In Vitro Maturation Cycles Research Articles

A Comparison of Embryonic Development and Clinical Outcomes between In vitro Oocytes Maturation Using Micro-Vibration System and In vivo Oocytes Maturation in Polycystic Ovarian Syndrome Patients

Background/Objectives: Mechanical micro-vibration remains insufficient for improving embryo culture conditions in human immature oocytes. This study compared the clinical outcomes and embryo development between germinal vesicle (GV) oocytes with the micro-vibration culture (MVC) system in in vitro maturation (IVM) cycles and in vivo-matured oocytes in controlled ovarian hyperstimulation (COH) cycles in polycystic ovarian syndrome (PCOS) patients. Methods: This study investigated 152 PCOS patients who underwent 159 fresh embryo transfer cycles, including IVM cycles with embryos derived from GV oocytes and the COH cycles with embryos derived from in vivo-matured oocytes. The IVM cycles were divided into groups according to the culture system used: static culture (SC) and MVC: In the IVM-S group (n = 47), SC was applied during both IVM and in vitro culture (IVC), whereas in the IVM-MV group (n = 44), MVC was applied during both IVM and IVC. For the COH cycles, in the COH-S group (n = 68), SC was applied during IVC. Results: The number of in vitro-matured oocytes was similar in the IVM-S and IVM-MV groups, but the good-quality embryo (GQE; ≥6-cells) rate was significantly higher in the IVM-MV group (p < 0.01). The GQE rate and clinical outcomes of the COH-S group were significantly better than those of the IVM-S group (p < 0.05) but similar to those of the IVM-MV group. Conclusion: Compared with the SC system, the MVC system in IVM cycles improves the embryonic quality of GV oocytes and clinical outcomes, resulting in development of potential equivalent to in vivo-matured oocytes.

Enhancing the scope of in vitro maturation for fertility preservation: transvaginal retrieval of immature oocytes during endoscopic gynaecological procedures.

Could in vitro maturation (IVM) following transvaginal oocyte retrieval during gynaecological surgery (IVM-surgery) be an effective and safe strategy for fertility preservation? IVM-surgery on unstimulated ovaries is a novel option that can be considered for fertility preservation for women requiring gynaecological surgery, but more research is needed to identify appropriate patients who may benefit and to determine the cost-effectiveness of such an approach. IVM followed by oocyte/embryo cryopreservation has been useful as a safe reproductive strategy for some infertile women. This prospective cohort study comprised 158 consecutive women with polycystic ovary syndrome (PCOS) who underwent laparoscopy or hysteroscopy for other reasons and had concomitant transvaginal oocyte retrieval followed by IVM between 2014 and 2016. A total of 158 women with anovulatory PCOS who underwent IVM-surgery in our infertility centre were recruited for this study. Matured IVM oocytes obtained from these women were either freshly fertilized and subsequently frozen at the blastocyst stage (fresh oocyte group, n = 46) or the oocytes were frozen (frozen oocyte group, n = 112) for fertility preservation followed by later thawing for insemination and cleavage embryo transfer (ET) (n = 33). The following outcomes were then evaluated: embryological data, clinical pregnancy rate, live birth rate (LBR), neonatal outcomes, post-operative complications and post-operative ovarian function. Among all the women who underwent IVM-surgery, the clinical pregnancy rate and LBR per initiated IVM cycle were 9.5% (15/158) and 6.9% (11/158), respectively. Women (40.6%, 20/33) who underwent the procedure with frozen-thawed oocytes (oocyte survival rate, 83.0%) obtained a high quality of cleaved embryos. In the fresh oocyte group, the clinical pregnancy rate and LBR per ET cycle were 69.2 and 53.8%, respectively. In the frozen oocyte group, the clinical pregnancy rate and LBR per ET cycle were 28.6 and 19.1%, respectively. No adverse neonatal outcomes were recorded. IVM-surgery was not associated with post-operative complications, a longer hospital stay, or impaired ovarian function. Because of the small sample size and the low utilization rate and cost-effectiveness per retrieval, the present findings should be interpreted with caution, and further studies are needed for the long-term follow-up of live births. This strategy can also help patients with normal ovulation to obtain available oocytes and embryos for cryopreservation and subsequent use. This research was supported by the Joint Research Fund for Overseas Natural Science of China (No. 31429004), the National Key Research and Development Program of China (No. 2017YFC1002000, 2017YFC1001504, 2016YFC1000302), the Ministry of Science and Technology of China Grants (No. 2014CB943203), the Chinese Society of Reproductive Medicine Fund (No. 16020400656) and the National Natural Science Foundation of China (No. 81300456). All the authors have nothing to disclose in terms of conflicts of interest. chictr-ONC-17011861.

Rescue In Vitro Maturation in Polycystic Ovarian Syndrome Patients Undergoing In Vitro Fertilization Treatment who Overrespond or Underrespond to Ovarian Stimulation: Is It A Viable Option? A Case Series Study.

BackgroundThis study intends to present the role of rescue in vitro maturation (IVM) in polycystic ovarian syn- drome (PCOS) patients undergoing in vitro fertilization (IVF) treatment who have inappropriate responses to ovarian stimulation.Materials and MethodsThis was a retrospective case series study of five PCOS patients undergoing IVF treatment considered for cycle cancellation due to increased risk of ovarian hyperstimulation syndrome (OHSS) as group A or poor response to ovarian stimulation as group B. Patients in group A had high oestradiol levels and recruitment of high numbers of small/intermediate sized follicles that did not meet the criteria for human chorionic gonadotropin (hCG) triggering. Patients in group B responded inadequately to hormonal stimulation despite high gonadotropin dosage. Treatment was changed to rescue IVM cycles after the patients provided consent.ResultsIn group A, three IVF patients deemed to have high chances of developing OHSS as evidenced by high oestradiol levels were converted to IVM. A total of the 58/68 oocytes retrieved were mature or matured in vitro. There were 26 cleaving embryos obtained. Two patients had live births and one patient suffered a miscarriage. In group B, rescue IVM was implemented in two patients due to poor ovarian response (POR). A total of 22/26 oocytes retrieved were mature or matured in vitro. There were 13 cleaving embryos obtained. One patient had a live birth, whilst the other suffered a miscarriage.ConclusionRescue IVM could be a viable option in PCOS patients undergoing IVF treatment who are unable to safely meet the criteria for hCG triggering due to overresponse to ovarian stimulation or ovarian resistance to high doses of stimulation. Conversion to IVM can still result in reasonable oocyte retrieval and lead to clinical pregnancy and live births without the risks of OHSS.

Immature Oocyte for Fertility Preservation.

In vitro maturation (IVM) of human immature oocytes has been offered to women who are at risk of developing ovarian hyperstimulation syndrome (OHSS) caused by gonadotropin stimulation, such as PCO(S) patients or who have poor ovarian reserve. Cryopreservation of oocytes matured in vivo obtained in IVF cycles has improved after implementing the vitrification method and many successful results have been reported. Now, this procedure can be successfully offered to fertility preservation programs for patients who are in danger of losing their ovarian function due to medical or social reasons, and to oocyte donation programs. This vitrification technique has also been applied to cryopreserve oocytes obtained from IVM program. Some advantages of oocytes vitrification related with IVM are: (1) eliminating costly drugs and frequent monitoring; (2) completing treatment within 2 to 10 days (3) avoiding the use of hormones in cancer patients with hormone-sensitive tumors; and (4) retrieving oocytes at any point in menstrual cycle, even in the luteal phase. In addition, immature oocytes can also be collected from extracorporeal ovarian biopsy specimens or ovaries during caesarian section. Theoretically, there are two possible approaches for preserving immature oocytes: oocyte cryopreservation at the mature stage (after IVM) and oocyte cryopreservation at the Germinal Vesicle (GV)-stage (before IVM). Both vitrification of immature oocyte before/after IVM is not currently satisfactory. Nevertheless, many IVF centers worldwide are doing IVM oocyte cryopreservation as one of the options to preserve fertility for female cancer. Therefore, more studies are urgently required to improve IVM- and vitrification method to successfully preserve oocytes collected from cancer patients. In this review, present oocyte maturation mechanisms and recent progress of human IVM cycles will be discussed first, followed by some studies of the vitrification of human IVM oocyte.

Aberrant endometrial steroid receptor expression in in-vitro maturation cycles despite hormonal luteal support: A pilot study

Clinical outcomes of fresh embryo transfer in non-hCG triggered in vitro maturation (IVM) cycles are inferior compared to vitrified-warmed embryo transfer. This is a prospective observational pilot study in a consecutive cohort of 31 polycystic ovary syndrome (PCOS) patients and 37 normo-ovulatory egg donors who underwent IVM without fresh embryo transfer between July 2009 and June 2014. All subjects received 150 IU of highly purified menotropin (HP-hMG) daily for three days. On cycle day 6, all patients started transdermal oestradiol (E2) at a daily dose of 9 mg. There was no human chorionic gonadotropin (hCG) trigger before oocyte retrieval (OR). Vaginal micronized progesterone was commenced on the evening after OR, at a daily dose of 600 mg. Additional luteal phase support (LPS) was administered as follows: Group A: no additional LPS; Group B: 1500 IU of hCG administered 4 h after OR and Group C: 5000 IU of hCG administered 4 h after OR + an additional injection of 5000 IU of hCG 1 day before endometrial biopsy. Endometrial biopsy for histology and immunohistochemistry (IHC) was performed on day 5 or 6 after OR. Instead of being downregulated, both PR-B and ERα in endometrial glands and stroma were moderately to strongly expressed in all three protocols, suggesting that the mid-luteal histological signature of endometrial receptivity is deficient in a non-hCG-triggered IVM cycle. Poor clinical outcomes after fresh embryo transfer following IVM are probably related to inappropriate endometrial development which may be linked to the short follicular phase of IVM cycles.

In Vitro Maturation of Oocytes in Women at Risk of Ovarian Hyperstimulation Syndrome-A Prospective Multicenter Cohort Study.

Background:In vitro maturation (IVM) is an artificial reproductive technology in which immature oocytes are harvested from the ovaries and subsequently will be matured in vitro. IVM does not require ovarian hyperstimulation (OH) and thus the risk of ovarian hyperstimulation syndrome (OHSS) is avoided. In this study, we assessed the live birth rate per initiated IVM cycle in women eligible for in vitro fertilization/intracytoplasmic sperm injection (IVF/ ICSI) and at risk for OHSS. Furthermore, we followed women who were not pregnant after IVM and committed to a conventional IVF/ICSI procedure.Materials and Methods:In this multicenter prospective cohort study, we started 76 IVM cycles using recombinant follicle stimulating hormone (rFSH) priming in 68 patients. There were 66 oocyte retrievals, in which a total of 628 oocytes were collected. We incubated the immature oocytes for 24-48 hours and fertilized those that reached metaphase II by ICSI.Results:Three hundred eighty six (61% oocytes) achieved metaphase II. The fertilization rate was 55%. We performed 59 embryo transfers (1.9 embryos per transfer) in 56 women, including 3 frozen embryo transfers. There were four ongoing pregnancies (5.3% per initiated cycle) leading to the birth of a healthy child at term. None of the patients developed OHSS. The ongoing pregnancy rate of the first conventional IVF/ICSI cycle after an unsuccessful IVM cycle was 44%, which was unexpectedly high.Conclusion:We concluded that IVM led to live births but with low effectiveness in our study. Earlier reported IVM success rates are higher which can be caused by a more extended experience in these centers with the intricate laboratory process. However, a possible selection bias in these studies cannot be ruled out. Furthermore, IVM might have a beneficial effect on further IVF/ICSI treatments due to its “ovarian drilling” effect.

In vitro maturation (IVM) of oocytes in patients with resistant ovary syndrome and in patients with repeated deficient oocyte maturation.

To assess the efficiency of IVM in patients with repeated ART failure due to resistant ovary syndrome or due to deficient oocyte maturation. Clinical and laboratory data were obtained retrospectively from 28 patients who underwent 49cycles of IVM between 2010 and 2017; nine patients had resistant ovary syndrome and 19 patients had repeated deficient oocyte maturation. Nine patients with resistant ovary syndrome underwent 24 IVM cycles. In those, an average of 11.5 ± 10.4 cumulus-oocyte complexes (COC) was retrieved, and IVM resulted in 3.4 ± 3.1 mature oocytes. After ICSI and transfer of 23 cleavage-stage embryos, eight pregnancies were obtained, resulting in five healthy live births. The live birth rate was 16.7% per started cycle and 33.3% per patient. Nineteen patients with a history of deficient oocyte maturation underwent 25 IVM cycles. An average of 10.6 ± 9.2 COC was retrieved, and after IVM, 1.3 ± 2.1 oocytes were mature. No mature oocytes were obtained in 11cycles. In ten cycles with mature oocytes, none of them fertilized after ICSI. Out of four cycles with fertilized oocytes, only one good-quality embryo was obtained. No live births were obtained after IVM in patients with a history of deficient oocyte maturation. Based on our experience, IVM is a valuable approach in patients with resistant ovary syndrome, but should not be recommended for patients with deficient oocyte maturation.

The use of in vitro maturation in stimulated antagonist in vitro fertilization cycles of normo-hyperresponder women due to arrested follicular development: A rescue procedure.

Objective: To evaluate the impact of rescue in vitro maturation (IVM) on the clinical outcomes of women with arrested follicular development in stimulated in vitro fertilization (IVF) cycles.Materials and Methods:This is a retrospective review of 13 patients who were evaluated as normo-hyperresponders for ovarian stimulation. The main outcome measure was the clinical pregnancy and livebirth rates. The purpose of gonadotropin stimulation in patients undergoing IVF is to retrieve multiple oocytes by avoiding multifetal gestation and Ovarian Hyperstimulation syndrome (OHSS). The ovarian response to stimulation ranges from poor response to OHSS, which is related to the follicular number and the dose of the gonadotropins used. However, in some cycles of normo-hyperresponder women, follicular development decelerates or ceases. Close follow-up in a daily manner and increasing the dose of gonadotropins did not change the follicular arrest. This clinical situation has two edges; one is cycle cancellation, which has undesired psychological outcomes for women and the IVF team, and second one is the prolongation of the IVF cycle. For such circumstances, IVM may be a valuable option. Stimulated IVF cycles were converted to IVM as a rescue IVM procedure following detailed informed consent of the women who were close to cycle cancellation.Results:Thirteen 13 IVM cycles and their clinical outcomes are presented. Six women achieved pregnancies, but only 4 delivered 5 healthy live born. The other two women had biochemical loss during follow-up.Conclusion:Based on the data obtained, it can be concluded that gonadotropin-stimulated cycles with follicular arrest at the edge of cancellation can be shifted to rescue IVM procedures with reasonable clinical outcomes.

Occurrence of ovarian follicular dominance during stimulation for IVM impacts usable blastocyst yield.

ObjectiveTo evaluate the influence of ovarian follicular dominance on the outcome of oocyte in-vitro maturation.MethodsThis retrospective cohort study included 21 patients with polycystic ovaries or polycystic ovary syndrome (Rotterdam criteria, 2004) subjected to 24 in-vitro maturation (IVM) cycles between October 2015 and January 2017. Patients undergoing IVM received minimal gonadotropin stimulation starting on day 2 or 3 of the cycle; ovum pick-up typically occurred on days 6 to 8. No hCG-trigger shot was given. Following 30h of IVM, mature oocytes were inseminated by ICSI and the resulting embryos cultured up to the blastocyst stage.ResultsOvarian follicular dominance was observed in nine of the 24 IVM cycles. Oocyte IVM yielded an overall maturation rate of 69.3±23.8%, and no difference was observed when the groups with or without a dominant follicle were assessed independently. The rates of fertilization and usable blastocysts per fertilized oocyte, mature oocyte (Metaphase II) or cumulus-oocyte-complex were nearly three times higher (28.7±22.5%) in the group without ovarian follicular dominance. No differences were found in the clinical pregnancy rates attained by the individuals with or without a dominant follicle after 21 vitrified-warmed blastocyst transfer cycles.ConclusionOccurrence of ovarian follicular dominance during hormonal stimulation for in-vitro maturation negatively impacted embryological outcomes. Strategies devised to limit the appearance of ovarian follicular dominance must be further explored.

Predictive factors for live birth after in vitro maturation of oocytes in women with polycystic ovary syndrome.

In vitro maturation (IVM) of human oocytes can be an alternative treatment option to conventional in vitro fertilization. Women with polycystic ovary syndrome (PCOS) are considered the classical candidates for IVM because of the associated ovarian morphology and because IVM diminishes the risk of developing ovarian hyperstimulation syndrome. The objective of this study was to identify predictive factors for live birth in a cohort of women with PCOS who underwent IVM. This retrospective study included 159 patients with PCOS who had IVM cycles in which single or double embryo transfer was performed. The IVM protocol included three days of gonadotropin ovarian stimulation and hCG priming when the leading follicle size was 10-12mm. Collected cumulus-oocyte complexes were cultured for 24h for maturation. Intracytoplasmic sperm injection (ICSI) was used for fertilization. Embryo transfer was performed two days after fertilization. Demographic and clinical parameters were analyzed with logistic regression to identify predictors for live birth. The women's mean age was 27.4years, the mean number of retrieved oocytes was 14, and the live birth rate was 34.6%. The logistic regression revealed the following significant factors for live birth: infertility duration (OR 0.9; 95% CI, 0.82-0.98), number of collected oocytes (OR 1.56; 95% CI, 1.01-3.2), embryo cell number (OR 2.1; 95% CI, 1.4-3.5), and embryo grade (OR 1.84; 95% CI, 1.13-4.2). Infertility duration, oocyte number, embryo cell number, and embryo grade were the most significant predictors for live birth after IVM in PCOS patients. These prognostic factors can be used when planning treatment or counselling patients.

Outcome of gestational surrogacy according to IVF protocol.

Surrogacy remains the only option for having a biologic child for a unique population of women with severe medical conditions. However, no study has looked at surrogacy outcome as a result of the type of ovarian stimulation of the intended mother [controlled ovarian stimulation (COH), modified natural cycle (MNC), and in vitro maturation (IVM)] for oocyte retrieval. This is a retrospective study, including all intended mothers and gestational carriers in a tertiary, university affiliated, medical center, from 1998 to 2016. Fifty-two women underwent 252 oocyte retrieval cycles. The pregnancy outcome of 212 embryo transfer cycles (64 gestational carriers) was reviewed according to the origin of the embryo. The number of retrieved oocytes was significantly higher following COH (n = 132) compared with IVM (n = 58) and MNC cycles (n = 62) (p = 0.013 and p < 0.0001, respectively). Pregnancy rates for embryos transferred according to each protocol were similar. All pregnancies that ended in live births when oocytes from IVM cycles were used derived from transfers of retrieved mature and mixed mature and immature oocytes. Pregnancies that involved embryos derived solely from immature oocytes that further matured in vitro and were transferred to gestational carriers were unsuccessful. MNC protocol is a good option to achieve pregnancy for intended mothers using gestational surrogacy who have contraindications to COH. The yield of IVM cycles in which immature oocytes are retrieved is inconclusive.

Time-lapse imaging reveals differences in growth dynamics of embryos after in vitro maturation compared with conventional stimulation

To study the impact of invitro maturation (IVM) on embryonal development with the use of time-lapse imaging. Retrospective case-control study. University hospital. In total, 294 embryos were cultured after intracytoplasmic sperm injection treatment of three groups: patients with polycystic ovary syndrome (PCOS) and IVM (n = 105; group 1 [G1]), patients after conventional stimulation without PCOS (n = 115; G2) and with PCOS (n = 74; G3). In total, 171 embryos were finally analyzed (57 G1, 65 G2, and 49 G3). Data of 23 PCOS patients (30 IVM cycles) from January 2012 to July 2015 were matched according to age and number of oocytes to patients after conventional stimulation without PCOS (n = 30; 30 cycles) and with PCOS (n = 16; 19 cycles). Markers of embryo development were analyzed at different time points. Pregnancy rates (PRs) and live birth rates (LBRs) were recorded. Morphokinetic differences in embryo development after IVM compared with conventional stimulation with or without PCOS. The rate of good-quality embryos was significantly lower in G1. Embryo development in G1 was significantly accelerated to the time of appearance of two pronuclei but slowed down by the time of reaching 6-cell stage and remained slower compared with embryos of G2 and G3. PRs as well as LBRs did not differ significantly among the study groups. Although growth dynamics of embryos from G1 differ from G2 and G3 and the rate of good-quality embryos was lower in IVM embryos, PRs and LBRs did not differ significantly.

The morphokinetic characteristics of embryos derived from pcos patients

Polycystic ovary syndrome (PCOS) patients are extremely sensitive to stimulation with exogenous gonadotropins and are at an increased risk of developing ovarian hyperstimulation syndrome (OHSS) during ART treatment. Such patients are therefore likely to greatly benefit from using the in vitro maturation (IVM) technique. However, IVM oocytes have been found to exhibit lower viability and developmental potential than in vivo matured oocytes. The objective of this study was to compare morphokinetics of early stage embryos from IVM oocytes to that of mature oocytes obtained after controlled ovarian stimulation (COS) in PCOS patients, while mature oocytes from stimulated non-PCOS ovaries served as a control. Retrospective study. From Jan. 2014 to Dec. 2015, zygotes were divided into three groups according to oocyte maturity and patient characteristics. A total of 66 zygotes derived from 15 IVM cycles in PCOS patients (Group A), 33 zygotes from 8 COS cycles in PCOS (Group B), and 43 zygotes from 10 COS cycles in non-PCOS patients (Group C) were involved. Following ICSI insemination, morphokinetic parameters of each zygote were recorded and evaluated by a time-lapse monitoring system (EmbryoScopeTM). In Group B, embryos developing to the 3-cell and 4-cell stage were significantly slower than those in Group C (39.2 ± 6.6 hours vs. 35.1 ± 67.2 hours, 43.2 ± 7.5 hours vs. 39.5 ± 6.7 hours) (P <0.05). The time for the initiation of the compaction and the time to the morula stage were remarkably shorter in Group A (75.5 ± 13.6 hours, 82.9 ± 8.5 hours) and Group B (74.6 ± 17.6 hours, 83.4 ± 18.9 hours) than in Group C (84.2 ± 7.5 hours, 96.8 ± 8.0 hours) (P <0.05). The time for the initiation of blastulation and the time to full blastocyst stage were significantly shorter in Group A (92.8 ± 7.4 hours, 104.3 ± 9.5 hours) than in Group C (102.6 ± 5.7 hours, 114.4 ± 7.0 hours) (P <0.05). Embryos derived from PCOS patients, regardless of the maturity at oocyte retrieval, showed faster development from the initiation of compaction onwards in comparison to non-PCOS patients. These results suggest that the state of PCOS may cause changes in morphokinetic behavior of early embryos.

Does in vitro maturation (IVM) have an impact on morphokinetic parameters in comparison with IVF?

Polycystic ovarian syndrome (PCOS) patients are at higher risk of ovarian hyper stimulation syndrome (OHSS) due to the high dose of gonadotropin in IVF. To avoid the possibility of OHSS, IVM techniques have been developed and employed in clinical settings. However, IVM delivers lower pregnancy rates and birth rates than IVF. The objective of this study was to assess whether IVM treatment affects embryo development events together with morphokinetic parameters compared with IVF, and to identify the morphokinetic parameters specific to embryos that were suitable for implantation in IVM cycles. Retrospective study. The subjects were 41 couples who underwent 50 cycles of IVM at our clinic, from May, 2013 to Nov., 2015. After the failure of IVM treatment, 12 couples underwent standard IVF treatment. We assessed 194 embryos derived from IVM-ICSI and 48 embryos derived from IVF-ICSI. Their treatment outcomes were analyzed with morphokinetic events (cell division and interval of cell cleavage) by Primovision (vitrolife Sweden), and rate of clinical outcome. Moreover in IVM cycles, these time points were also compared between transferred embryos that implanted or did not implant. IVM zygotes showed significantly lower good quality embryo on day3, blastocyst formation, and good blastocyst rates compared with IVF. There were no differences in time points of cell division (tPNa to t8), pregnancy and abortion rates between the two groups. However, there were significant differences in synchrony of the second cell cycles (t4-t3:S2) (S2:4.5±5.0h vs. 1.4±2.3h, P=0.0002), and the rate of direct cleavage of one to three, or there to five cells was significantly higher in the IVM group (90/194 46.4% vs. 9/48 18.8%, P=0.0016). In the IVM group, there were no differences in development time points between implanted and non-implanted embryos. IVM zygotes showed increased abnormal cleavage compared with IVF; however, there were no significant differences in pregnancy rate or abortion rate between IVM and IVF. We rejected these abnormal cleaved embryos for transfer, indicating that in order to improve the pregnancy rate it is important to exclude the abnormal cleaved embryo, such as direct cleavage, from embryo transfer in IVM treatment.

IVM in need of clear definitions.

Oocyte in vitro maturation (IVM) involves the achievement of the process of oocyte maturation in vitro Clinically, it was introduced several decades ago as a potentially more patient-friendly and less expensive assisted reproductive technology (ART) approach, as immature oocytes collected from mid-antral follicles can be matured in vitro without prior gonadotrophin stimulation. However, IVM oocytes are developmentally less competent compared with oocytes matured in vivo, a fact that has encouraged the use of short FSH priming and/or hCG triggering in IVM cycles. These alternatives have generated much confusion about the definition and clinical outcome of IVM, also among ART specialists, especially because hCG triggering can support maturation in vivo even in follicles of 10-13 mm in diameter. In a recent manuscript, a team of IVM specialists propose that IVM should include any ART approach involving 'the collection of oocyte from small and intermediate sized follicles' even after hCG or GnRH triggering. It is more than predictable that other scientists and clinicians with an interest in IVM will object to such a definition, believing that semantically and operatively IVM should not be associated with pharmacological interventions aimed at promoting or achieving maturation in vivo, although partially.

Clinical definition paper on in vitro maturation of human oocytes.

In vitro maturation (IVM) of human oocytes is a reproductive technique which has been practiced for 25 years and is gaining popularity. However, the techniques used for IVM differ substantially across clinics and they result in extremely variable pregnancy rates, partially due to some of these differences in protocols. Such differences include the use in some cycles of hCG triggering prior to oocyte retrieval and the use of a few days of gonadotrophin treatment to support moderate follicle growth. Other important factors are patient selection (including those with polycystic ovaries or decreased ovarian reserve), the number of embryos transferred and cleavage-stage embryo or blastocyst transfer. There are also substantial differences of opinion among clinicians regarding IVM and what it implies. Due to the large variation in protocols, a decision was made to write this paper in an attempt to introduce uniformity when comparing treatments and outcomes of IVM. A clinical definition of IVM was developed: The retrieval of oocytes from small and intermediate sized follicles in an ovary before the largest follicle has surpassed 13 mm in mean diameter. The use of short gonadotrophin stimulation should be acknowledged. However, it should be stated that metaphase II oocytes also have the potential to be collected at that time in the cycles associated with either hCG or GnRH agonist priming. Many feel this is not IVM because some mature oocytes are retrieved, therefore, we recommend renaming this procedure either natural cycle IVF or modified natural cycle IVF (if gonadotrophin stimulation is given) with early triggering, combined with IVM The percentage as well as the absolute number of mature oocytes at retrieval should be indicated. The use of these titles will allow transparency when comparing results of IVM cycles.

Application of serum anti-Müllerian hormone levels in selecting patients with polycystic ovary syndrome for in vitro maturation treatment

ObjectiveThe purpose of this study was to identify useful clinical factors for the identification of patients with polycystic ovary syndrome (PCOS) who would benefit from in vitro maturation (IVM) treatment without exhibiting compromised pregnancy outcomes.MethodsA retrospective cohort study was performed of 186 consecutive patients with PCOS who underwent human chorionic gonadotropin-primed IVM treatment between March 2010 and March 2014. Only the first IVM cycle of each patient was included in this study. A retrospective case-control study was subsequently conducted to compare pregnancy outcomes between IVM and conventional in vitro fertilization (IVF) cycles.ResultsThrough logistic regression analyses, we arrived at the novel finding that serum anti-Müllerian hormone (AMH) levels and the number of fertilized oocytes in IVM were independent predictive factors for live birth with unstandardized coefficients of 0.078 (95% confidence interval [CI], 1.005–1.164; p=0.037) and 0.113 (95% CI, 1.038–1.208; p=0.003), respectively. Furthermore, these two parameters were able to discriminate patients who experienced live births from non-pregnant IVM patients using cut-off levels of 8.5 ng/mL and five fertilized oocytes, respectively. A subsequent retrospective case-control study of patients with PCOS who had serum AMH levels ≥8.5 ng/mL showed that IVM had pregnancy outcomes comparable to conventional IVF, and that no cases of ovarian hyperstimulation syndrome were observed.ConclusionSerum AMH levels are a useful factor for predicting pregnancy outcomes in PCOS patients before the beginning of an IVM cycle. IVM may be an alternative to conventional IVF for PCOS patients if the patients are properly selected according to predictive factors such as serum AMH levels.

Morphokinetics of embryos developed from oocytes matured in vitro

In in vitro maturation (IVM) cycles primed with human chorionic gonadotropin (hCG), both immature and mature oocytes are retrieved from antral follicles sized 8-12mm. Using time-lapse microscopy, we compared the morphokinetic behavior of embryos developed from oocytes matured in vivo and in vitro, testing the hypothesis that IVM affects preimplantation development. Furthermore, we extended the morphokinetic analysis of these embryos by a comparison with embryos obtained in stimulated assisted reproduction technology (ART) cycles. In IVM cycles primed with follicle-stimulating hormone (FSH)/hCG, prior to sperm microinjection, oocytes surrounded by an expanded cumulus at retrieval and presumably mature (EC-MII) were incubated for 6h, while immature oocytes enclosed in a compact cumulus (CC) were matured in vitro for 30h. The morphokinetics of embryos selected for transfer or cryopreservation, derived from EC-MII and CC oocytes, were comparatively and retrospectively analyzed in terms of cleavage times (t2, t3, t4, t5, and t8) and intervals (cc2, cc3, s2, s3). For further comparison, the morphokinetics of embryos selected for transfer or cryopreservation (ICSI) or giving rise to ongoing pregnancies (model) in stimulated ART cycles was also assessed. The morphokinetic behavior of EC-MII and CC embryos was entirely comparable, as suggested by the absence of statistical differences in the averages of all cleavage times and intervals. Almost all cleavage and interval times were also similar between EC-MII, CC, ICSI, and model groups, with the exception of t4 and s2, which were delayed and longer, respectively, in embryos generated in IVM cycles (EC-MII and CC). These findings do not support the hypothesis that maturation in vitro affects embryo morphokinetics, while they suggest only marginal differences in the morphokinetics of embryos developed from oocytes matured in vivo and in vitro in IVM cycles and embryos developed from mature oocytes recovered in stimulated cycles.

Double-strand DNA breaks and repair response in human immature oocytes and their relevance to meiotic resumption.

Only 50-60 % of immature human oocytes attain the mature stage in vitro. Such a deficiency may be a reflection of inadequate conditions of in vitro maturation (IVM) or a manifestation of intrinsic oocyte defects. In the present study, we explored the possibility that the DNA of immature oocytes may be damaged and that such a condition, or inability to trigger a repair action, is associated to germinal vesicle (GV) arrest. Immature oocytes (GV-stage oocytes) were obtained from women undergoing stimulated (Stim-C) or IVM (IVM-C) cycles. GV oocytes obtained from stimulated cycles were fixed for successive analysis either after recovery (T0) or following 30 h (T30) of culture if still arrested at the GV stage. Oocytes retrieved in IVM cycles were used only if they were found arrested at the GV stage after 30 h (T30) of culture. All oocytes were fixed and stained to detect chromatin and actin. They were also assessed for positivity to γH2AX and Rad51, markers revealing the presence of double-strand DNA breaks and the activation of a DNA repair response, respectively. Labelled oocytes were analysed using a Leica TCS SP2 laser scanning confocal microscope. In Stim-C oocytes, γH2AX positivity was 47.5 and 81.5 % in the T0 and T30 groups, respectively (P = 0.003), while γH2AX-positive oocytes were 58.3 % in the IVM-C T30 group (Stim-C T0 vs. IVM-C T30, P = 0.178; Stim-C T30 vs. IVM-C T30, P = 0.035). Positivity for nuclear staining to Rad51 occurred in 42.1 and 74.1 % of Stim-C in the T0 and T30 subgroups, respectively (T = 0.006), while 66.7 % of IVM-C T30 oocytes resulted positive for a DNA repair response (Stim-C T0 vs. IVM-C T30, P = 0.010; Stim-C T30 vs. IVM-C T30, P = 0.345). The present data document the existence of double-strand DNA breaks (DSBs) in human immature oocytes. Also, they are consistent with the hypothesis that insults to DNA integrity may be an important factor affecting meiotic resumption.

Embryos from in Vitro Maturation (IVM) Technique Can Be Successfully Vitrified Resulting in the Birth of a Healthy Child

IVM can be an advantageous technique when applied to PCOS (Polycystic Ovarian Syndrome) patients. The oocytes are retrieved from antral follicles of non-stimulated ovaries, specially preventing hyperstimulation syndrome. Apart from its role as a reproductive treatment, IVM has emerged as a promising tool for emergency fertility preservation, since it can be performed flexibly in either follicular or luteal phase. A 34-year-old patient with PCOS, high body mass index and tubal factor was submitted twice to IVM treatment. Her husband has low count spermatozoa. The first IVM cycle was in 2009, she transferred 3 fresh embryos and got pregnant giving birth to a healthy boy weighing 3.3 kg. In 2013, the patient returned for another IVM cycle and the embryos had to be vitrified because she failed to develop an adequate endometrium for transfer. In the next cycle, the endometrium was prepared using estrogen and progesterone and the two best embryos were warmed up and transferred. She became pregnant and after 36 weeks gave birth to a healthy girl weighing 2.7 kg. She still has four embryos left to transfer. IVM may be an alternative technique to be considered when dealing with PCOS patients. Although clinical outcomes are currently inferior when compared with conventional hormone driven ART (Artificial Reproductive Techniques), it does apply in some cases while preventing hyperstimulation risks. Thus, embryos obtained by IVM can also be vitrified with successful outcomes.