Effect of various contraceptives on oocyte yield and maturation in patients undergoing planned oocyte cryopreservation.

RESEARCH QUESTION: Do the various forms of hormonal and non-hormonal contraceptives have any association with ovarian stimulation outcomes, such as oocyte yield and maturation, in patients undergoing planned oocyte cryopreservation (POC)? DESIGN: This retrospective cohort study included all patients who underwent POC cycles between 2011 and 2023. The use of types of contraception before a POC cycle was recorded. The study evaluated the median number of cumulus-oocyte complexes obtained after vaginal oocyte retrieval and the proportion of metaphase II oocytes that underwent vitrification among all the cohorts. RESULTS: A total of 4059 oocyte freezing cycles were included in the analysis. Eight types of contraceptive method were recognized in patients undergoing ovarian stimulation: intrauterine device (IUD), copper (n = 84); IUD, levonorgestrel low dose (<52 mg) (n = 37); IUD, levonorgestrel (n = 192); subdermal etonogestrel implant (n = 14); injectable medroxyprogesterone acetate (n = 11); etonogestrel vaginal ring (n = 142); combined oral contraceptive pills (n = 2349); and norelgestromin transdermal patch (n = 10). The control group included patients not using contraceptives or using barrier or calendar methods (n = 1220). Among all the cohorts the median number of cumulus-oocyte complexes retrieved during oocyte retrieval was comparable (P = 0.054), and a significant difference in oocyte maturity rate with median number of vitrified oocytes was found (P = 0.03, P < 0.001, respectively). After adjusting for confounders a multivariate analysis found no association between the type of contraceptive and proportion of metaphase II oocytes available for cryopreservation. CONCLUSIONS: Among the various forms of contraception, none was shown to have an adverse association with oocyte yield or maturation rate in patients undergoing POC.

Assessing the clinical viability of micro 3 pronuclei zygotes.

PURPOSE: What is the rate of euploidy and clinical viability of embryos resulting from micro 3 pronuclei zygotes? METHODS: Retrospective cohort analysis in a single, academic in vitro fertilization (IVF) center from March 2018 to June 2021. Cohorts were separated by fertilization as either a 2 pronuclear zygote (2PN) or micro 3 pronuclear zygote (micro 3PN). PGT-A was performed to identify embryonic ploidy rates in embryos created from micro 3PN zygotes. The clinical outcomes of all transferred euploid micro 3PN zygotes were evaluated from frozen embryo transfer (FET) cycles. RESULTS: During the designated study period, 75,903 mature oocytes were retrieved and underwent ICSI. Of these, 60,161 were fertilized as 2PN zygotes (79.3%) and 183 fertilized as micro 3PN zygotes (0.24%). Of the micro 3PN-derived embryos that underwent biopsy, 27.5% (n=11/42) were deemed euploid by PGT-A, compared to 51.4% (n=12,301/23,923) of 2PN-derived embryos, p=0.06. Four micro 3PN-derived embryos were transferred in subsequent single euploid FET cycles, which includes one live birth and one ongoing pregnancy. CONCLUSION: Micro 3PN zygotes that develop to the blastocyst stage and meet the criteria for embryo biopsy have the potential to be euploid by preimplantation genetic testing for aneuploidy (PGT-A) and if selected for transfer can achieve a live birth. Although there are a significantly lower number of micro 3PN embryos that make it to blastocyst biopsy, the potential to continue to culture abnormally fertilized oocytes may give these patients a chance at pregnancy that they previously did not have.

Clinical implementation of algorithm-based embryo selection is associated with improved pregnancy outcomes in single vitrified warmed euploid embryo transfers.

PURPOSE: To assess whether utilization of a mathematical ranking algorithm for assistance with embryo selection improves clinical outcomes compared with traditional embryo selection via morphologic grading in single vitrified warmed euploid embryo transfers (euploid SETs). METHODS: A retrospective cohort study in a single, academic center from September 2016 to February 2020 was performed. A total of 4320 euploid SETs met inclusion criteria and were included in the study. Controls included all euploid SETs in which embryo selection was performed by a senior embryologist based on modified Gardner grading (traditional approach). Cases included euploid SETs in which embryo selection was performed using an automated algorithm-based approach (algorithm-based approach). Our primary outcome was implantation rate. Secondary outcomes included ongoing pregnancy/live birth rate and clinical loss rate. RESULTS: The implantation rate and ongoing pregnancy/live birth rate were significantly higher when using the algorithm-based approach compared with the traditional approach (65.3% vs 57.8%, p<0.0001 and 54.7% vs 48.1%, p=0.0001, respectively). After adjusting for potential confounding variables, utilization of the algorithm remained significantly associated with improved odds of implantation (aOR 1.51, 95% CI 1.04, 2.18, p=0.03) ongoing pregnancy/live birth (aOR 1.99, 95% CI 1.38, 2.86, p=0.0002), and decreased odds of clinical loss (aOR 0.42, 95% CI 0.21, 0.84, p=0.01). CONCLUSIONS: Clinical implementation of an automated mathematical algorithm for embryo ranking and selection is significantly associated with improved implantation and ongoing pregnancy/live birth as compared with traditional embryo selection in euploid SETs.

What is the reproductive potential of day 7 euploid embryos?

STUDY QUESTION: What is the rate of euploidy and the reproductive potential of embryos biopsied after 6 days of development? SUMMARY ANSWER: Embryos biopsied after 6 days of development have higher rates of aneuploidy; however, day 7 euploid embryos selected at transfer can achieve acceptable pregnancy rates and live birth (LB) outcomes. WHAT IS KNOWN ALREADY: Recent publications have shown promising treatment results after euploid day 7 embryo transfers (ETs), albeit these studies were limited by small sample sizes. Whereas the current clinical standard has been to discard embryos that do not reach expansion by day 6 of development, the lack of robust data surrounding the clinical utility of day 7 embryos warrants further evaluation. STUDY DESIGN, SIZE, DURATION: Retrospective cohort analysis in a single, academic in vitro fertilization (IVF) center from January 2012 to March 2018. A total of 25 775 embryos underwent trophectoderm (TE) biopsy and preimplantation genetic testing for aneuploidy (PGT-A). Additionally, the clinical IVF outcomes of 3824 single, euploid frozen embryo transfer (FET) cycles were evaluated. PARTICIPANTS/MATERIALS, SETTING, METHODS: Cohorts were segregated by day of TE biopsy following oocyte retrieval (day 5, day 6 or day 7). PGT-A was performed to identify embryonic ploidy rates. Secondly, IVF and LB outcomes after single, euploid FET were evaluated for each cohort. MAIN RESULTS AND THE ROLE OF CHANCE: A total of day 5 (n = 12 535), day 6 (n = 11 939) and day 7 (n = 1298) embryos were included in the study analysis. The rate of embryo euploidy was significantly lower in day 7 blastocysts compared to day 5 or day 6 cohorts (day 7 = 40.5%; day 5 = 54.7%; day 6 = 52.9%; (P < 0.0001)). After adjusting for age, anti-Müllerian hormone, BMI, embryo quality and number of embryos biopsied, there was a significant association between aneuploidy and embryos biopsied on day 7 when compared to day 5 biopsied embryos (OR = 1.34, CI 95% 1.09-1.45, P = 0.001) and day 6 biopsied embryos (OR = 1.26, CI95% 1.07-1.16, P < 0.001).A sub-analysis of subsequent 3824 single, euploid FET cycles (day 5: n = 2321 cycles; day 6: n = 1381 cycles; and day 7: n = 116 cycles) showed significant differences among cohorts in implantation, clinical pregnancy, LB and clinical loss rates. There was a significant decrease in the odds of implantation, clinical pregnancy and LB, but no association with clinical loss or multiple pregnancy rates in patients who utilized day 7-biopsied embryos during treatment. LIMITATIONS, REASONS FOR CAUTION: The retrospective nature of the study and potential variability in the study center's laboratory protocol(s) compared to other reproductive treatment centers may limit the external validity of our findings. Additionally, patients who transferred euploid embryos, biopsied on day 7 of development due to an absence of day 5 or day 6 counterparts, may have introduced selection bias in this study. WIDER IMPLICATIONS OF THE FINDINGS: Embryonic developmental stage, morphological grade and ploidy status are paramount factors affecting ET selection and implantation potential. This study reveals that embryos ineligible for TE biopsy on day 5 or day 6 of development may benefit from extended culture to day 7. Our study demonstrates patient benefit when extended culture to day 7 of development is routinely performed for embryos failing to meet biopsy criteria by day 5 or 6. STUDY FUNDING/COMPETING INTEREST(S): No funding was received for the realization of this manuscript. Dr Alan Copperman is Advisor or Board Member of Sema 4 (Stake holder in Data), Progyny and Celmatix. TRIAL REGISTRATION NUMBER: This retrospective analysis was approved by an Institutional Review Board (WIRB PRO NUM: 20161791; Study Number: 1167398).

Hatching status before embryo transfer is not correlated with implantation rate in chromosomally screened blastocysts.

STUDY QUESTION: Do the reproductive outcomes from the transfer of fully hatched (FH) blastocysts differ from those of not fully hatched (NFH) blastocysts? SUMMARY ANSWER: Biochemical pregnancy rate (BPR), implantation rate (IR), live birth rate (LBR) and early pregnancy loss (EPL) rate are similar in FH and NFH single euploid blastocyst embryo transfers. WHAT IS KNOWN ALREADY: The use of extended culture and PGS often leads to transfer of an embryo that is well developed and frequently FH from the zona pellucida. Without the protection of the zona, an FH embryo could be vulnerable to trauma during the transfer procedure. To date, no other study has evaluated the reproductive competence of an FH blastocyst transfer. STUDY DESIGN, SIZE, DURATION: The retrospective study included 808 patients who underwent 808 cycles performed between September 2013 and July 2015 at a private academic IVF center. Of these, 436 cycles entailed transfer of a NFH blastocyst (n = 123 fresh transfer, n = 313 frozen/thawed embryo transfer (FET)) and 372 cycles entailed transfer of an FH blastocyst (n = 132 fresh, 240 FET). Fresh and FET cycles and associated clinical outcomes were considered separately. LBR was defined as the delivery of a live infant after 24 weeks of gestation. PARTICIPANTS/MATERIALS, SETTING, METHOD: Trophectoderm biopsies were performed on Day 5 (d5) or 6 (d6) for embryos meeting morphology eligibility criteria (set at ≥3BC). Morphologic grading was determined using a modified Gardner-Schoolcraft scale prior to transfer. A single euploid embryo was selected for transfer per cycle on either the morning of d6, for fresh transfers or 5 days after progesterone supplementation for patients with transfer in an FET cycle. Embryos were classified as NFH (expansion Grade 3, 4 or 5) or FH (expansion Grade 6) cohorts. The main outcome measure was IR. MAIN RESULTS AND THE ROLE OF CHANCE: In the fresh transfer group, IR was similar between NFH and FH cycles (53.7% versus 55.3%, P = 0.99, odds ratio (OR) 0.9; 95% confidence interval (CI) 0.6-1.5). Secondary outcomes were also statistically similar between groups: BPR (65.9% versus 66.7%, OR 1.0; 95% CI: 0.6-1.6), LBR (43.1% versus 47.7%, P = 0.45, OR 1.2; 95% CI: 0.7-1.9) and EPL rate (22.8% versus 18.2%, OR 1.3; 95% CI: 0.7-2.4). After adjusting for age, BMI, endometrial thickness at the LH surge and oocytes retrieved in a logistic regression (LR) model, the hatching status remained not associated with IR (P > 0.05). In the FET cycles, IR was similar between NFH and FH cycles (62.6% versus 61.7%, OR 1.0; 95% CI: 0.7-1.5). Secondary outcomes were similar between groups: BPR (74.1% versus 72.9%, respectively, OR 1.1; 95% CI: 0.7-1.6), LBR (55.0% versus 50.0%, OR 0.8; 95% CI: 0.6-1.1) and EPL rate (18.9% versus 22.9%, respectively, OR 0.8; 95% CI: 0.5-1.2). After adjusting for age, BMI, endometrial thickness at the LH surge and oocytes retrieved in an LR model, the hatching status was not shown to be associated with implantation (P > 0.05). LIMITATIONS, REASONS FOR CAUTION: Limitations include the retrospective design and data from a single institution. Additionally, the study was limited to patients that developed high-quality blastocysts suitable for biopsy. WIDER IMPLICATIONS OF THE FINDINGS: The results suggest that FH embryos are not more fragile or less likely to implant when compared to NFH counterparts. We found no evidence of altered IR or other clinical outcomes in the transfer of FH euploid embryos. STUDY FUNDING/COMPETING INTERESTS: JG is funded by MSTP grant T32 GM007280 (NIH). No additional funding was received. There are no conflicts of interest to declare..

Effect of postthaw change in embryo score on single euploid embryo transfer success rates.

OBJECTIVE: To assess whether the change in embryo morphology from precryopreservation to postthaw is associated with the embryo transfer success rates in single euploid embryo transfer cycles. DESIGN: Retrospective cohort study. SETTING: Academic affiliated fertility clinic. PATIENT(S): Patients who underwent a single euploid embryo transfer cycle from September 2016 to April 2022 were included. A decision support tool was used to assign each embryo a reproductive potential score on the basis of the day of biopsy, expansion, and grade of trophectoderm and inner cell mass at the time of cryopreservation and after thaw. Embryos were divided into 4 groups: group 1 included embryos with the same score after thaw (reference); group 2 included those with a higher score; group 3 included those with a lower score; and group 4 included those that did not re-expand after thaw. INTERVENTION(S): No interventions administered. MAIN OUTCOME MEASURE(S): The primary outcome was the live birth rates (LBRs) per embryo transfer. The secondary outcomes included the chemical pregnancy, clinical pregnancy, and clinical pregnancy loss rates. Comparative statistics and univariate analyses were performed using the Kruskal-Wallis and χ2tests. Multivariate logistic regression fitted with generalized estimating equation was performed to compare the odds of live birth between groups. RESULT(S): A total of 7,750 embryo transfers performed for 4,613 patients met inclusion criteria: 5,331 in group 1; 486 in group 2; 1,726 in group 3; and 207 in group 4. In the univariate analysis, there was a statistically significant difference in the LBR between groups 1, 2, 3, and 4 (55.8% vs. 51.4%, 47.5%, and 26.6%). Logistic regression controlling for oocyte age, antimüllerian hormone, body mass index, endometrial thickness, year of embryo transfer, time from thaw to final grading, and embryo score before cryopreservation showed significantly lower odds of live birth when the embryo was downgraded (odds ratio [OR], 0.70; confidence interval [CI], 0.62-0.79) or did not re-expand (OR, 0.36; CI, 0.26-0.51) than those with no change in score. When controlling for all variables, there was a significant increase in the odds of live birth between embryos that had a higher score after thaw and those without a change (OR, 1.42; CI, 1.14-1.76). There was no significant difference in the clinical pregnancy loss rate among the 4 groups. CONCLUSION(S): The change in the quality of the embryo after thaw is an important factor in embryo transfer success. In an adjusted analysis, the chemical and clinical pregnancy rates and LBR per embryo transfer all significantly decrease in embryos that were downgraded or did not expand on the day of single euploid embryo transfer. Embryos that re-expand and have improved quality after thaw have the highest odds of live birth.

Optimizing human oocyte cryopreservation for fertility preservation patients: should we mature then freeze or freeze then mature?

OBJECTIVE: To evaluate the maturation and post-thaw survival rates of immature oocytes to determine whether in vitro maturation (IVM) should be attempted prior to or after cryopreservation. DESIGN: Nonrandomized observational study. SETTING: Private academic and clinical reproductive center. PATIENT(S): Patients (n = 71) who donated immature unusable oocytes after vaginal oocyte retrieval (VOR) after undergoing controlled ovarian hyperstimulation using a standard GnRH antagonist protocol. INTERVENTION(S): Germinal vesicle (GV), metaphase I (MI), and metaphase II (MII) oocytes (n = 175) were obtained from consenting IVF patients for fresh IVM, post-thaw IVM, or control group. In the fresh IVM group, GV- and MI- stage oocytes (n = 69) were cultured for 24 hours, matured in vitro (IVM-MII), cryopreserved, thawed, and evaluated for survival. In the post-thaw IVM group, GV- and MI- stage oocytes (n = 27) were frozen on day 0, thawed, evaluated for survival, and cultured for 24-hour IVM. MII donor oocytes (n = 79) were cryopreserved and thawed as a control. MAIN OUTCOME MEASURE(S): Survival postfreeze and oocyte development to the MII stage was analyzed using a χ(2) analysis. RESULT(S): Fresh IVM had a significantly higher maturation rate than post-thaw IVM. CONCLUSION(S): Oocyte cryopreservation is important for patients at risk of ovarian cancer, elective fertility preservation, and, potentially, for ovum donation. The superior maturation rate of GV and MI oocytes in the fresh versus post-thaw groups provides strong evidence for maturing oocytes to the MII stage before cryopreservation.

Commercially available enhanced in vitro maturation medium does not improve maturation of germinal vesicle and metaphase I oocytes in standard in vitro fertilization cases.

Improvements in in vitro maturation techniques have focused on culture optimization to increase oocyte maturation rates. Specialized culture media, now commercially available, did not perform significantly better than standard IVF culture media for maturation of immature oocytes in our normal IVF cases.