Assisted Hatching Research Articles

EFFECT OF LASER-ASSISTED HATCHING ON CLINICAL AND NEONATAL OUTCOMES IN PATIENTS UNDERGOING SINGLE VITRIFIED-WARMED BLASTOCYST TRANSFERS

The American Society for Reproductive Medicine recommends minimal use of assisted hatching (AH) procedures for all patients undergoing in vitro fertilization (IVF), due to poor live-birth data and increased risk of multiple pregnancies (1). However, it can still be disputable considering that no comparison was made between various techniques of AH, different stages of embryo, and types of cycle. Thus, there is a clash of viewpoints in term of AH effectiveness. Furthermore, very few follow-up studies of newborns after AH have been reported.

LASER ASSISTED HATCHING OF HUMAN EMBRYOS AT FERTILIZATION CHECK, ON DAY 1 OF CULTURE, ALLOWS FOR CONTINUOUS UNINTERRUPTED TIME-LAPSE INCUBATION OF 5+ DAYS, WHILE PRODUCING HATCHING BLASTOCYSTS AS EXPECTED

Human embryos must fully hatch from the Zona Pellucida (ZP) for implantation. Furthermore, studies show that implantation rates increase when the embryo has low energy expenditure. Extended culture of embryos to the blastocyst stage does not allow the natural process of hatching to occur, thus necessitating assisted hatching (AH) to breach the ZP for optimal embryo development. This AH is generally performed on day 3 of culture, however this necessitates interrupting any continuous culture of embryos during incubation from day 1 to 7, especially during Time-Lapse.

Assisted hatching of vitrified-warmed blastocysts prior to embryo transfer does not improve pregnancy outcomes

ObjectiveThis study aims to determine the impact of assisted hatching (AH) on pregnancy outcomes in vitrified-warmed blastocyst transfers, and evaluate if embryo expansion or morphology influences outcomes.MethodsA retrospective cohort study was performed including vitrified-warmed blastocyst transfers at our clinic between 2013 and 2017. Of the 2165 embryo transfers, 1986 underwent laser AH and 179 were non-assisted hatched (NAH). The primary outcome was live birth. Secondary outcomes included conception, implantation, clinical pregnancy, clinical pregnancy loss, and monozygotic twinning (MZT).ResultsAH and NAH groups had similar rates of conception (38.7% vs 42.1%), implantation (26.2% vs 27.3%), clinical pregnancy (29.1% vs 30.3%), clinical pregnancy loss (24.0% vs 17.8%), live birth (19.9% vs 20.5%), and MZT (2.08% vs 2.86%). Five pairs of dichorionic/diamniotic twins resulted from single embryo transfers. AH of embryos with expansion grades ≤3 was associated with lower rates of conception (32.5% vs 44.3%%, p < 0.05) and clinical pregnancy (24.0% vs 32.8%, p < 0.05).ConclusionAH prior to transfer of vitrified-warmed blastocysts was not associated with improved pregnancy outcomes. The identification of dichorionic/diamniotic twins from single blastocyst transfers challenges the previously held notion that dichorionic/diamniotic MZTs can only occur from division prior to the blastocyst stage. Prospective studies are needed to validate the novel finding of lower rates of conception and clinical pregnancy after AH in embryos with lower expansion grade.

Factors Associated With Subchorionic Hematoma Formation in Pregnancies Achieved Via Assisted Reproductive Technologies

To determine if certain clinical and/or embryologic factors are independently associated with the increased prevalence of subchorionic hematoma (SCH) among pregnancies achieved via in vitro fertilization (IVF) with fresh embryo transfer (ET). Retrospective chart review. In this retrospective study, data were abstracted from 210 autologous oocyte IVF clinical pregnancies that resulted from fresh ET at a single fertility center from January 2012 through December 2016. Clinical and embryology laboratory variables were analyzed as possible factors associated with the presence or absence of SCH in IVF pregnancies via bivariate associations and multivariable logistic regression analyses. Independent variables included prior uterine surgery versus no uterine surgery, peak estradiol, and progesterone levels, day 3 (n = 92) versus day 5 (n = 118) ET, and assisted hatching versus no assisted hatching. Among the day 5 ET subgroup of 118 patients, 117 had data for the variables inner cell mass (ICM) grading and trophectoderm (TE) because one day 5 ET was at the morula stage. We found a significant bivariate association between TE grading and SCH, where cases with TE grade “A” were significantly less likely to have SCH compared with cases with grades “B” or “C.” This significant difference remained when adjusting for the other factors considered in a multivariable logistic regression model for the probability of SCH. The data analyzed here suggest that a less-advanced trophectoderm grade may be a potential factor that is associated with the presence of SCH in pregnancies achieved via IVF.

The prevalence, promotion and pricing of three IVF add-ons on fertility clinic websites

Research questionHow are IVF clinic websites advertising three common IVF add-ons: assisted hatching, time-lapse embryo imaging and preimplantation genetic testing for aneuploidies (PGT-A)? DesignThe Human Fertilisation and Embryology Authority ‘Choose a fertility clinic‘ website service was used to identify IVF clinics and their websites. Assisted hatching, time-lapse embryo imaging and PGT-A were examined to determine which websites advertised them, what price they charged and what claims they made in relation to the add-ons. ResultsEighty-seven eligible clinics were identified, with 72 unique websites; 37 (43%) clinics were part of one of nine groups of IVF clinics, of sizes ranging from two to eight clinics in the UK. Time-lapse imaging (TLI) was the most frequently advertised of the three add-ons (67% of clinics), followed by PGT-A (47%) and assisted hatching (28%). Very few websites stated that the effectiveness of the add-on was in doubt or unclear (four, two and one websites for TLI, PGT-A and assisted hatching, respectively), and none raised the possibility that an add-on might have negative effects. Claims of efficacy were often based on upstream outcomes (e.g. implantation, pregnancy). Some claims that PGT-A and TLI improved live birth rates were found. There was substantial variation in pricing. ConclusionsIVF clinic websites provide valuable information for patients seeking fertility treatment so it is key that the information is accurate and complete. There is a need for transparent information on interventions, including uncertainties and risks, to be made available by IVF clinics to support well-informed treatment decisions. The selected add-ons are widely advertised, and there is wide variation in pricing.

An effective method for trophectoderm biopsy using mechanical blunt dissection: a step-by-step demonstration

To present an effective approach to trophectoderm biopsy for blastocysts of different stages and characteristics by mechanical blunt dissection (MBD). Stepwise demonstration with still pictures and operational video clips to explain tips and tricks for trophectoderm biopsy. (This demonstration was approved by the Reproductive Study Ethics Committee at Shengjing Hospital of China Medical University.) SETTING: Invitro fertilization laboratory. Patients who underwent preimplantation genetic testing. The illustrated techniques of blastocyst trophectoderm biopsy using micromanipulation methods include artificial shrinkage, zona pellucida drilling, injecting media from the drilling, aspiration of trophectoderm cells into the biopsy pipette (outer diameter 27 μm for fully expanded blastocysts and peanut-shaped hatching blastocysts; outer diameter 20 μm for 8-shaped hatching and hatched blastocysts), detachment of the trophectoderm cells by laser pulse combined with MBD (performed using the rims of the biopsy and holding pipettes), and release of the biopsy fragment. Successful biopsy rate and survival after warming. Our biopsy strategy does not involve assisted hatching on day-3 or day-4 embryos, which can leave the embryo undisturbed in culture up to the expanded blastocyst stage. Notably, this approach demonstrates several noteworthy advantages for sampling blastocysts of different stages and characteristics, and it maintains a desirable successful biopsy rate (95.4%, n = 1,872) and survival rate after warming (100%, n = 440). The MBD method may reduce thermal damage because fewer laser pulses are used, compared with the traditional laser-only biopsy techniques. For noncollapsed blastocysts after artificial shrinkage, the strategy of injecting medium from the zona pellucida drilling helps to separate the trophectoderm cells from the zona pellucida, thus facilitating the biopsy procedure. For peanut-shaped hatching blastocysts, this approach could provide better control over the aspiration of trophectoderm cells into the biopsy pipette. Especially if the inner cell mass is herniating from the zona pellucida, the trophectoderm biopsy can be performed away from the inner cell mass to avoid damaging it. In addition, the MBD approach combined with the biopsy pipette (outer diameter 20 μm) can effectively control the target number of trophectoderm cells, thus simplifying the process of obtaining a biopsy from a hatched blastocyst. Our biopsy approach demonstrates several noteworthy advantages. Considering its benefits and the simplicity of its execution, this systematic biopsy method for blastocysts of different stages and characteristic can be widely applied.

ALADDIN study: does assisted hatching of vitrified/warmed blastocysts improve live birth rate? Protocol for a multicentric randomised controlled trial

IntroductionRecent data suggest a higher clinical pregnancy rate performing assisted hatching (AH) on previously cryopreserved embryos but fail to demonstrate significant effects on live birth rate. However, current evidence is...

Multicenter prospective study of concordance between embryonic cell-free DNA and trophectoderm biopsies from 1301 human blastocysts

The recent identification of embryonic cell-free DNA in spent blastocyst media has opened a new era of possibilities for noninvasive embryo aneuploidy testing in assisted reproductive technologies. Yet, previous studies assessing a limited number of embryos reported variable concordance between embryonic cell-free DNA and trophectoderm biopsies, thus questioning the validity of this approach. This study aimed to evaluate the concordance and reproducibility of testing embryonic cell-free DNA vs trophectoderm DNA obtained from the same embryo in a large sample of human blastocysts and to assess the contribution of the inner cell mass and trophectoderm to embryonic cell-free DNA released to the culture media. This is an interim analysis of a prospective, observational study among 8 invitro fertilization centers in 4 continents to assess consistency between noninvasive embryo aneuploidy testing of embryonic cell-free DNA and conventional trophectoderm biopsy. The analysis included 1301 day-6/7 blastocysts obtained in 406 invitro fertilization cycles from 371 patients aged 20-44 years undergoing preimplantation genetic testing for aneuploidy. Fresh oocytes underwent intracytoplasmic sperm injection or invitro fertilization. No previous assisted hatching or vitrification was allowed before media collection. Individual spent blastocyst medium was collected from embryos cultured at least 40 hours from day 4. After media collection, conventional preimplantation genetic testing for aneuploidy, comprising trophectoderm biopsy and blastocyst vitrification, was performed. Embryonic cell-free DNA was analyzed blindly after embryo transfer. Inner cell mass and trophectoderm biopsies were also performed in a subset of 81 aneuploid blastocysts donated for research. Embryonic cell-free DNA analyses were 78.2% (866/1108) concordant with the corresponding trophectoderm biopsies. No significant differences were detected among centers ranging from 72.5% to 86.3%. Concordance rates exceeded 86% when all defined steps in the culture laboratory were controlled to minimize the impact of maternal and operator contamination. Sensitivity per center ranged from 76.5% to 91.3% and specificity from 64.7% to 93.3%. The false-negative rate was 8.3% (92/1108), and false-positive rate was 12.4% (137/1108). The 2 fertilization techniques provided similar sensitivity (80.9% vs 87.9%) and specificity (78.6% vs 69.9%). Multivariate analysis did not reveal any bias from patient clinical background, ovarian stimulation protocols, culture conditions, or embryo quality on testing accuracy of concordance. Moreover, concordances of embryonic cell-free DNA with trophectoderm and inner cell mass suggest that the embryonic cell-free DNA originates from both compartments of the human embryo. Noninvasive analysis of embryonic cell-free DNA in spent blastocyst culture media demonstrates high concordance with trophectoderm biopsy results in this large multicenter series. A noninvasive approach for prioritizing embryo euploidy offers important advantages such as avoiding invasive embryo biopsy and decreased cost, potentially increasing accessibility for a wider patient population.

Factors associated with subchorionic hematoma formation in pregnancies achieved via assisted reproductive technologies

PurposeTo determine if certain clinical and/or embryologic factors are independently associated with the increased prevalence of subchorionic hematoma (SCH) among pregnancies achieved via in vitro fertilization (IVF) with fresh embryo transfer (ET).DesignRetrospective chart review.MethodsIn this retrospective study, data were abstracted from 210 autologous oocyte IVF clinical pregnancies that resulted from fresh ET at a single fertility center from January 2012 through December 2016. Clinical and embryology laboratory variables were analyzed as possible factors associated with the presence or absence of SCH in IVF pregnancies via bivariate associations and multivariable logistic regression analyses. Independent variables included prior uterine surgery versus no uterine surgery, peak estradiol, and progesterone levels, day 3 (n = 92) versus day 5 (n = 118) ET, and assisted hatching versus no assisted hatching. Among the day 5 ET subgroup of 118 patients, 117 had data for the variables inner cell mass (ICM) grading and trophectoderm (TE) because one day 5 ET was at the morula stage.ResultsWe found a significant bivariate association between TE grading and SCH, where cases with TE grade “A” were significantly less likely to have SCH compared with cases with grades “B” or “C.” This significant difference remained when adjusting for the other factors considered in a multivariable logistic regression model for the probability of SCH.ConclusionsThe data analyzed here suggest that a less-advanced trophectoderm grade may be a potential factor that is associated with the presence of SCH in pregnancies achieved via IVF.

Higher implantation and live birth rates with laser zona pellucida breaching than thinning in single frozen-thawed blastocyst transfer

While zona pellucida (ZP) breaching of day-3 frozen blastocysts embryos can increase the blastocyst hatching rate, compared with ZP thinning, the pregnancy and implantation rates are similar. The aim of this study was to compare pregnancy outcomes and the risks associated with frozen-thawed blastocysts between laser ZP breaching and laser ZP thinning. For the thinning group, ZP of thawed blastocyst was thinned to a length of 30-40μm using laser between January 2013 and October 2015. On the other hand, for the breaching group, thawed blastocysts were breached with a 60-80μm hole in the ZP using laser between November 2015 and April 2018. The implantation rate of ZP breaching (72.7%) was higher than that of ZP thinning (61.8%). In single frozen blastocyst transfer, the implantation rate, clinical pregnancy rate, and live birth rate of ZP breaching (73.9%, 73.9%, 61.8%, respectively) were significantly higher than those of ZP thinning (60.9%, 60.9%, 46.7%, respectively). The abortion rate, preterm birth rate, congenital malformation, birth defects, and birth weight did not significantly differ between the two groups. In conclusion, laser assisted hatching during single frozen blastocyst transfer using ZP breaching exhibit higher implantation, pregnancy, and live birth rates compared with ZP thinning. No significant differences were observed between the two assisted hatching methods in terms of adverse effects on pregnancy and newborns.

Which is the safer method for trophectoderm biopsy in mouse blastocyst, mechanical or laser?

Introduction: This study was conducted to compare hatching rates after assisted hatching, re-expansion rates after trophectoderm biopsy, and survival rates after cryopreservation using different methods of assisted hatching and biopsy in mouse embryo. Materials and Methods: Five-week-old female mice (C57BL/CBA) were superovulated, and two-cell embryos were collected. All embryos were cultured to blastocyst stage. For assisted hatching and separating trophectoderm from blastocyst, laser device and hand-made pipette were used respectively. Hatching rates after assisted hatching, re-expansion rates after trophectoderm biopsy, and survival rates after cryopreservation were calculated. Results: Hatching rate was 92% in mechanically assisted hatching group and 90% in laser group, respectively. After mechanically assisted hatching, re-expansion rate was 91.3% and survival rate was 87% in biopsy by pipette and laser group, respectively. In laser hatching group, re-expansion rate was 88.9% with biopsy by pipette and survival rate was 84.4% with biopsy by laser. Conclusion: Throughout the study, mechanical technique and laser technique showed no differences in the safety profiles in trophectoderm biopsy procedure.

Factors associated with embryo splitting and clinical outcome of monozygotic twins in pregnancies after IVF and ICSI.

What factors are associated with monozygotic twins (MZT) after autologous IVF/ICSI with fresh and frozen/thawed single embryo transfer (SET) and what is the outcome of MZT?Factors associated with increased MZT were blastocyst transfer and elective single embryo transfer (eSET), with MZT showing a lower gestational age at birth and neonatal weight but higher perinatal mortality only after fresh transfer.ART is associated with an increased incidence of MZT, which carries higher perinatal mortality. However, risk factors associated with MZT are still controversial.A population-based retrospective analysis of data extracted from ART cycles reported to the Latin American Registry of ART between January 2012 and December 2016 was used in order to study the frequency and outcome of MZT after SET.In total, 2925 clinical pregnancies obtained after autologous IVF/ICSI with fresh SET were used to study biomedical factors possibly associated with MZT, such as maternal age, type of insemination, use of assisted hatching, stage of embryo development at transfer, elective or non-elective SET and preimplantation genetic testing. Another group of 3085 clinical pregnancies obtained after SET of frozen-thawed embryo transfer (FET) was also used to study the possible association between embryo freezing and MZT. Only pregnancies with complete follow-up until birth were included in this analysis. The diagnosis of MZT was established by transvaginal ultrasound performed at 6–8 weeks of amenorrhea. The rate of MZT for each potential risk factor was obtained and a multivariable logistic regression was performed in order to account for the above-mentioned factors. Pregnancies were followed until birth and the early neonatal period in order to assess the rate of miscarriage and stillbirths, gestational age at birth, neonatal weight and early neonatal mortality.There were 76 MZT out of 2925 clinical pregnancies with fresh SET (2.6%) and 69 MZT out of 3085 clinical pregnancies after FET (2.2%) (odds ratio (OR) = 0.85, 95% CI 0.61–1.19). A statistically significantly increase in MZT rate was observed with blastocyst compared with cleavage stage ET (3.4 versus 2.0%, respectively; OR = 1.70, 95% CI 1.05–2.76). When confounding variables were considered, eSET was also significantly associated with an increase in the odds of MZT (OR = 1.74, 95% CI 1.04–2.92). Overall perinatal mortality was higher in MZT compared with singletons, but this rise was only significant after fresh ET.Limitations of the current study result from the fact that MZT were diagnosed with ultrasound performed at 6–8 weeks of amenorrhea; therefore, spontaneous embryo reductions taking place earlier were missed.Reproductive health providers must inform their patients that blastocyst transfer and eSET of fresh embryos are associated with a statistically significantly increase in the odds of MZT and that perinatal mortality after fresh ET is significantly higher in MZT than in singletons.The Latin American Registry of ART receives direct funding from Ferring Pharmaceuticals, but no specific funding was received to undertake this study. None of the authors declare conflict of interest.

Analysis of 122 triplet and one quadruplet pregnancies after single embryo transfer in Japan.

What is the prevalence of triplet and quadruplet pregnancies after single embryo transfer (SET) in Japan. A retrospective observational study was conducted on 274,605 pregnancies after 937,848 SET cycles in registered assisted reproductive technology (ART) data from the Japanese ART national registry database between 2007 and 2014. A questionnaire survey of ART centres was also conducted. Data on pregnancies with embryo division into three or more after SET were analysed. According to the Japanese ART national registry database, SET resulted in 109 triplet pregnancies (0.04% of pregnancies), and the questionnaire reports from 31 centres revealed 33 triplet and one quadruplet pregnancies. After exclusion of 20 duplicated cases, 122 triplet and one quadruplet pregnancies included 46 monochorionic (one gestational sac [37.4%]), 18 dichorionic (two gestational sacs [14.6%]) and 59 trichorionic pregnancies (three gestational sacs [48.0%]). Compared with singleton pregnancies, patients with monozygotic triplet or quadruplet pregnancies were less frequently diagnosed with unexplained infertility (P = 0.004), more often received gonadotrophin injections for ovarian stimulation in 39 cases with information available (P = 0.021) and underwent more blastocyst transfers and assisted hatching (P = 0.002 and P < 0.001, respectively). The proportion of live birth, defined as at least one baby born, excluding induced abortion, was 64.6% (73/116 pregnancies) of monozygotic triplet or quadruplet pregnancies. Combined Japanese ART national registry and survey data revealed 122 triplet and one quadruplet pregnancies, the majority after cryopreserved embryo transfer. Most were conceived after blastocyst transfer and often after assisted hatching, which are potential risk factors for zygotic splitting.

Does assisted hatching affect live birth in fresh, first cycle in vitro fertilization in good and poor prognosis patients?

To assess the effect of assisted hatching (AH) on live birth rate (LBR) in first cycle, fresh in vitro fertilization (IVF) in good and poor prognosis patients. Retrospective cohort using cycles reported to the Society for Assisted Reproductive Technology Clinic Outcomes Reporting System. Live birth rate was compared in women who underwent first cycle, autologous, fresh IVF cycles with (n = 48,858) and without (n = 103,413) AH from 2007 to 2015. The propensity-weighted LBR was 39.2% with AH versus 43.9% without AH in all patients. The rate difference (RD) with AH was - 4.7% ([CI - 0.053, - 0.040], P < 0.001) with the calculated number needed to harm being 22. AH affected live birth in both good prognosis and poor prognosis patients. The propensity-weighted monozygotic twinning (MZT) rate was 2.3% in patients treated with AH as compared to 1.2% patients that did not receive AH. The RD with AH on MZT in fresh, first IVF cycles was 1.1% ([0.008, 0.014], P < 0.001). AH may affect LBR across all patients and in poor prognosis patients in fresh IVF cycles. Caution should be exercised when applying this technology. More prospective research is needed.

Day 2 laser assisted hatching (AH) significantly improves implantation rates in fresh blastocyst transfers

The efficacy of assisted hatching has been widely debated. The variable results reported for AH are confounded by the numerous methods of performing AH, including mechanical partial zona dissection, acid tyrode’s, and more recently by laser assistance. Assisted hatching has most commonly been performed on Day 3 embryos. This study assesses if Day 2 laser assisted hatching can improve implantation rates for fresh blastocyst transfers. Prospective observational cohort. On the morning of Day 2 of culture, all embryos were sorted into groups (<4-cell, 4-cell and >4-cells). Those in the AH group underwent laser assisted hatching using an Octax laser (4.0ms) on the morning of Day 2 at the time of embryo check. All embryos were then cultured undisturbed until assessment on the morning of Day 5 when the highest quality embryo(s), based on morphology, were selected for embryo transfer. A total of 446 fresh Day 5 transfers between Jan 2016 - Mar 2019 were analyzed (244 transfers with AH and 202 transfers without AH). A total of 682 embryos were transferred in the 446 cycles (363 embryos in the AH group and 319 embryos in the non-AH group). Because 206 of the 446 transfers involved transfer of more than 1 embryo, a mixed model accounting for both fixed and random effects (i.e. repeated measurements) was used, with SAC modeled as a function of the fixed effects assisted hatching (AH), age, and body mass index (BMI). Day 2 assisted hatching is associated with successful implantation (p=0.036). As expected, age was negatively associated with implantation rate (p<0.0001). BMI was not. The R-square for the model was 0.52, and the variance component of the random effects (owing to multiple embryo transfers) was 0.082 (95% CI [0.046-0.11]).Tabled 1No AHWith AHTotal# Fresh Day 5 Transfers202244446Mean Maternal Age35.634.435.0Mean BMI26.827.026.9Mean # Embryos Transferred1.581.491.53# Embryos319363682# Sacs137194331Implantation Rate (%)42.9%53.4%48.5% Open table in a new tab Large data sets such as the SART database do not allow for evaluation of the impact of specific AH techniques. Certainly, any embryo handling and exposure has the potential to be detrimental to blastocyst development and implantation rates. Here, we show that Day 2 laser AH can lead to a significant increase in implantation rates from 42.9% without AH to 53.4% with AH. Day 2 embryos generally have larger perivitelline space which may allow for reduced peripheral laser exposure to the blastomeres. Further studies are needed to confirm if Day 2 laser AH confers benefit over Day 3 laser AH.

Prevalence, risk factors and obstetric outcomes of zygotic splitting after single embryo transfer cycles

To describe the prevalence, main determining factors and obstetric outcomes of multiple pregnancy due to zygotic splitting after single embryo transfer (sET). We performed a retrospective observational study in 521 clinical pregnancies resulting from cleavage-stage or blastocyst single embryo transfer (sET) following IVF or ICSI cycles with autologous or donated eggs. Fresh and frozen-warmed sET from January 2015 to June 2017 were included, and analyzed for the occurrence of assisted hatching, embryo biopsy for PGT, or insemination type (IVF vs. ICSI). We also evaluated embryo grading, blastocyst expansion grade, and quality of embryo transfer. We retrospectively analysed all pregnancies achieved through single embryo transfers at our center. The population included IVF or ICSI cycles with autologous or donated eggs, and/or their subsequent frozen-thawed cycle. Monozygotic twinning was defined as 2 or more heart beats at 5-6 weeks ultrasound. We analyzed 521 clinical pregnancies resulting from 1708 single embryo transfers in cleavage-stage (N=674) or blastocyst stage (N=1034). The overall MZT rate 2.87% (15/521), accounting for 0.87 % of cleavage stage derived pregnancies (1/115) and 3.45% of blastocyst stage derived pregnancies (14/406, p=0.01). The incidence of MZT was higher with ICSI (14/368) compared to conventional IVF (1/153), although not statistically significant (P=0,08). In the blastocyst transfer group the incidence of MZT was not increased by Assisted Hatching (AH), Preimplantation Genetic Testing (PGT) nor was it affected by type of transfer, (either fresh or frozen) or quality/type of catheter used in the transfer. Fifteen patients with MZT had 10 term deliveries with no neonatal complications, four of which had vanishing embryos, (one of them triple with a double vanishing embryo). One case had placenta accreta and underwent cesarean hysterectomy. Four patients miscarried, 2 in the first trimester and two in the second trimester ( one due to cervical incompetence, and one voluntary interruption, due to a thoracopagus Siamese Twin pregnancy) Finally, one patient delivered at 30 weeks, with twin neonatal demise. Although MZT is a rare event associated with ART it cannot be disregarded due to its potentially serious obstetric consequences, especially in a sET blastocyst transfer program. Monozygotic twinning is increased in blastocyst transfers, and special care should be taken to properly inform prospective parents when blastocysts are transferred.

The Effect of Assisted Hatching on Live Birth Rate Following Fresh Embryo Transfer in Advanced Maternal Age

Assisted hatching (AH) was introduced 3 decades ago as an adjunct method to in vitro fertilization (IVF) and embryo transfer (ET) to improve embryo implantation rate. Limited data are available on the effect of AH on live birth rate (LBR) in advanced maternal age. The objective of this study is to investigate the effect of AH on LBR in women aged 40 years and older. A retrospective study conducted at a single academic reproductive center. Women aged ≥40 years, who were undergoing their first IVF cycle were included. Laser-assisted hatching was the method used for AH and single or double embryos were transferred. Embryo transfer was performed at the cleavage or blastocyst stage. Separate analysis was performed on each ET stage. Live birth rate was the primary outcome. A total of 892 patients were included. Of these, 681 women underwent cleavage ET and 211 underwent blastocyst ET. The clinical pregnancy rate in the entire group was 15.3% and the LBR was 10.2%. Baseline and cycle parameters between the AH group and the control group were comparable. Assisted hatching in the cleavage stage was associated with lower clinical pregnancy rate (odds ratio [OR], 0.52; confidence interval [CI], 0.31-0.86; P = .012) and lower LBR (OR, 0.36; CI, 0.19-0.68; P = .001). Assisted hatching did not have any effect on outcomes in blastocyst ET. Assisted hatching does not improve the reproductive outcomes in advanced maternal age. Performing routine AH for the sole indication of advanced maternal age is not clinically justified.

Effect of Total versus Partial Assisted Hatching on the Clinical Pregnancy Rates in Assisted Reproduction Technology

Objective: The objective of this study was to investigate the effect of total or partial assisted hatching on the clinical pregnancy rates in assisted reproduction technology.Study Design: This was a case-control study conducted from the beginning of January 2016 to the end of June 2017. A total of 404 cycles were included in this case-control study. Study population was divided into 3 groups: Group 1: Partial assisted hatching (n=118), Group 2: Total assisted hatching (n=81) and Control group (n=205).Results: In women of all ages, clinical pregnancy rates were similar between groups with total or partial assisted hatching compared to control group (p&gt;0.05). The rates were also similar in subgroups of women with blastocyst or cleavage stage embryo transfers (p&gt;0.05). Partial or total embryo hatching did not result in favorable outcome compared to control group either in women over 35 or younger than 35 years of age (p&gt;0.05). In whole study group pregnancy rate was significantly higher in group with blastocyst stage embryo transfers (22.4 % versus 48.8%, p&lt;0.05)Conclusion: Partial or total assisted hatching do not have any impact on the clinical pregnancy rates, no significant impact was determined in subgroup of women either.

Risk factors for monozygotic twinning after in vitro fertilization: a systematic review and meta-analysis

To establish the risk factors for monozygotic twin (MZT) and monochorionic twin (MCT) pregnancies after invitro fertilization (IVF). Systematic review and meta-analysis. Not applicable. Women who achieved MZT and non-MZT pregnancies through IVF. Systematic search of Medline from January 1995 to October 2018 with cross-checking of references from relevant articles in English. Possible risk factors for MZT or MCT pregnancies after IVF, comprising extended embryo culture, insemination method (conventional IVF and intracytoplasmic sperm injection [ICSI]), embryo biopsy for preimplantation genetic testing for aneuploidies or for monogenic/single-gene defects (PGT-A or PGT-M) programs, assisted hatching (AH), oocytes donation, female age, and embryo cryopreservation. A total of 40 studies were included. Blastocyst transfer compared with cleavage-stage embryo transfer, and female age <35years were associated with a statistically significant increase in the MZT and MCT pregnancy rate after IVF: (23 studies, OR 2.16, 95% CI, 1.74-2.68, I2=78%; 4 studies, OR 1.29; 95% CI, 1.03-1.62, I2=62%; and 3 studies, OR 1.90, 95% CI, 1.21-2.98, I2=59%; 2 studies, OR 2.34; 95% CI, 1.69-3.23, I2=0, respectively). Conventional IVF compared with ICSI and assisted hatching were associated with a statistically significantly increased risk of MZT pregnancy (9 studies, OR 1.19, 95% CI, 1.04-1.35, I2=0; 16 studies, OR 1.17, 95% CI, 1.09-1.27, I2=29%, respectively). Embryo biopsy for PGT-A or PGT-M, embryo cryopreservation, and oocytes donation were not associated with MZT pregnancies after IVF. Blastocyst transfer is associated with an increased risk of both MZT and MCT pregnancies after IVF. Further evidence is needed to clarify the impact of female age, insemination method and AH on the investigated outcomes.

Laser-assisted hatching and clinical outcomes in frozen-thawed cleavage-embryo transfers of patients with previous repeated failure.

Assisted hatching (AH) is initially developed to provide an artificial manipulation of the zona pellucida (ZP) to help embryos hatch and improve the capacity of the embryos to implant. However, these effects remain unclear and controversial because of variation in patient characteristics, and it is critical to ascertain the indications for AH and to identify those patients who might benefit from AH. Here, this study aimed to assess the effect of laser-assisted zona thinning hatching technology (LAH) during the frozen-thawed D3 embryos on pregnancy outcomes in patients with previous repeated failures in vitro fertilization-embryo transfer (IVF-ET). To the best of our knowledge, these relationships have not been previously investigated. A retrospective cohort analysis was carried out. Infertility patients with previous repeated failure who underwent assisted reproductive therapy at our in vitro fertilization (IVF) center from May 2014 to May 2016 were enrolled. A total of 415 cleavage FET cycles (225 in the LAH group and 190 in the control group) were analyzed. Clinical outcomes including clinical pregnancy, implantation, live birth, miscarriage, and multiple gestation rates after transfer were compared between the LAH and control groups. The clinical pregnancy (49.3% versus 38.9%) and implantation rates (31.2% versus 24.6%) were significantly higher for the LAH group than the control group (P < 0.05). The live birth (44.8% versus 35.8%), multiple pregnancy (32.4% versus 31.0%), preterm birth (22.8% versus 17.1%), miscarriage (7.2% versus 5.4%), and ectopic rates (1.9% versus 0%) did not differ significantly between the two groups (P > 0.05). This study showed that LAH via zona pellucida (ZP) thinning significantly improves clinical outcomes, particularly clinical pregnancy and implantation rates, associated with FET cycles among patients with previous repeated failure.