 11 (3-23) vs. 50 (25-66) and Q2: 19 (9-28) vs. 47 (22-62), respectively. Changes in defecation pattern after RP were reported in Q1 as well as Q2, 48% (45/92) and 55% (34/61), however, the discomfort was reported as mild. An increased flatulence was reported by 50% (46/92) in Q1 and 63% (39/92) in Q2, however, again the discomfort was reported as mild. Limitations, reasons for caution Currently, it is unknown whether the present results apply to progesterone products other than the one used in the present study (Cyclogest®). The questionnaire used, although having been used in another published study with another progesterone product, was not specifically validated for this product. Wider implications of the findings The rectal route should be remembered for luteal phase support in IVF, and some patients might choose the rectal route over the vaginal for their luteal phase support due to less discharge. Trial registration number EudraCT no.: 2019-001539-29

P-493 Bleeding during early pregnancy after Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) – is it more common than we think?

Abstract Study question How common is bleeding in early pregnancy after HRT-FET? And does bleeding affect the reproductive outcome in this population? Summary answer A total of 47% of HRT-FET patients experience bleeding before the 8th week of gestation, however, bleeding does not seem to affect the reproductive outcome. What is known already Bleeding occurs in 20% of spontaneously conceived pregnancies. Most pregnancies will proceed to term although episodes of heavy bleeding are associated with an increased risk of miscarriage. The prevalence of bleeding after assisted reproductive technology including in vitro fertilization seems to be higher and, in some reports, up to 36%. However, the knowledge is scanty and in particular the knowledge regarding bleeding during HRT-FET is sparse. As HRT-FET in clinical practice increases, knowledge on the occurrence of early bleeding during pregnancy and the impact on the reproductive outcome in this population is needed. Study design, size, duration We performed a cohort study including 489 patients undergoing HRT-FET. The trial was conducted from January 2020 to November 2022 in a public fertility clinic. Participants/materials, setting, methods Patients with autologous vitrified blastocyst were treated in a standard HRT-FET protocol. In the event of a positive HCG-test an early pregnancy scan was performed around 8 weeks of gestation. During this visit the women answered a questionnaire covering pregnancy related symptoms, wellbeing, and if bleeding occurred, the type and duration of the bleeding. The information was verified through medical files. Main results and the role of chance In this HRT-FET cohort we found that a total of 47% (150/322) of patients with a positive pregnancy test experienced bleeding before 8 weeks of gestation. Mostly the bleeding was described as spotting with a median of 2 days (range 0.5—16 days). Out of 150 patients with one or several bleeding episodes, a total of 107 patients (71 %) had an ongoing pregnancy at 12 weeks of gestation. In comparison, 172 patients reported no bleeding episodes and a total of 115 (67%) of these patients had an ongoing pregnancy at 12 weeks of gestation. This difference was found to be non-significant (p = 0,39). Limitations, reasons for caution The patients in our study were treated in a standard HRT-FET protocol. The results may not be transferable to other treatment protocols. Also the data is based on patients self-reported symptoms. Therefore some degree of recall bias may be present. Wider implications of the findings Episodes of early bleeding during pregnancy are associated with distress for the pregnant woman – especially in previously infertile patients. Knowledge about the frequent occurrence of bleeding during early pregnancy after HRT-FET and that this does not affect the reproductive outcome will help the clinician reassure and guide the patient. Trial registration number 2019-001539-29

P-596 Rectal progesterone administration secures high ongoing pregnancy rate in a personalized Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) protocol - a prospective interventional study

Abstract Study question Can supplementation with additional rectal administration of progesterone secure high ongoing pregnancy rates (OPR) in patients with low serum progesterone (P4) at blastocyst transfer (ET)? Summary answer Rectally administered progesterone starting on the blastocyst transfer day secures high OPR in patients with serum P4 levels lower than 35 nmol/l (11ng/ml). What is known already Low serum P4 levels at peri-implantation in HRT-FET cycles impact reproductive outcomes negatively. However, studies have shown that patients with low P4 after a standard vaginal progesterone treatment can obtain live birth rates (LBR) comparable to patients with optimal P4 levels if they receive additional subcutaneous progesterone, starting close to the day of blastocyst transfer. In contrast, increasing vaginal progesterone supplementation in low serum P4 patients does not increase LBR. Another route of administration rarely used in ART is the rectal route, although progesterone is well absorbed and serum P4 levels reach a maximum level after approximately two hours. Study design, size, duration This prospective interventional study included a cohort of 488 patients treated with single blastocyst HRT-FET, in which a total of 374 patients had a serum P4 level ≥35nmol/l (11ng/ml) at ET, and 114 patients had a serum P4 level &amp;lt;35nmol/l (11ng/ml). The study was conducted from January 2020 to November 2022. Participants/materials, setting, methods Patients undergoing HRT-FET in a public Fertility Clinic. Endometrial preparation included oral oestradiol (6mg/24hours), followed by vaginal micronized progesterone, 400mg/12hours. Single blastocyst transfer and P4 measurements were performed on the 6th day of progesterone administration and patients with serum P4 &amp;lt;35nmol/l (11ng/ml) additional rectal administration of progesterone (400mg/12hour) was started the same day. In pregnant patients, vaginal and rectal administration continued until week 8, and oestradiol and vaginal progesterone treatment continued until week 10. Main results and the role of chance Among 488 HRT-FET single blastocyst transfers, the mean age of the patients at oocyte retrieval (OR) was 30.9 ±4.6 years and the mean BMI at ET 25.1 ±3.5 kg/m2. The mean serum P4 level after vaginal progesterone administration on the day of blastocyst transfer was 48.9 ±21.0 nmol/l (15.4 ±6.6ng/ml), and a total of 23% (114/488) of the patients had a serum P4 level lower than 35nmol/l (11ng/ml). The overall, positive hCG rate, clinical pregnancy rate, OPR week 12, and total pregnancy loss rate were 66% (320/488), 54% (265/488), 45% (221/488), and 31% (99/320), respectively. There was no significant difference in neither OPR week 12 nor total pregnancy loss rate between patients with P4 ≥35nmol/l (11ng/ml) and patients with P4 &amp;lt;35nmol/l, who received rescue in terms of rectally administered progesterone, 45% vs. 46%, p = 0.77 and 30% vs. 34%, p = 0.53, respectively. OPR did not depend on whether patients had initially low P4 and rectal rescue or were above the P4 cut-off. Logistic regression analysis showed that only age at OR and blastocyst scoring correlated with OPR week 12, independently of other factors like BMI, and vitrification day of blastocysts (day 5 or 6). Limitations, reasons for caution In this study vaginal progesterone (Cyclogest®), a solid pessary with progesterone suspended in vegetable hard fat, was used vaginally as well as rectally. It is unknown whether other vaginal progesterone products could be used rectally as easily with the same rescue effect. Wider implications of the findings A substantial part of HRT-FET patients receiving vaginal progesterone treatment has low serum P4. Adding rectally administered progesterone in these patients increases the reproductive outcome. Importantly, rectal progesterone administration is considered convenient by the majority of patients; moreover, progesterone pessaries are easy to administer rectally and of low cost. Trial registration number EudraCT no.: 2019-001539-29

P-551 Association between the length of in vitro culture and mode of ART and the initial se-hCG rise in ongoing singleton pregnancy

Abstract Study question Does the length in vitro and mode of ART (fresh and frozen cycles) impact the se-hCG rise in cycles with ongoing single implantation pregnancy? Summary answer Length in vitro and mode of ART alter the hCG. Blastocysts in FET induced higher hCG than FET clevage stage embryos and fresh blastocyst transfers. What is known already Human chorionic gonadotropin (hCG) is produced by placental trophoblasts providing the first measurable sign of pregnancy. Factors, such as multiple pregnancies, advanced maternal age and gender of the fetus are known to influence hCG levels. Other factors such as mode of ART and length in vitro have been considered to alter the hCG kinetics but with conflicting results. Some studies have shown that hCG levels are higher after fresh blastocyst transfer compared with fresh cleavage stage embryo transfer (ET). Other studies found frozen-thawed embryo transfer (FET) results in higher hCG compared with fresh ET, other studies concluded the opposite. Study design, size, duration Multicenter historical cohort study based on clinical data. The study included 5271 women undergoing in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), insemination (IUI) or FET with single ET followed by hCG measurement day 15-19 after ovulation induction (IVF/ICSI/IUI/natural cycle FET) or progesterone administration (estrogen/progesterone substituted FET cycles). All included cycles resulting in single implantation and ongoing pregnancy verified by ultrasound in week 7-8. Data was collected between January 2014 and December 2021. Participants/materials, setting, methods Data was prospectively collected from the Danish Medical Data Centre used by three public fertility clinics, Copenhagen University hospitals. The association between length in vitro (no in vitro period (IUI), day2/3, day5, day6) and mode of ART (IVF/ICSI, FET) and the initial hCG rise was tested both with linear regression and multivariable regression. The results were based on mean serum hCG and presented in percentage with the corresponding 95% confidence interval (CI). Main results and the role of chance After accounting for the pre-defined exclusion criteria (i.e. oocyte donation, pre-implantation genetic testing, more than one gestational sac), 5251 cycles were included in the study. 2122 were FET, 2521 were fresh ET and 608 were IUI. The initial hCG rise was overall lower for fresh ET compared to IUI (no in vitro period). For cleavage stage ET, hCG was 18% (95% CI: 13% - 23%, p &amp;lt; 0.001) lower, and for blastocyst transfer 23% (95% CI: 18% - 28%, p &amp;lt; 0.001) lower. In FET, hCG was 26% (95% CI: 13% - 40%, p &amp;lt; 0.001) higher for blastocyst transfer compared to cleavage stage ET. When comparing blastocyst transfer in FET vs. fresh ET cycles, hCG was 33% (95% CI: 27% - 45%, p &amp;lt; 0.001) higher in FET cycles. Stratifying FET cycles in natural and substituted cycle did not alter the result. All results remained significant after adjusting for referral diagnosis, women age and treatment center. Limitations, reasons for caution It cannot be excluded that the higher level of hCG in IUI pregnancies is due to an additional vanished implantation. Wider implications of the findings The mechanisms in the embryo and endometrial interplay are far from understood. The present data add to the knowledge regarding this, pointing towards alteration in the implantation window in fresh stimulated cycles. Studies following the more detailed hCG rise are needed for further elucidating how ART affect the early implantation. Trial registration number Journal-nr.: 21019857

P-595 What to expect from “standard vaginal progesterone regimen” in Hormone Replacement Therapy Frozen Embryo Transfer (HRT-FET) – do different products result in different serum levels?

Abstract Study question Do luteal serum progesterone levels (P4) vary in relation to time of blood sampling, the type and dosing of vaginal progesterone products used for HRT-FET? Summary answer Significant differences in luteal serum P4 levels exist between time of blood sampling as well as between different vaginal progesterone products and the administration regimen. What is known already Mid-luteal P4 levels below 9-11 ng/ml have been shown to negatively affect reproductive outcomes in HRT-FET cycles. Formulations of vaginal progesterone products differ as progesterone can be suspended in vegetable hard fat, in a vegetable lipophile liquor, be prepared in an oil-in-water emulsion carrier, or mixed in a tablet. Moreover, dosing regimens vary from one to three times daily, and BMI, age, and parity affect serum P4 levels; importantly, no consensus exists in terms of optimal time point to measure P4 in relation to administration, the specific serum P4 cut-off level to use or the most optimal vaginal progesterone product. Study design, size, duration Cohort study including 488 HRT-FET blastocyst transfers performed from January 2020 to November 2022 in patients undergoing a “standard vaginal progesterone regimen”. Each patient participated only once in the study. To compare the vaginal progesterone product used in the present study, we reviewed the most recent literature, including data from six studies, using three different products in six different regimens; all studies were cohort studies, including between 227 -1150 patients undergoing a “standard” HRT-FET protocol. Participants/materials, setting, methods A total of 488 patients in a public Fertility Clinic underwent HRT-FET, including endometrial preparation with oral oestradiol (6mg/24hours), followed by vaginal micronized progesterone, 400mg/12hours (Cyclogest®). Blood sampling on the blastocyst transfer day was standardised to two to four hours after progesterone administration. In contrast, P4 was measured randomly on the day of pregnancy testing. For comparison a review of the literature from six HRT-FET cohort studies using either Crinone®, Utrogestan® or “PIVET”-pessaries was performed. Main results and the role of chance The mean serum P4 (2-4 hours after administration) on the day of blastocyst transfer in our cohort was 15.4 ±6.6ng/ml. On the day of pregnancy testing (random time points) serum P4 levels were divided into four groups, depending on the time from progesterone administration to blood sampling: &amp;lt;2hours, &amp;gt;2&amp;lt;4hours &amp;gt;4&amp;lt;6hours and &amp;gt;6hours.The mean P4 levels were 14.7 ±6.3ng/ml, 15.6 ±5.8ng/ml, 14.3 ±4.9ng/ml and 12.9 ±6.4, respectively, and a significant difference was seen, between P4 levels measured 2-4 hours and &amp;gt;6 hours after vaginal administration (p = 0.03). As regards the product, the mean P4 levels in this study (Cyclogest®) was significantly different from the reviewed P4 levels of other “standard” HRT-FET cohorts, using three different products (Uterogestan®, Crinone® and the “PIVET-pessary”) 12.1 ±7.0ng/ml (p &amp;lt; 0.001), 7.6 ±3.2ng/ml (p &amp;lt; 0.001) and 29.3 ±20.3ng/ml (p &amp;lt; 0.001), respectively. As regards the dose, a significant difference in P4 levels was seen between dosing regimens in two cohorts when using the same product (Crinone®) 90mg x 3 vs. 90 mg x 2; 11.3 ±4.7ng/ml and 7.6 ±3.2ng/ml, respectively, p &amp;lt; 0.001. Interestingly, when comparing another product (Utrogestan®) used in different dosing regimens, 400mg x 2 vs. 200mg x 3, no difference in P4 levels was seen, 12.1 ±7.0ng/ml and 11.3 ±5.1ng/ml, P = 0.09. Limitations, reasons for caution In HRT-FET serum P4 levels reflect the exogenous administration, only, and P4 fluctuations depend on the route and number of administrations, as well as absorption and metabolization. The reviewed data used for this comparison between different progesterone products and regimens derive from cohorts with different characteristics and blood sampling timings. Wider implications of the findings Luteal serum P4 measurement is important, however, standardization of blood sampling in relation to the latest vaginal progesterone administration is mandatory to obtain correct levels. Clinicians should be aware of the significant differences in P4 levels related to dose and vaginal absorption between different types of vaginal progesterone products. Trial registration number EudraCT no.: 2019-001539-29

Anxiety and depression in women with asthma prior to fertility treatment

ABSTRACT Objective We investigate symptoms of anxiety and depression among women with asthma prior to fertility treatment. Methods This is a cross-sectional study of women screened for eligibility to the PRO-ART study (RCT of omalizumab versus placebo in asthmatic women undergoing fertility treatment (NCT03727971)). All participants were scheduled for in vitro fertilization (IVF) treatment at four public fertility clinics in Denmark. Data on demographics and asthma control (ACQ-5) were obtained. Symptoms of anxiety and depression were assessed using the Hospital Anxiety and Depression Scale (HADS-A and D, respectively) and defined as being present on both subscales if a score >7 was obtained. Spirometry, diagnostic asthma test, and measurement of fractional exhaled nitric oxide (FeNO) were conducted. Results A total of 109 women with asthma were included (mean age 31.8 ± 4.6 and BMI 25.5 ± 4.6). Most women had male factor infertility (36.4%) or unexplained infertility (35.5%). Twenty-two percent of the patients reported uncontrolled asthma (ACQ-5 score > 1.5). The mean HADS-A and HADS-D scores were 6.0 ± 3.8 (95% CI 5.3–6.7) and 2.5 ± 2.2 (95% CI 2.1–3.0), respectively. Thirty (28.0%) women reported anxiety symptoms, and four (3.7%) had concomitant depressive symptoms. Uncontrolled asthma was significantly associated with both depressive (p = 0.04) and anxiety symptoms (p = 0.03). Conclusions More than 25% of women with asthma prior to fertility treatment had self-reported symptoms of anxiety, and just below 5% had self-reported depressive symptoms, possibly related to uncontrolled asthma.

Binucleated embryos at the two-cell stage show higher blastocyst formation rates and higher pregnancy and live birth rates compared to non-multinucleated embryos

How does nucleus status at the two-cell stage predict blastocysts formation and clinical outcome after single blastocyst transfer? Binucleated embryos at the two-cell stage (2BI) show higher rates of good quality blastocyst formation, pregnancy and live birth compared to those with one nucleus in each blastomere (2MONO), whereas true multinucleated embryos at the two-cell stage (2MULTI) show lower rates of good quality blastocyst formation and pregnancy compared to 2MONO embryos. The introduction of time-lapse culture has made it possible to study nucleus status at the two-cell stage more consistently and it shows that multinucleation at the two-cell stage (2MN) is a common event. The effect of 2MN is still unclear. High numbers of 2MN with the potential to develop to blastocysts that become clinical pregnancies and result in birth of healthy babies with no impaired perinatal outcome have been reported. However, some studies have found 2MN to be associated with impaired implantation and live birth. Furthermore, knowledge on how the different subgroups of multinucleation affects the IVF outcome is limited. A non-interventional retrospective study was performed in a public fertility clinic. Blastocyst formation data from 223 women attending their first IVF cycle between May 2016 and December 2018, and clinical outcome data from 1314 single blastocyst transfers between May 2014 and December 2018 were used for the study. Fresh and frozen-thawed embryo transfers were included. Embryos were cultured until the blastocyst stage in a time-lapse incubator and nucleus status at the two-cell stage, the Gardner score and other morphokinetic parameters were annotated. We compared blastocyst development and clinical outcome, including positive hCG, ongoing pregnancy and live birth, of embryos with 2BI and/or 2MULTI blastomeres to 2MONO embryos. Embryos with 2BI in one blastomere (2BI1) were twice as likely to develop to good quality blastocysts (odds ratio (OR) 2.54, 95% CI 1.30-4.95, P = 0.006) compared to 2MONO embryos. Embryos with 2MULTI in both blastomeres (2MULTI2) were significantly less able to develop to good quality blastocysts (OR 0.38, 95% CI 0.23-0.63, P < 0.001) compared to 2MONO embryos. Embryos with 2BI in both blastomeres (2BI2) had a significantly better chance of resulting in a positive hCG (OR 2.40, 95% CI 1.11-5.20, P = 0.027), ongoing pregnancy (OR 2.79, 95% CI 1.29-6.04, P = 0.009) and live birth (OR 3.16, 95% CI 1.43-6.95, P = 0.004) compared to 2MONO blastocysts after single blastocyst transfer. In contrast, 2MULTI2 embryos were significantly less likely to result in a positive hCG (OR 0.58, 95% CI 0.35-0.97, P = 0.036) and ongoing pregnancy (OR 0.51, 95% CI 0.28-0.94, P = 0.030) compared to 2MONO blastocysts. Discrepancies among the existing studies regarding the definition of multinucleation may lead to different conclusions. Even though the distinction between binucleation and true multinucleation was a strength in our study design, a further distinction between true multinucleated and micronucleated embryos could be interesting to investigate in future studies. Also, we included any anucleated embryos in the 2MONO group. For the study of clinical outcomes, the patients were allowed to be included with more than one transfer cycle. Both fresh and thawed transfers were included. We find it important to discriminate between binucleation and true multinucleation when evaluating embryo nucleus status at the two-cell stage. Embryos displaying 2BI1 and 2BI2 have significantly better good quality blastocyst formation rates and clinical outcome after single blastocyst transfers, respectively. 2MULTI2 embryos have impaired blastocyst development potential and poorer clinical outcomes. H.S.N. received an unrestricted grant from Merck for 3 months' normal salary for a medical Doctor (A.L.T.) to write the manuscript. Merck was not involved in the study design, analysis, interpretation of data, writing the paper or the decision to submit the manuscript for publication. H.S.N. has received speaker's fees from Ferring Pharmaceuticals, Merck Denmark A/S, Astra Zeneca, Cook Medical and Ibsa Nordic (outside the submitted work). N.l.C.F. has received a grant from Gedeon Richter (outside the submitted work). The other authors did not report any potential conflicts of interest. All authors declared no conflicts of interest regarding this work. N/A.

Is paternal age associated with transfer day, developmental stage, morphology, and initial hCG-rise of the competent blastocyst leading to live birth? A multicenter cohort study.

In this study we investigated whether age of men undergoing assisted reproductive technology (ART) treatment was associated with day of transfer, stage, morphology, and initial hCG-rise of the competent blastocyst leading to a live birth? The design was a multicenter historical cohort study based on exposure (age) and outcome data (blastocyst stage and morphology and initial hCG-rise) from men whose partner underwent single blastocyst transfer resulting in singleton pregnancy/birth. The ART treatments were carried out at sixteen private and university-based public fertility clinics. We included 7246 men and women, who between 2014 and 2018 underwent controlled ovarian stimulation (COS) or Frozen-thawed Embryo Transfer (FET) with a single blastocyst transfer resulting in singleton pregnancy were identified. 4842 men with a partner giving birth were included, by linking data to the Danish Medical Birth Registry. We showed that the adjusted association between paternal age and transfer day in COS treatments was OR 1.06, 95% CI (1.00;1.13). Meaning that for every increase of one year, men had a 6% increased probability that the competent blastocyst was transferred on day 6 compared to day 5. Further we showed that the mean difference in hCG values when comparing paternal age group 30-34, 35-39 and 40-45 with the age group 25-29 in those receiving COS treatment, all showed significantly lower adjusted values for older men. In conclusion we hypothesize that the later transfer (day 6) in female partners of older men may be due to longer time spent by the oocyte to repair fragmented DNA of the sperm cells, which should be a focus of future research in men.

Effects of letrozole cotreatment on endocrinology and follicle development in women undergoing ovarian stimulation in an antagonist protocol.

What are the downstream endocrine and paracrine consequences of letrozole (LZ) cotreatment during ovarian stimulation and is follicle growth and recruitment affected? Letrozole cotreatment induces marked changes in both the follicular and luteal phase endocrinology causing potentiation of follicle diameter and an improved corpus luteum function without affecting the secondarily recruited follicle cohort. Letrozole is a third-generation aromatase inhibitor that is well-established as an effective ovulatory agent, while its possible benefits in standard in vitro fertilization protocols are less thoroughly investigated. This study included a double-blinded, placebo-controlled, randomized study with LZ or placebo intervention during ovarian stimulation for IVF treatment, an observational preceding baseline natural cycle and a succeeding follow-up visit. Participants were enrolled between August 2016 and November 2018. Data from the randomized, stimulated cycle were part of a larger RCT, which was previously published. The study was conducted at a public fertility clinic at Herlev Hospital, Denmark, including 31 healthy, normo-responding women eligible for IVF treatment. They underwent a natural baseline cycle and were subsequently randomized to receive either LZ 5 mg (n = 16) or placebo (n = 15) daily during ovarian stimulation from cycle day (CD) 2-3 until induction of ovulation. Throughout both cycles, monitoring was performed every third day with transvaginal ultrasound for assessment of follicle count and diameter, and blood analyses for the determination of twelve endocrine and paracrine parameters. A follow-up assessment was performed at CD2-3 in the succeeding cycle. In the randomized part of the study, we determined differences in blood parameters, follicle recruitment, and follicle diameter. In the observational part of the study, we assessed follicle recruitment in between cycles and its correlation to endocrine parameters. Letrozole cotreatment significantly suppressed oestradiol (E2) concentrations in the follicular phase (area under the curve (AUC) -58% (95% CI [-70%; -43%], P < 0.001)) and luteal phase (AUC -39% [-63%; -1%], P = 0.046). This had a marked effect on the endocrine and paracrine output with increased follicular phase luteinizing hormone (AUC +37% [3%; 82%], P = 0.033), androstenedione (AUC +36% [6%; 74%], P = 0.016), testosterone (AUC +37% [7%; 73%], P = 0.013) and 17-OH-progesterone (AUC +114% [10%; 318%], P = 0.027). Furthermore, follicle-stimulating hormone (FSH) was increased at stimulation day 5 in the LZ group (P < 0.05). In the luteal phase, increased corpus luteum output was reflected by elevated progesterone (AUC +44% [1%; 104%], P = 0.043), inhibin A (AUC +52% [11%; 108%], P = 0.011), androstenedione (AUC +31% [9%; 58%], P = 0.006) and testosterone (AUC +29% [6%; 57%], P = 0.012) in the LZ group. The altered balance between oestrogens and androgens was reflected in a markedly reduced SHBG concentration in the LZ group throughout the luteal phase (AUC -35% [-52%; -11%], P = 0.009). Endocrine and paracrine parameters were similar between groups at the follow-up visit. Letrozole cotreatment significantly increased the mean number of follicles >16 mm at oocyte retrieval (7.2 vs 5.2, difference: 2.0, 95% CI [0.1; 3.8], P = 0.036), while the mean total number of follicles at oocyte retrieval was the same (23.7 vs 23.5, difference: 0.2 [-5.8; 6.1], P = 0.958), and the mean FSH consumption during the stimulated cycle was similar (1500 vs 1520 IU, difference -20 IU [-175; 136], P = 0.794). Between cycles, the mean antral follicle count at CD2-3 was unchanged (natural cycle 19.0, stimulated cycle 20.9, follow-up cycle 19.7, P = 0.692) and there was no effect of LZ cotreatment on the recruitment of the next follicle cohort (test for interaction, P = 0.821). This study included a relatively small, selected group of healthy women with an expected normal ovarian function and reserve, and the effects of LZ may therefore be different in other patient groups. We confirm some previous findings concerning increased follicle growth and increased endogenous FSH and androgen production, which support the rationale for further studies on the use of LZ cotreatment, for example, as a form of endogenous androgen priming sensitizing the follicle to FSH. Letrozole appears to improve the luteal phase with better stimulation of corpus luteum and progesterone secretion. The authors declare no conflicts of interest relating to the present work. NCT02939898.

Predictive performance of peritoneal fluid in the pouch of Douglas measured five days after oocyte pick-up in predicting severe late-onset OHSS: A secondary analysis of a randomized trial

ObjectivesTo investigate if the amount of peritoneal fluid (PF) in the Pouch of Douglas at oocyte pick-up (OPU) or OPU + 5 days predict severe late-onset ovarian hyperstimulation syndrome (OHSS) in women undergoing ovarian stimulation for assisted reproductive technology (ART). Study designA secondary analysis of a dual-centre RCT on 1050 women referred for their first ART treatment in two public fertility clinics in Denmark and randomized 1:1 to GnRH-antagonist or GnRH-agonist protocol. All women from the two arms who were examined on day of OPU and OPU + 5 days were included in this study (n = 940). The ability of PF in the pouch of Douglas to predict severe late-onset OHSS was assessed by multivariate logistic regression analyses and receiver operator characteristics (ROC) curve analyses and compared with other known predictors of OHSS. The final models were cross-validated by the leave-one-out method to assess the models’ generalizability. ResultsA total of 28 (3%) women developed severe late-onset OHSS. PF in the pouch of Douglas measured on OPU + 5 days predicted severe late-onset OHSS. The optimal cut-off value was 17.5 mm at OPU + 5 days with a 61% sensitivity and 71% specificity (Area under the curve = 0.70 95% CI 0.61–0.80). PF on the day of OPU was not predictive of late on-set OHSS as the adjusted multivariate logistic regression analyses showed insignificant results. ConclusionAlthough PF in the pouch of Douglas could predict late-onset severe OHSS, the low sensitivity underlines that it is not useful as a sole marker to decide whether to perform blastocyst transfer or to use a freeze-all strategy.

Idiopathic early ovarian aging: is there a relation with premenopausal accelerated biological aging in young women with diminished response to ART?

To evaluate whether young women with idiopathic early ovarian aging, as defined by producing fewer oocytes than expected for a given age over multiple in vitro fertilization (IVF) cycles, have changes in telomere length and epigenetic age indicating accelerated biological aging (i.e., increased risk of morbidity and mortality). A prospective cohort study was conducted at two Danish public fertility clinics. A total of 55 young women (≤ 37years) with at least two IVF cycles with ≤ 5 harvested oocytes despite sufficient stimulation with follicle-stimulating hormone (FSH) were included in the early ovarian aging group. As controls, 52 young women (≤ 37years) with normal ovarian function, defined by at least eight harvested oocytes, were included. Relative telomere length (rTL) and epigenetic age acceleration (AgeAccel) were measured in white blood cells as markers of premenopausal accelerated biological aging. rTL was comparable with a mean of 0.46 (± SD 0.12) in the early ovarian aging group and 0.47 (0.14) in the normal ovarian aging group. The AgeAccel of the early ovarian aging group was, insignificantly, 0.5years older, but this difference disappeared when adjusting for chronological age. Sub-analysis using Anti-Müllerian hormone (AMH) as selection criterion for the two groups did not change the results. We did not find any indications of accelerated aging in whole blood from young women with idiopathic early ovarian aging. Further investigations in a similar cohort of premenopausal women or other tissues are needed to fully elucidate the potential relationship between premenopausal accelerated biological aging and early ovarian aging.