Factors related to clinical pregnancy after vitrified-warmed embryo transfer: a retrospective and multivariate logistic regression analysis of 2313 transfer cycles

[Clinical outcome after transfer of vitrified blastocysts in relation to freezing indication]

OBJECTIVES

In France, embryo thawing concern 45.8% of attempts at assisted reproductive technologies excluding artificial inseminations. This proportion is constantly increasing for various reasons. The main objective of this study is to compare the live birth rate following frozen blastocyst transfer (FBT) according to the initial indication for freezing.

METHODS

This is a retrospective study including patients who underwent FBT between 01/01/2020 and 06/30/2022 at the Regional University Hospital Center of Tours. The results were compared (univariate and multivariate analyses) between the three main indications for freezing: freezing of the complete cohort of blastocysts for risk of ovarian hyperstimulation (=OHS), freezing of supernumerary blastocysts after fresh blastocyst transfer (BT) with pregnancy (=second request) or without pregnancy (=BT failure). Results have also been described for other indications.

RESULTS

Among the 963 FBT cycles selected, 28% of live births by thawing were obtained, all indications of freezing combined. A significantly lower rate was identified in the FBT failure group compared to the OHS group. However, after adjustment, the results remained significant for the age of the patient on the freezing cycle but not for the indication for freezing.

CONCLUSIONS

The outcome of a FBT does not seem significantly impacted by the indication of freezing considering the confounding factors. The prospective analysis of more data from a multicenter study would be necessary to confirm these results.

Impact of inclusion of a poor-quality embryo with a good-quality embryo on pregnancy outcomes in vitrified-warmed blastocyst transfers

RESEARCH QUESTION

Does the co-transfer of a good-quality embryo and a poor-quality embryo influence pregnancy outcomes in comparison to the transfer of a single good-quality embryo in vitrified-warmed blastocyst transfer cycles?

DESIGN

This retrospective cohort study involved a total of 11,738 women who underwent IVF/intracytoplasmic sperm injection cycles and vitrified-warmed blastocyst transfer at a tertiary-care academic medical from January 2015 to June 2022. The study population was categorized into two groups: single-blastocyst transfer (SBT; participants who underwent single good-quality embryo transfer, n = 9338) versus double-blastocyst transfer (DBT; participants who underwent transfers with a poor and a good-quality embryo, n = 2400).

RESULTS

The live birth rate (LBR) was significantly higher in the DBT group in comparison with the SBT group (65.6% versus 56.3%, P < 0.001). Multivariable logistic regression analysis showed that DBT was an independent predictor for LBR with a strong potential impact (adjusted odds ratio 1.55, 95% confidence interval 1.41-1.71; P < 0.001). However, the multiple birth rate was significantly higher in the good-quality embryo and poor-quality embryo group compared with patients undergoing a single good-quality embryo transfer (41.4% versus 1.8%; P < 0.001).

CONCLUSIONS

In vitrified-warmed blastocyst transfer cycles, LBR was higher following DBT with one good-quality and one poor-quality embryo compared with SBT. However, this was at the expense of a marked increase in the likelihood of multiple gestations. Physicians should still balance the benefits and risks of double-embryo transfer.

Effect of re-cryopreservation on pregnancy and neonatal outcomes: Analysis using propensity score matching

OBJECTIVE

To comprehensively assess the effect of re-cryopreservation procedure on pregnancy and neonatal outcomes by using propensity matching (PSM) analysis.

METHODS

The patients were divided into two groups according to the times of embryo cryopreservation: the cryopreservation group (n = 8034) and the re-cryopreservation group (n = 66). To optimize the precision of the present study, we used PSM to adjust the different baseline characteristics between the two groups, including maternal age, the number of good-quality embryos transferred and endometrial preparation protocols. The primary outcome was live-birth rate. The secondary outcomes were biochemical pregnancy rate, clinical pregnancy rate, and miscarriage rate.

RESULTS

We found that the rates of biochemical pregnancy and clinical pregnancy were comparable between the two groups, whereas miscarriage rate was increased, resulting in significantly reduced live-birth rate in the re-cryopreservation group. No differences were observed in terms of neonatal outcomes, including cesarean section, birth weight, and malformation as well as pregnancy complications. Moreover, multivariable analysis demonstrated that re-cryopreservation was an independent risk factor for live-birth rate.

CONCLUSION

The present study demonstrated the adverse effect of re-cryopreservation on pregnancy outcomes, providing valuable information for clinical decision making and patient counseling.

Elective single versus double blastocyst-stage embryo transfer in women aged 36 years or older: a retrospective cohort study

We evaluated if elective single-blastocyst transfer (eSBT) could be adopted in women aged 36 or older. In this retrospective cohort, women aged ≥36 years received IVF ovarian stimulation cycles and had ≥ two blastocysts. A total of 240 women underwent eSBT and 189 double-blastocyst transfer (DBT) in the first transfer cycle. The subsequent frozen-thawed embryo transfer cycles were a combination of single- and double- blastocyst transfers. Analysis was stratified for patients in age groups 36-37, 38-39 and ≥40, considering the quality of the blastocyst transferred. The cumulative live birth rates (cLBR) were 74.2% (178/240) versus 63.0% (119/189) after eSBT versus DBT, respectively (aOR: 1.09 (0.68, 1.75)). Time to live birth did not vary significantly between the two groups (HR: 0.85 (0.68, 1.08)). The total number of children born was 194 after eSBT (162 singletons and 16 pairs of twins) versus 154 (84 singletons and 35 twins) after DBT. The odds ratios for preterm birth (0.37 (0.21-0.64)), and low birth weight (0.31 (0.16, 0.60)) were all lower in eSBT. In women aged ≥36 years, cLBR following single- versus double- blastocyst transfer was comparable while the odds of multiple live births and adverse perinatal outcomes were reduced.

Optimal number of high-quality cleavage-stage embryos for extended culture to blastocyst-stage for transfer in women 38 years and older

PURPOSE

We aimed to evaluate the pregnancy outcomes of cleavage-stage embryo transfers (ETs) for the first time and explore optimal number of high-quality cleavage-stage embryos for extended culture to blastocyst-stage in women of advanced maternal age (AMA).

METHODS

We retrospectively identified 1646 AMA women ≥ age 38 years for the first fresh ETs between January 2014 and December 2020 at our hospital. Double ETs were divided into three groups as follows: DET-HH (two high-quality embryos), DET-HL (one high-quality and one low-quality embryo), and DET-LL (two low-quality embryos) groups. We mainly analyzed the pregnancy outcomes of double cleavage-stage ETs with different embryo grades and blastocyst-stage ETs with different number of high-quality cleavage-stage embryos on day 3.

RESULTS

Our data indicated that the DET-HH group had significantly higher clinical pregnancy, ongoing pregnancy, and live birth rates than DET-HL and DET-LL groups (p < .05). For extended culture to blastocyst-stage with 2 (D3-2H), 3 (D3-3H), and 4 (D3-≥4H) high-quality cleavage-stage embryos, the D3-≥ 4H group had significantly higher ongoing pregnancy and live birth rates than D3-2H and D3-3H groups (p < .05). We observed that the number of high-quality embryos on day 3 was independently associated with live birth rate for blastocyst transfers (OR: 1.133, 95% CI 1.023-1.256, p = .017). There were no significant differences in the clinical pregnancy, ongoing pregnancy and live birth rates among DET-HH, D3-2H and D3-3H groups (p > .05).

CONCLUSIONS

Extended culture to blastocyst-stage for transfer was safe and recommended for AMA women with ≥ 4 high-quality embryos on day 3.

Patient- and cycle-specific factors affecting the outcome of frozen-thawed embryo transfers

PURPOSE

This study attempted at identifying the main parameters influencing the outcome of frozen embryo transfers.

METHODS

This is a single-center retrospective cohort study of 830 frozen-embryo-transfer cycles performed at a German university hospital from January 2012 to December 2016. Main outcome parameters were the clinical pregnancy and live birth rate. Twelve patient- and cycle-dependent factors were analyzed in terms of their influence on the outcome of frozen embryo transfers. Multivariate logistic regression analysis was used for the modelling of the dependency of the different parameters on outcomes.

RESULTS

The clinical pregnancy rate in our study was 25.5%, the live birth rate was 16.1% with an average maternal age of 34.2 years at the time of the oocyte retrieval. In the univariate analysis age, number of transferred embryos, blastocyst versus cleavage stage transfer, embryo quality and mode of endometrial preparation affected the birth rate significantly. The birth rate after artificial endometrial preparation was significantly lower than the birth rate after transfers in modified natural cycles (12.8 versus 20.6% with p = 0.031). The multivariate logistic regression analysis showed a significant independent influence of age, number of transferred embryos, culture duration and mode of endometrial preparation on the frozen embryo transfer success rates. Body mass index, nicotine abuse, a history of PCO syndrome or endometriosis and the co-transfer of a second poor-quality embryo to a good-quality embryo appeared to be irrelevant for the outcome in our collective.

CONCLUSION

Age, number of transferred embryos, embryo culture duration and the mode of endometrial preparation are independent predictive factors of frozen embryo transfer outcomes.

Effect modification by developmental stage of embryos on the association between late follicular phase progesterone elevation and live birth in fresh transfers

BACKGROUND

Late follicular phase progesterone elevation (LFPE) during ovarian stimulation is associated with reduced live birth rates (LBRs) after cleavage-stage embryo transfer. However, due to better synchronization with a stimulated endometrium, prior studies shown that LFPE had no effect on transferring embryos at blastocyst stage. The study aim to exam whether the developmental stage of embryos and serum progesterone levels on the day of human chorionic gonadotropin (hCG) administration jointly affect the odds of live birth in fresh fresh IVF/intracytoplasmic sperm injection (ICSI) cycles.  METHODS: The single-center retrospective cohort study included a total of 4,471 fresh embryo transfer cycles with 2,342 at cleavage stage versus 2,129 at blastocyst stage. Patients underwent IVF/ICSI with ovarian stimulation in gonadotropin-releasing hormone antagonist protocol. The serum progesterone level was examined both as a continuous variable and as a categorical variable by quartiles. Analysis was performed using the generalized estimating equations framework and multivariate regression models.

RESULTS

LBRs were inversely associated with progesterone as a continuous variable on the day of hCG in both the cleavage-stage (crude OR 0.87, 95%CI 0.73-1.03; adjusted OR 0.80, 95% CI 0.65-0.98) and the blastocyst-stage (crude OR 0.66, 95%CI 0.56-0,78; adjusted OR 0.61, 95%CI 0.50-0.73) groups. The interaction testing was highly significant (P = 0.018) indicating an effect modifying role of stage of embryos transferred on the association of pregesterone values with the LBRs in fresh cycles. A similar pattern for a greater reduction in ORs for live birth in cycles with blastocysts transfer was also observed when progesterone was analyzed by interquartile ranges. The findings remained unchanged in subgroup analysis stratified by types of ovarian response.

CONCLUSIONS

In fresh cycles, detrimental effect of late follicular phase progesterone elevation on live birth was more prominent in blastocyst-stage group compared with that in clevaged-stage group.

Live birth rate following frozen-thawed blastocyst transfer is higher in high-grade day 6 blastocysts than in low-grade day 5 blastocysts

Background

Day 5 (D5) blastocysts are generally given priority to transfer than day 6 (D6) blastocysts; however, which one should be prioritized to transfer when only low-grade D5 and high-grade D6 blastocysts are available?

Methods

A large retrospective cohort study was carried out to evaluate the live birth rate (LBR) following D5 and D6 blastocysts in single frozen-thawed blastocyst transfer (FBT) during January 2014 and December 2018. A multivariate logistic regression was conducted to evaluate the combined impact of expansion day (D5 and D6) and blastocyst quality (high grade/low grade) on LBR, accounting for the potential confounding factors. The biopsied blastocysts from a consecutive PGT-A case series during February 2013 to December 2021 were analyzed in a supplementary study.

Results

The LBR achieved in high-grade D6 blastocyst transfer was significantly higher than that in low-grade D5 blastocyst transfer (50.43% vs. 40.70%, aOR 1.54, 95% CI 1.05-2.26, p = 0.027). There were no significant differences in preterm birth rate, very preterm birth rate, mean live birth weight, and birth weight <1,500 g and >4,000 g between the two cohorts. As for aneuploidy analysis in PGT, there were 54.55% of euploid blastocysts (30/55) among high-grade D6 blastocysts, significantly higher than the 41.39% of euploid blastocysts (565/1,365) among low-grade D5 blastocysts (p < 0.001).

Conclusions

Our data suggest that D6 blastocysts with high morphology grading are preferred than D5 blastocysts with low morphology grading when selecting blastocyst transfer to shorten the time of conception.

Comparing the success rate of natural cycle and modified natural cycle protocols for frozen-thawed embryo transfer

Objective: The aim of the present study is to compare the effects of Natural Cycle and modified Natural Cycle protocols for frozen-thawed embryo transfer on clinical pregnancy rate and live birth rate. Methods: This prospective randomized controlled trial comprised 145 patients scheduled for frozen-thawed embryo transfer and was conducted at a university hospital between 2019 and 2021. The Natural Cycle protocol was administered to 73 patients and the modified Natural Cycle protocol to 72 patients and the clinical outcome was compared between the groups. The main outcome measure was live birth rate. Results: Baseline characteristics and cycle parameters were similar in both groups. There was no difference in clinical pregnancy rate (58.9% and 54.2%, respectively; p = .565) and live birth rate between the Natural Cycle and modified Natural Cycle groups (49.3% and 48.6% respectively; p = .932). Conclusion: This study established that clinical pregnancy and live birth rates were not affected by natural cycle ovulation being spontaneous or hCG-triggered among patients undergoing frozen-thawed embryo transfer. Thus, the protocol for natural cycle frozen-thawed embryo transfers should be chosen according to the priorities of the patient and the physician.

Duration of infertility and assisted reproductive outcomes in non-male factor infertility: can use of ICSI turn the tide?

Background

Intracytoplasmic sperm injection (ICSI) is increasingly used among in vitro fertilization (IVF) cycles without male factor infertility. For couples with prolonged infertility duration, the preferred insemination method may vary across laboratories and clinics. We analyzed whether ICSI is effective for non-male factor infertility with long infertility duration.

Methods

Seventeen thousand four hundred seventy-seven IVF/ICSI cycles from women with non-male factor infertility were included, of these 4177 women with infertility duration ≥ 5 years were in the final analysis. Primary outcome was the live birth rate after first embryo transfer. Secondary outcomes were rates of clinical pregnancy and fertilization.

Results

A nonlinear relationship was observed between infertility duration and IVF fertilization rate, which decreased with infertility years up to the turning point (4.8 years). 4177 women with infertility ≥ 5 years were categorized by IVF (n = 3806) or ICSI (n = 371). Live birth rate after first embryo transfer was 43.02% in ICSI and 47.85% in IVF group (adjusted odds ratio (aOR), 0.91; 95% confidence interval (CI), 0.72–1.15). Fertilization rate per metaphaseII (aOR, 1.10; 95% CI, 0.86–1.40) and clinical pregnancy rate (aOR, 0.89; 95% CI, 0.71–1.13) were similar between the two groups. Sensitive analyses (women ≥ 35 years) did not show a benefit of ICSI over IVF.

Conclusions

Women with infertility exceeding 4.8 years had decreased incidence of IVF fertilization. The use of ICSI showed no significant improvement in fertilization and live birth rates for non-male factor couples with ≥ 5 years of infertility.

Risk of spontaneous abortion after antibiotic therapy for chronic endometritis before in vitro fertilization and intracytoplasmic sperm injection stimulation

OBJECTIVE

To investigate whether cured chronic endometritis (CE) from antibiotic treatment would be associated with a higher risk of spontaneous abortion in the following in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) treatment.

DESIGN

Prospective cohort study.

SETTING

Tertiary reproductive medicine center.

PATIENT(S)

Patients with infertility who underwent a routine hysteroscopy underwent an IVF/ICSI stimulation between January 1, 2019, and December 31, 2020. Women with CE (N = 338) underwent antibiotic therapy, and the assisted reproductive outcomes were then compared with women without CE (N = 7,962).

INTERVENTION(S)

Chronic endometritis was diagnosed through hysteroscopy and confirmed by histology and immunohistochemistry for CD138.

MAIN OUTCOME MEASURE(S)

Spontaneous abortion rate after the initial embryo transfer.

RESULT(S)

A total of 7,218 patients underwent embryo transfer, with 330 in the cured CE group and 6,888 in the non-CE group. Women with cured CE had a higher rate of spontaneous abortion than did those without CE (11.8% vs. 9.2%; crude odds ratio [OR], 1.32 [0.94, 1.86]), and this difference was statistically significant after adjusting for confounding variables (adjusted OR, 1.49 [1.01, 2.19]). The live birth rate was 43.9% in the cured CE group and 50.5% in the non-CE group (crude OR, 0.77 [0.62, 0.96]; adjusted OR, 0.73 [0.59, 0.92]). The incidence of clinical pregnancy did not differ significantly between the 2 groups (56.1% vs. 60.0%; crude OR, 0.85 [0.68, 1.06]; adjusted OR, 0.83 [0.66, 1.03]). Sensitivity analyses stratified by initial fresh- or frozen-thawed embryo transfer cycles resulted in similar results.

CONCLUSION(S)

Chronic endometritis cured with antibiotic therapy was associated with an increased risk of spontaneous abortion among women undergoing IVF/ICSI treatment. The interpretation of the findings is limited by a potential confounding bias.

Ultralow Oxygen Tension (2%) Is Beneficial for Blastocyst Formation of In Vitro Human Low-Quality Embryo Culture

Objectives

To investigate whether a reduction in the O₂ tension from 5 to 2% during extended culture from day 3 onwards was beneficial to human blastocyst development in vitro.

Methods

We firstly identified 139 patients who had no low-quality embryos on day 3, and all the embryos were prolonged to culture on day 5 or 6. We mainly analyzed 188 patients receiving IVF/ICSI-ET for the first time, and no high-quality embryos were obtained on day 3 from January 2018 to December 2019. After transferred with one or two low-quality embryos, extended culture was performed under low O₂ (5%) or ultralow O₂ (2%) tension for surplus embryos. 296 embryos from 106 patients were continued to culture under 5% O₂ tension, and 214 embryos from 82 patients were continued to culture under 2% O₂ tension. Main outcomes compared were blastulation and high-quality blastulation rates.

Results

We observed no significant differences in the blastulation and high-quality blastulation rates for high-quality cleavage-stage embryos between 2% and 5% O₂ groups (p > 0.05). For low-quality cleavage-stage embryos, we observed that the 2% O₂ group showed a significantly higher blastulation (39.72 versus 31.08%; p = 0.043) rate than that in the 5% O₂ group. The high-quality blastocyst formation rate (10.75 versus 8.45%; p = 0.380) was comparable between the 2% and 5% O₂ groups. The blastulation rate reached 44.86% by culturing blastocysts an additional day under 2% O₂ tension which was significantly higher than that (32.09%) under 5% O₂ tension (p < 0.05).

Conclusion

A reduction in O₂ tension from 5 to 2% after day 3 might be beneficial to the patients with no high-quality embryos. Extended culture to day 7 under 2% O₂ tension increased the number of available blastocysts per IVF/ICSI cycle and was worth recommending especially for patients with few blastocysts.

Sex ratio imbalance following blastocyst transfer is associated with ICSI but not with IVF: an analysis of 14,892 single embryo transfer cycles

PURPOSE

Assisted reproductive technology (ART) has an impact on secondary sex ratio (SSR), which is seemed to be elevated after blastocyst transfer (BT) but decreased following ICSI procedure. We aim to assess whether the higher SSR associated with BT could be influenced by fertilization method used.

METHODS

All consecutive IVF/ICSI cycles (fresh and frozen) involving single embryo transfer (SET) resulting in a live birth between 2015 and 2019 were retrospective analyzed. Logistic regression was used to model the effect on the SSR of maternal and specific ART characteristics.

RESULTS

Six thousand nine hundred twenty-two women were included with the crude SSR of 54.8%. The impact of BT on SSR is influenced by the fertilization method used. After adjustment for potential confounders, the SSR in the ICSI BT group was significantly higher when compared to ICSI cleavage-stage embryo SET (aOR 1.24; 95% CI 1.10-1.40, P < 0.001). However, this effect was not detected among SBT with IVF treatment (aOR 1.04; 95% CI 0.97-1.12, P = 0.260). Assessing blastocyst morphological parameters, high trophectoderm quality was significantly associated with elevated SSR (aOR 1.76, 95% CI 1.34-2.31 [A vs. C], and aOR 1.28, 95% CI 1.14-1.44 [B vs. C]). No significant difference was shown in expansion, inner cell mass, or days of blastocyst formation between male and female blastocysts.

CONCLUSIONS

The impact of BT on SSR could be influenced by the fertilization method used. The higher SSR was observed after BT with ICSI procedures but not with IVF. Interpretation of the findings is limited by the potential for selection and confounding bias.

Is Human Chorionic Gonadotropin Trigger Beneficial for Natural Cycle Frozen-Thawed Embryo Transfer?

Objective: The aim of this study is to investigate, in ovulatory patients, whether there is a difference in reproductive outcomes following frozen-thawed embryo transfer (FET) in natural cycles (NC) compared to modified natural cycles (mNC).

Methods: This retrospective cohort study, performed at the public tertiary fertility clinic, involved all infertile patients undergoing endometrial preparation prior to FET in NC and mNC from January, 2017 to November, 2020. One thousand hundred and sixty-two patients were divided into two groups: mNC group (n = 248) had FET in a NC after ovulation triggering with human chorionic gonadotropin (hCG); NC group (n = 914) had FET in a NC after spontaneous ovulation were observed. The primary outcome was live birth rate. All pregnancy outcomes were analyzed by propensity score matching (PSM) and multivariable logistic regression analyses.

Results: The NC group showed a higher live birth rate [344/914 (37.6%) vs. 68/248 (27.4%), P = 0.003; 87/240 (36.3%) vs. 66/240 (27.5%), P = 0.040] than the mNC group before and after PSM analysis. Multivariable analysis also showed mNC to be associated with a decreased likelihood of live birth compared with NC [odds ratio (OR) 95% confidence interval (CI) 0.71 (0.51–0.98), P = 0.039].

Conclusion: For women with regular menstrual cycles, NC-FET may have a higher chance of live birth than that in the mNC-FET cycles. As a consequence, it's critical to avoid hCG triggering as much as possible when FETs utilize a natural cycle strategy for endometrial preparation. Nevertheless, further more well-designed randomized clinical trials are still needed to determine this finding.

The effect of endometrial thickness and pattern on the success of frozen embryo transfer cycles and gestational age accuracy

OBJECTIVE

To evaluate the relationship between endometrial thickness measured before embryo transfer, and pregnancy outcomes in frozen-thawed embryo transfer (FET).

METHODS

We retrospectively analyzed outcomes of all consecutive FET cycles, from January 2012 to August 2018. Based on ROC analysis for endometrial thickness, we found 8 mm was a reliable cutoff point to predict pregnancy prior to embryo transfer. Accordingly, the cycles were divided into Group A: cycles with endometrial thickness ≤ 8 mm and Group B: > 8 mm.

RESULTS

Group A included 485 FET cycles and group B included 626 cycles. Compared with group A, Group B had significantly higher chemical and clinical pregnancy rates (30.3 vs. 24.6%; p = .046, and 24.0 vs. 18.6%; p = .036), respectively. In multivariate analysis, endometrial thickness and the protocols used were the only parameters influencing the chance to achieve pregnancy, with odds ratio 1.54 (95%CI 1.07-2.22, p = .019) for the endometrium and odds ratio 1.95 (95%CI 1.31-2.9; p = .001) to the protocol used. Endometrial thickness might predict crown-rump length (CRL) discordancy with odds ratio 4.61 (p = .001; 95% CI 1.42-14.92). Compared with group B, Group A had more cases of overt discordancy (13.3 vs. 4%; p = .016).

CONCLUSIONS

For patients undergoing FET cycles, endometrial thickness and treatment protocol may predict the chemical and clinical pregnancy rates, as well as CRL discordancy.

SUMMARY

Endometrial thickness and preparation improved pregnancy rate in FET cycles and significantly greater crown-rump length discordancy was observed with thinner endometria.

Effects of three pro-nuclei (3PN) incidence on laboratory and clinical outcomes after early rescue intracytoplasmic sperm injection (rescue-ICSI): an analysis of a 5-year period

OBJECTIVES

We aimed to explore the effect of three pro-nuclei (3PN) incidence on laboratory and clinical outcomes after early rescue intracytoplasmic sperm injection (rescue-ICSI).

METHODS

This study included 509 early rescue-ICSI cycles from February 2014 to February 2019. The patients were divided into 3PN = 0% (394 cycles) and 3PN > 0% (115 cycles) group. Main outcomes compared were good quality embryo, available embryo, implantation (IR), clinical pregnancy (CPR), abortion (AR) and live birth rates (LBR).

RESULTS

There were no significant differences in the basal characteristics between two groups (p > .05). We observed that 3PN = 0% and 3PN > 0% groups had similar good quality embryo (47.02 versus 46.80%; p = .917) and available embryo (83.28 versus 81.37%; p = .247) rates. Our results showed that the IR (47.26 versus 51.05%; p = .357), CPR (61.17 versus 66.08%; p = .338) and LBR (52.80 versus 50.43%; p = .656) were comparable between 3PN = 0% and 3PN > 0% groups. The 3PN = 0% group showed significantly lower AR than that in the 3PN > 0% group (11.20 versus 21.05%; p = .029; OR 2.114; 95% CI 1.069-4.178).

CONCLUSIONS

3PN incidence made negative effects on the clinical outcomes after early rescue-ICSI.

Day 3 time lapse selection is beneficial for the patients with no good-quality embryos

We aimed to evaluate whether or not time lapse selection was beneficial for the cleavage-stage embryo transfers. The study included 838 infertile women with good ovarian reserve (obtaining more than 8 oocytes) from January 2018 to August 2019. Based on the transferred embryos with different grades (grade I, II and III), the patients were divided into day 3 selection with conventional morphology (CM) and day 3 selection with time lapse (TL) groups. For the grade I and II embryos, we observed that CM and TL had similar implantation, clinical pregnancy and ongoing pregnancy (p > .05) rates. For the grade III embryos, we observed that CM group showed slightly lower implantation (36.74 versus 41.03%, p = .261) and clinical pregnancy (56.82 versus 64.10%, p = .182) rates than TL group. CM group showed significantly lower ongoing pregnancy (47.35 versus 59.83%, p = .025) rate than TL group. And we observed that CM group had significantly higher blastulation (38.93 versus 26.61%, p = .019) rate than TL group. We concluded that TL selection was beneficial to the patients with no good-quality embryos in the first cleavage-stage embryo transfers.

Early and late pregnancy loss in women with polycystic ovary syndrome undergoing IVF/ICSI treatment: a retrospective cohort analysis of 21 820 pregnancies

OBJECTIVE

To examine early and late pregnancy loss in women with and without polycystic ovary syndrome (PCOS) undergoing IVF/ICSI transfers.

DESIGN

Retrospective cohort study.

SETTING

Reproductive medicine centre at a tertiary hospital.

POPULATION

We studied women with a positive β-human chorionic gonadotropin (β-hCG) after in vitro fertilisation/intra-cytoplasmic sperm injection (IVF/ICSI) treatment from May 2014 to April 2019.

METHODS

Odds ratios (OR) for early (≤13 weeks) and late (>13 weeks) pregnancy loss were calculated among women with and without PCOS for plurality of the pregnancy with adjustment for confounding factors.

MAIN OUTCOME MEASURES

Early pregnancy loss (EPL) and late pregnancy loss (LPL).

RESULTS

From 21 820 women identified with a positive β-hCG, 2357 (10.8%) women had PCOS, and 19 463 (89.2%) women did not. EPL occurred in 16.6% (391) of women with PCOS versus 18.3% (3565) in women with non-PCOS (OR 0.89, 95% CI 0.79-0.99, P = 0.04). After adjustment for age and other confounders, the rate of EPL was not statistically significantly associated with PCOS status (adjusted OR [aOR] 0.91, 95% CI 0.80-1.05). Women with PCOS demonstrated a higher rate of LPL (6.4% in PCOS versus 3.6% in non-PCOS, OR 1.81, 95% CI 1.48-2.21, P < 0.001). In multivariable analysis, the potential impact of PCOS was less strong (aOR 1.38, 95% CI 0.96-1.98), with BMI and maternal comorbidities also associated with LPL (aOR 1.08, 95% CI 1.04-1.1 and aOR 2.07, 95% CI 1.43-3.00, respectively).

CONCLUSIONS

Polycystic ovary syndrome was not independently associated with EPL. There was an increased risk of LPL but this difference was not statistically significant.

TWEETABLE ABSTRACT

Polycystic ovary syndrome women are at increased risk of late pregnancy loss, partly driven by elevated BMI and maternal comorbidities.

Comparison of Multivariable Logistic Regression and Other Machine Learning Algorithms for Prognostic Prediction Studies in Pregnancy Care: Systematic Review and Meta-Analysis

BACKGROUND

Predictions in pregnancy care are complex because of interactions among multiple factors. Hence, pregnancy outcomes are not easily predicted by a single predictor using only one algorithm or modeling method.

OBJECTIVE

This study aims to review and compare the predictive performances between logistic regression (LR) and other machine learning algorithms for developing or validating a multivariable prognostic prediction model for pregnancy care to inform clinicians' decision making.

METHODS

Research articles from MEDLINE, Scopus, Web of Science, and Google Scholar were reviewed following several guidelines for a prognostic prediction study, including a risk of bias (ROB) assessment. We report the results based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were primarily framed as PICOTS (population, index, comparator, outcomes, timing, and setting): Population: men or women in procreative management, pregnant women, and fetuses or newborns; Index: multivariable prognostic prediction models using non-LR algorithms for risk classification to inform clinicians' decision making; Comparator: the models applying an LR; Outcomes: pregnancy-related outcomes of procreation or pregnancy outcomes for pregnant women and fetuses or newborns; Timing: pre-, inter-, and peripregnancy periods (predictors), at the pregnancy, delivery, and either puerperal or neonatal period (outcome), and either short- or long-term prognoses (time interval); and Setting: primary care or hospital. The results were synthesized by reporting study characteristics and ROBs and by random effects modeling of the difference of the logit area under the receiver operating characteristic curve of each non-LR model compared with the LR model for the same pregnancy outcomes. We also reported between-study heterogeneity by using τ2 and I2.

RESULTS

Of the 2093 records, we included 142 studies for the systematic review and 62 studies for a meta-analysis. Most prediction models used LR (92/142, 64.8%) and artificial neural networks (20/142, 14.1%) among non-LR algorithms. Only 16.9% (24/142) of studies had a low ROB. A total of 2 non-LR algorithms from low ROB studies significantly outperformed LR. The first algorithm was a random forest for preterm delivery (logit AUROC 2.51, 95% CI 1.49-3.53; I2=86%; τ2=0.77) and pre-eclampsia (logit AUROC 1.2, 95% CI 0.72-1.67; I2=75%; τ2=0.09). The second algorithm was gradient boosting for cesarean section (logit AUROC 2.26, 95% CI 1.39-3.13; I2=75%; τ2=0.43) and gestational diabetes (logit AUROC 1.03, 95% CI 0.69-1.37; I2=83%; τ2=0.07).

CONCLUSIONS

Prediction models with the best performances across studies were not necessarily those that used LR but also used random forest and gradient boosting that also performed well. We recommend a reanalysis of existing LR models for several pregnancy outcomes by comparing them with those algorithms that apply standard guidelines.

TRIAL REGISTRATION

PROSPERO (International Prospective Register of Systematic Reviews) CRD42019136106; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=136106.

Clinical Outcomes of Frozen-Thawed Embryo Transfer in Natural Cycles with Spontaneous or Induced Ovulation: a Retrospective Cohort Study from 1937 Cycles

Our objective was to assess whether there is a difference in the pregnancy outcomes in the natural cycle (NC) with spontaneous LH rise compared with modified natural cycle controlled by hCG for final oocyte maturation and ovulation after frozen-thawed embryo transfer (FET). In this retrospective cohort study, we analyzed the clinical outcomes of a total of 1937 patients undergoing FET followed by endometrial preparation with the natural cycle and modified natural cycle. The primary outcome was live birth, and secondary outcomes included miscarriage rate, clinical pregnancy rate, preterm birth rate, and ectopic pregnancy rate. The type of endometrial preparation did not impact live birth (adjusted odds ratio [aOR] 0.92; 95% confidence interval [CI], 0.69-1.23), miscarriage (aOR 0.83; 95%CI, 0.50-1.39), clinical pregnancy (aOR 0.88; 95%CI, 0.66-1.18), preterm birth (aOR 0.91; 95%CI, 0.56-1.50), or ectopic pregnancy (aOR 1.06; 95%CI, 0.29-3.94). In conclusion, in women undergoing FET, natural cycles and modified natural cycles resulted in comparable clinical outcomes.

Reproductive outcomes with donor sperm in couples with severe male-factor infertility after intracytoplasmic sperm injection failures

PURPOSE

To evaluate reproductive outcomes of artificial insemination and IVF with donor sperm (AID or IVF-D) for male-factor couples with a history of unsuccessful ICSI attempt.

METHODS

This retrospective cohort includes couples with severe male-factor infertility who failed ICSI treatment, and subsequently underwent semen donation treatment. We report the following outcomes: (1) live birth rates in AID and IVF-D treatment for couples with severe male infertility factors and prior ICSI failures; (2) paternal impact on embryo development of the same oocyte cohort; (3) prognostic factors in obtaining a live birth with donor semen.

RESULTS

Of 92 women with failed ICSI cycles (26 with multiple attempts), 45 couples underwent AID treatment. Live birth rate per cycle of AID was 18.9%. Fifty-three patients underwent IVF-D including 6 couples who previously did not conceive with AID. Embryological outcomes including fertilization, viable cleavage embryos, and blastocyst formation rates were significantly lower in ICSI cycles with partner sperm compared with IVF-D (P < 0.01). Logistic regression analysis showed that female age and the severity of spermatogenetic disorder are prognostic factors in obtaining a live birth with donated sperm.

CONCLUSION

Couples with severe male infertility factor (azoospermia or extreme oligoasthenospermia) and a history of unsuccessful ICSI cycles benefit from treating with donor sperm. ICSI fertilization, embryo viability, and progression of the embryo to the blastocyst stage are significantly deteriorated by semen parameters. The prognostic factors identified may help couples plan their treatment and prepare for their parenthood journey.

Cumulative Live Birth Rates According to Maternal Body Mass Index After First Ovarian Stimulation for in vitro Fertilization: A Single Center Analysis of 14,782 Patients

Objective: To investigate the cumulative live birth rates (CLBR) according to body mass index (BMI) in women undergoing their first in vitro fertilization (IVF). Design: Retrospective cohort analysis. Setting: An IVF clinic in a public hospital. Patients: This is a retrospective study of 14,782 patients undergoing their first fresh IVF cycles and subsequent frozen embryo transfers in our clinic from January 2014 to January 2017. The follow-up for CLBR continued until January 2019. Patients with a BMI <18.5 kg/m2 were considered to be underweight and those with a BMI > 24 kg/m2 were considered to be overweight. Patients with a BMI ≥ 28 kg/m2 were considered to be obese. Intervention(s): None. Primary Outcome Measure: The primary outcome was cumulative live birth rate (CLBR). Result(s): This study illustrated the "inverted U shape" associations between body weight and IVF outcome (CLBR). The turning points in threshold analysis, as found by an automatic search, were BMIs of 18.5 and 30.4 kg/m2. The main finding of this retrospective data analysis is that the CLBR increased in underweight women, plateaued for normal weight and overweight women with a BMI between 18.5 and 30.4 kg/m2, and decreased in obese women. Conclusion(s): The data suggested an "inverted U shape" association between BMI and CLBR. The CLBR increases in underweight women, plateaus in normal weight and overweight women, and then decreases in obese women.

The impact of endometrial thickness change after progesterone administration on pregnancy outcome in patients transferred with single frozen-thawed blastocyst

BACKGROUND

The aim of this study was to explore the impact of endometrial thickness change after progesterone administration on pregnancy outcome in patients transferred with single frozen-thawed blastocyst.

METHODS

This observational cohort study included a total of 3091 patients undergoing their first frozen-thawed embryo transfer (FET) cycles between April 2015 to March 2019. Endometrial thickness was measured by trans-vaginal ultrasound twice for each patient: on day of progesterone administration, and on day of embryo transfer. The change of endometrial thickness was recorded.

RESULTS

Regardless of endometrial preparation protocol (estrogen-progesterone/natural cycle), female age, body mass index (BMI), and infertility diagnosis were comparable between patients with an increasing endometrium on day of embryo transfer and those without. However, clinical pregnancy rate increases with increasing ratio of endometrial thickness. Compared with patients with Non-increase endometrium, those with an increasing endometrium on day of embryo transfer resulted in significantly higher clinical pregnancy rate (56.21% vs 47.13%, P = 0.00 in estrogen-progesterone cycle; 55.15% vs 49.55%, P = 0.00 in natural cycle).

CONCLUSIONS

In most patients, endometrial thickness on day of embryo transfer (after progesterone administration) increased or kept being stable compared with that on day of progesterone administration. An increased endometrium after progesterone administration was associated with better pregnancy outcome.

Serum estradiol level on trigger day impacts clinical pregnancy rate in modified natural frozen embryo transfer cycles

OBJECTIVE

To examine the predictive value of serum estradiol and progesterone on the day of human chorionic gonadotropin (hCG) administration and embryo transfer for clinical pregnancy rate in modified natural-cycle frozen embryo transfer (NC-FET).

METHODS

In a longitudinal prospective study, all eligible women who underwent NC-FET cycles with hCG triggering in Royan Institute, Tehran, Iran, from June 1, 2015, to December 31, 2016, were evaluated. Serum estradiol and progesterone levels were measured at menstrual cycle initiation, on day of trigger with hCG, on day of embryo transfer, and in pregnant women every 7 days until the observation of a gestational sac with embryonic heartbeat.

RESULTS

In total, 101 modified natural FET cycles were assessed, and the clinical pregnancy and live birth rates achieved were 34 (33.6%) and 32 (31.6%), respectively. The changes in estradiol level during early pregnancy showed an increase by an average of 200 pg/mL per week. Multivariable logistic regression analysis showed that only the estradiol level on the hCG day was a significant predictive variable for clinical pregnancy following NC-FET (P=0.04).

CONCLUSION

Estradiol level on the day of hCG trigger predicted the clinical pregnancy rates after modified NC-FET; this likely mirrored the developmental competence of the corpus luteum and an appropriate luteal structure-function.

Cumulative Live Birth Rates of Good and Low Prognosis Patients According to POSEIDON Criteria: A Single Center Analysis of 18,455 Treatment Cycles

Objective: To investigate the characteristics and outcomes of low prognosis patients defined by POSEIDON criteria undergoing IVF treatment. Design: Retrospective cohort analysis. Setting: An IVF clinic in a public hospital. Patients: 18,455 fresh aspirated IVF cycles with subsequently frozen embryo transfer from Jan 2014 to Jan 2017 in a single IVF clinic were included in the analysis. The low prognosis patients were categorized into 4 groups based on POSEIDON criteria: group 1: age < 35, antral follicle count (AFC) ≥ 5, number of oocytes retrieved ≤ 9 in the previous cycle; group 2: age ≥ 35, AFC≥5, number of oocytes retrieved ≤ 9 in the previous cycle; group 3: age < 35, AFC < 5; group 4: age ≥ 35, AFC < 5. The non-low prognosis patients: group 5: AFC ≥ 5, previous number of oocytes retrieved > 9 oocytes; group 6: AFC ≥ 5, no previous ovarian stimulation. Intervention(s): None. Main Outcome Measure: The primary outcome was cumulative live birth rate (CLBR). Result(s): Taking group 1 as reference, the CLBR from young women in group 3 (35.5%, OR 0.9, 95% CI 0.7-1.2) was slightly lower than that in group 1 (44.6%, p = 0.615). The CLBR in group 2 (24.5%, OR 0.6, 95% CI 0.4-0.8, p = 0.004) and group 4 (12.7%, OR 0.4, 95% CI 0.3-0.6, p < 0.001) was significant lower than that in group 1. In non-poor prognosis patients, the CLBR from young women in group 5 (53.5% OR 1.3 95% CI 0.9, 1.7, p = 0.111) was a slight higher than the reference group 1 while the highest CLBR was originated from the first IVF patients with good ovarian reserve in group 6 (66.9%, OR 2.0, 95% CI 1.6, 2.4). Conclusion(s): The CLBRs and implantation rates in the young women (group 3) with diminished ovarian reserve was similar in those young women (group 1), and was significantly higher than in advanced age women with a fair ovarian reserve (group 2). Though patients in group 2 had better ovarian reserve, more oocytes and more embryos, the pregnancy outcome was inferior to that of group 3 patients with poorer ovarian reserve, fewer oocytes and fewer embryos.

Do day-3 embryo grade predict day-5 blastocyst transfer outcomes in patients with good prognosis?

The main aim was to investigate whether or not day-3 embryo grade could predict day-5 blastocyst transfer outcomes in patients with good prognosis. This study included 233 elective single blastocyst transfers (eSBT) by D5 selection with conventional morphology (CM) and 121 elective single blastocyst transfers (eSBT) by D5 selection with time-lapse monitoring system (TL) from October 2016 to October 2017. All the patients were submitted to controlled ovarian stimulation (COS) with long-term protocol and transferred for the first time. The main outcome measures were clinical pregnancy rates (CPR) and ongoing pregnancy (OPR). Our results suggested that CPR (58.04 versus 57.89 versus 55.56%; p = .957) and OPR (66.07 versus 65.79 versus 64.44%; p = .981) were comparable among day 3 grades I, grades II, and grades III groups. We also observed that the TL group showed a slightly better CPR and OPR than CM group (p > .05). Our findings suggested that good or poor embryos at day-3 were not predictive of the outcomes of good-quality blastocysts in a good-prognosis population. It needed to be emphasized that time-lapse monitoring might be useful for elective single blastocyst transfer.

Combined analysis of endometrial thickness and pattern in predicting clinical outcomes of frozen embryo transfer cycles with morphological good-quality blastocyst: A retrospective cohort study

To evaluate the combined effect of endometrial thickness and pattern on clinical outcomes in females following in vitro fertilization/intracytoplasmic sperm injection and frozen-thawed embryo transfer (IVF/ICSI-FET).FET cycles using at least 1 morphological good-quality blastocyst conducted between 2012 and 2013 at a university-based reproductive center were reviewed retrospectively. Endometrial ultrasonographic characteristics were recorded on the day of progesterone supplementation in FET cycles. In the combined analysis, endometrial thickness groups (group 1: equal or < 8 mm; group 2: >8 mm) were subdivided into 2 endometrial patterns (pattern A: triple-line; pattern B: no-triple line). Clinical pregnancy rate, spontaneous abortion rate, and live birth rate in different groups were analyzed.A total of 1512 cycles were reviewed. The results showed that significant differences in endometrial thickness and pattern were observed between the pregnant group (n = 1009) and no pregnant group (n = 503) (P < .05), while no significant differences were found between the live birth group (n = 844) and no live birth group (n = 668). Combined analysis revealed those with endometrial thickness > 8 mm and triple-line endometrial pattern had significant higher clinical pregnancy rates, while spontaneous abortion rates and live birth rates showed no significant differences among these subgroups.This study suggested neither individual nor combined analysis of endometrial thickness and pattern had predicting effects on live birth following IVF treatments, and embryo quality might be the one that really has effects.

Endometrial thickness as a predictor of the reproductive outcomes in fresh and frozen embryo transfer cycles: A retrospective cohort study of 1512 IVF cycles with morphologically good-quality blastocyst

To evaluate the relationship between endometrial thickness during fresh in vitro fertilization (IVF) cycles and the clinical outcomes of subsequent frozen embryo transfer (FET) cycles.FET cycles using at least one morphological good-quality blastocyst conducted between 2012 and 2013 at a university-based reproductive center were reviewed retrospectively. Endometrial ultrasonographic characteristics were recorded both on the oocyte retrieval day and on the day of progesterone supplementation in FET cycles. Clinical pregnancy rate, spontaneous abortion rate, and live birth rate were analyzed.One thousand five hundred twelve FET cycles was included. The results showed that significant difference in endometrial thickness on day of oocyte retrieval (P = .03) was observed between the live birth group (n = 844) and no live birth group (n = 668), while no significant difference in FET endometrial thickness was found (P = .261) between the live birth group and no live birth group. For endometrial thickness on oocyte retrieval day, clinical pregnancy rate ranged from 50.0% among patients with an endometrial thickness of ≤6 mm to 84.2% among patients with an endometrial thickness of >16 mm, with live birth rate from 33.3% to 63.2%. Multiple logistic regression analysis of factors related to live birth indicated endometrial thickness on oocyte retrieval day was associated with improved live birth rate (OR was 1.069, 95% CI: 1.011-1.130, P = .019), while FET endometrial thickness did not contribute significantly to pregnancy outcomes following FET cycles. The ROC curves revealed the cut-off points of endometrial thickness on oocyte retrieval day was 8.75 mm for live birth.Endometrial thickness during fresh IVF cycles was a better predictor of endometrial receptivity in subsequent FET cycles than FET cycle endometrial thickness. For those females with thin endometrium in fresh cycles, additional estradiol stimulation might be helpful for adequate endometrial development.

Elective frozen-thawed embryo transfer (FET) in women at risk for ovarian hyperstimulation syndrome

Elective cryopreservation of cultured embryos has become a treatment option for women at risk for ovarian hyperstimulation syndrome (OHSS). The aim of our study was to investigate the outcome of elective cryopreservation and consecutive frozen-thawed embryo transfer (FET) in a large IVF clinic in Austria. A total of 6104 controlled ovarian hyperstimulation cycles (COH) were performed on 2998 patients including 200 patients (6.7%) who were undergoing elective cryopreservation and FET due to high risk of OHSS. We estimated the cumulative live birth rate using the Kaplan-Meier method and evaluated independent predictors for successful live births with a Cox model. A total of 270 frozen-thawed embryo transfers were performed on 200 patients with up to 4 transfers per patient. The first embryo transfer showed a live birth rate of 42.0%, the second transfer showed a cumulative rate of 58.5%. After a total of 4 FETs from the same COH cycle, a cumulative live birth rate of 61.0% per COH cycle could be achieved. Four cases of OHSS occurred amongst these patients (2.0%), all of them of moderate severity. Multivariate analysis identified maternal age, the use of assisted hatching and the number of embryos transferred at the blastocyst stage as independent predictors for cumulative live birth. Our study clearly suggests that elective FET is safe and shows excellent cumulative live birth rates. This concept can, therefore, be used to avoid the severe adverse events caused by COH and the inefficient use of cultured embryos.

Blastocyst transfer is not associated with increased unfavorable obstetric and perinatal outcomes compared with cleavage-stage embryo transfer

BACKGROUND

Recent studies demonstrated controversial results of whether there are risks in fetal outcomes after blastocyst-stage embryos transfer (BT) compared with cleavage-stage embryos transfer (CT).

AIMS

To compare the implantation rates (IR), clinical pregnancy rates (cPR), birth rates (BR), gestational weeks, preterm birth rates, birth weights and low birth weight rates between CT and BT groups.

METHODS

A retrospective study of 1627 embryos transfer cycles was performed from May 2014 to April 2015. The cycles were divided into two groups according to transfer stage: CT on Day 3 (n = 798) and BT on Day 5 (n = 829). For the CT group, it must have surplus embryos and only surplus embryos developed to available blastocysts, the cleavage-stage embryos could be included. The clinical outcomes of two groups were analyzed.

RESULTS

The IR in CT group was lower than BT group (48.98% vs. 60.68%; p < 0.01). There were no significant differences in the clinical pregnancy rate and birth rate between BT and CT groups. For singletons and twin deliveries, there were no significant differences in gestational weeks, preterm birth rates, birth weights and low birth weight rates between two groups.

CONCLUSION

Blastocysts had higher implantation potential than cleavage-stage embryos. Extended embryo culture was not related to increased adverse obstetric and perinatal outcome.

Effect of normal sperm morphology rate (NSMR) on clinical outcomes for rescue-ICSI(R-ICSI) patients

PURPOSE

To investigate whether the normal sperm morphology rate (NSMR) can affect the clinical outcomes of rescue-ICSI(R-ICSI) patients.

METHODS

Based on different NSMR, the patients were divided into two groups as follows: NSMR < 4% and NSMR ≥ 4% group. Main outcomes compared were fertilization, cleavage, normal fertilization, high-quality embryo, transferrable embryo, no transferrable embryo cycles, implantation, clinical pregnancy and abortion rate. Some men's and women's basic parameters were compared between pregnancy and non-pregnancy group.

RESULTS

The basic parameter such as female age, endometrial thickness, infertility duration, Gn administration, Gn days, basal serum FSH and basal serum E2 found no significant difference between NSMR < 4% and NSMR ≥ 4% group (p > 0.05). There was no significant difference in aspects of the number of retrieved oocytes, the number of transferred embryos, fertilization, cleavage, normal fertilization, high-quality embryo, transferrable embryo, no transferred embryo cycle, implantation, clinical pregnancy and abortion rate between two groups (p > 0.05). Between pregnancy and non-pregnancy group, we observed no significant difference in the female age, the number of retrieved oocytes, the number of high-quality embryo, the number of transferrable embryos, Gn administration, Gn does, endometrial thickness, infertility duration, basal serum FSH, basal serum E2, sperm concentration and progressively motile sperm (p > 0.05).

CONCLUSIONS

Teratospermia made no effect on clinical outcomes of rescue-ICSI(R-ICSI) patients.

Prognostic factors for patients undergoing vitrified-warmed human embryo transfer cycles: a retrospective cohort study

We examined the prognostic factors for pregnancy in 210 vitrified-warmed embryo transfer (ET) cycles in 121 patients. The univariate analysis showed that age, gravida, the number of cycles associated with infertility caused by endometriosis, the number of previous assisted reproductive technology (ART) treatment cycles, and the number of ICSI procedures were significantly lower in pregnant cycles compared with non-pregnant cycles. The percentages of ET using at least one intact embryo and of ET using at least one embryo that had developed further after warming were significantly higher in pregnant cycles compared with non-pregnant cycles. Multivariate logistic regression analysis showed that previous ART treatment cycles, ET with at least one intact embryo, and ET using at least one embryo that had developed further were independent prognostic factors for pregnancy in vitrified-warmed ET cycles. We conclude that fewer previous ART treatment cycles, ET using at least one intact embryo, and ET with embryos that have developed further after warming might be favourable prognostic factors for pregnancy in vitrified-warmed ET cycles.

Effects of three pro-nuclei (3PN) proportion incidence on clinical outcomes of patients with lower retrieved oocytes in the fresh cleavage-stage embryo transfer (ET) cycles

PURPOSE

To analyze the three pro-nuclei (3PN) incidence on clinical outcomes of patients with lower retrieved oocytes in the fresh cleavage-stage embryo transfer (ET) cycles.

METHODS

This study included 1200 fresh cleavage-stage ET cycles from January 2013 to June 2015. The patients were divided into 3PN = 0% (773 cycles) and 3PN > 0% (427 cycles) group. Main outcomes compared were fertilization, cleavage, normal fertilization, good quality embryo, implantation, clinical pregnancy, and early abortion rate.

RESULTS

We observed that there was no significant difference in female's age, the number of retrieved oocytes, the number of transferred embryos, the number of good quality embryos, endometrial thickness, infertile time, basal serum follicle-stimulating hormone, and E2 value between two groups (p > 0.05). The fertilization (89.43 versus 83.90%, p < 0.001) and cleavage (98.34 versus 97.19%, p = 0.048) rates were significantly higher in 3PN > 0% than 3PN = 0% group. However, the normal fertilization (70.05 versus 50.67%, p < 0.001), good quality embryos (37.11 versus 26.47%, p < 0.001), and clinical pregnancy (49.81 versus 43.79%, p = 0.046) rates were significantly higher in 3PN = 0% than 3PN > 0% group. The implantation (35.88 versus 33.78%, p = 0.333) and early abortion (8.83 versus 10.70%, p = 0.474) rates were not significantly different between two groups.

CONCLUSION

3PN incidence might make a negative effect on clinical outcomes for patients with lower retrieved oocytes in the fresh cleavage-stage ET cycles.

Does the Presence of Blood in the Catheter or the Degree of Difficulty of Embryo Transfer Affect Live Birth?

The technique used for embryo transfer (ET) can affect implantation. Prior research that evaluated the effect of postprocedural blood of the transfer catheter tip have yielded mixed results, and it is unclear whether this is actually a marker of difficulty of the transfer. Our objective was to estimate the effect of blood at the time of ET and the difficulty of ET on live birth rates (LBR). This retrospective cohort study utilized generalized estimating equations (GEEs) with nesting for repeated cycles for all analyses. Univariate modeling was performed and a final multivariate (adjusted) GEE model accounted for all significant confounders. Embryo transfers were subjectively graded (easy, medium, or hard) by a physician at the time of transfer. The presence of blood at ET was associated with more difficult ETs, retained embryos, and presence of mucous in the catheter. In the univariate analysis, ET with blood was not associated with live birth, while the degree of difficulty for ET had a negative impact on LBR. In the final multivariate GEE model, which accounts for repeated cycles from a patient, the only factors associated with an increased LBR were the degree of difficulty of the ET, female age, and blastocyst transfer. After controlling for confounding variables, the presence of blood in the transfer catheter was not associated with the likelihood of pregnancy and thus was not an independent predictor of cycle outcome. This indicates that the difficulty of the transfer itself was a strong negative predictor of pregnancy.

Effect of embryo morphology and morphometrics on implantation of vitrified day 3 embryos after warming: a retrospective cohort study

BACKGROUND

Characteristics routinely used to evaluate embryo quality after thawing include number of blastomeres survived and presence of mitosis resumption after overnight culture. It is unknown to which extent symmetry and fragmentation affect implantation after warming and whether application of stricter criteria either before vitrification or after warming would improve implantation rate (IR) of vitrified/warmed embryos. This study aimed to find new parameters to improve selection criteria for vitrification and for transfer after warming.

METHODS

Firstly, we evaluated standard morphological characteristics (intact survival, mitosis resumption, number of blastomeres, symmetry and fragmentation) of 986 warmed day 3 embryos and, from a subset of 654, we evaluated morphometric characteristics (fragmentation, symmetry and volume change). Secondly, we tested the hypothesis that IR of day 3 vitrified/warmed embryos is influenced by morphometric characteristics. IR per embryo transferred was calculated using embryos that were transferred in a single embryo transfer (SET) or a double embryo transfer (DET) with either 0 or 100 % implantation (830/986). We investigated the significant differences in IR between the different categories of a specific characteristic. These categories were based on our standard embryo evaluation system. The statistical tests Chi-square, Fisher's exact or Cochrane-Armitage were used according to the type and/or categories of the variable.

RESULTS

The 986 embryos were transferred in 671 FET cycles with 16.9 % (167/986) IR. After exclusion of DET with 1 embryo implanted, IR per embryo transferred was 12.4 % (103/830). Embryo symmetry, fragmentation and volume change in vitrified/warmed day 3 embryos were not associated with IR. However, when mitosis resumption was present after overnight culture, intact embryos reached significantly higher IR than non-intact embryos and only when the embryo compacted after overnight culture the number of cells damaged after warming had no effect on IR. Concretely, embryos with 8 cells after warming or >9 cells after overnight culture-including compacted embryos-reached the highest IR (>15 %) while embryos with <6 cells after warming or with ≤6 cells after overnight culture had extremely low IR (<1 %).

CONCLUSIONS

IR of vitrified embryos is determined by the number of cells lost, by the occurrence of mitosis resumption, and by the specific number of blastomeres present but not by fragmentation, blastomere symmetry or volume change. Unselecting embryos for cryopreservation because of fragmentation >10 % and/or symmetry < 75 % only leads to unwanted loss of embryos with acceptable implantation potential.

TRIAL REGISTRATION

Retrospectively registered NCT02639715 .

Effect of normal sperm morphology rate (NSMR) on clinical outcomes and fertilization methods selection in the ultra-short-term GnRH-a protocol

PURPOSE

To investigate whether intracytoplasmic sperm injection (ICSI) can improve the clinical outcomes of the male patients with teratozoospermia in the ultra-short term GnRH-a protocol.

METHODS

Based on different normal sperm morphology rate (NSMR), the patients were divided into three groups as follows: NSMR = 0% group, 1% ≤NSMR <4% group and NSMR ≥4% group. Each group was compared with two fertilization type of in-vitro fertilization (IVF) and ICSI separately. Main outcomes compared were normal fertilization, high-quality embryo, transferrable embryo, implantation, pregnancy and abortion rate.

RESULTS

We observed that the total clinical pregnancy rate in single cleavage-stage embryo transfer (SET) group was significantly lower compared with double cleavage-stage embryo transfer (DET) group (23.87% versus 40.08%; p < 0.001). There was no significant difference in the aspects of female age, endometrial thickness, infertility duration and the number of retrieved oocytes among three groups (p > 0.05). The normal fertilization, high-quality embryo, transferrable embryo, implantation, pregnancy and abortion rate of IVF and ICSI showed no significant difference among three groups (p > 0.05).

CONCLUSION

ICSI cannot improve clinical outcomes of the patients with teratozoospermia in the ultra-short term GnRH-a protocol.

No adverse effects were identified on the perinatal outcomes after laser-assisted hatching treatment

The aim of this study was to evaluate the safety of laser-assisted hatching (LAH) by comparing obstetric and neonatal outcomes between assisted hatching and control groups in cryopreserved embryo transfer cycles. A retrospective cohort analysis was carried out. A total of 699 women with 392 infants delivered were included. Laser- assisted hatching was carried out on D-3 thawed and warmed embryos before transfer in 480 cryopreserved embryos transfer cycles. Obstetric outcomes, neonatal outcomes, and congenital birth defects were recorded. A total of 815 cryopreserved embryo transfer cycles (480 in LAH group and 335 in control group) in 699 patients were analysed. Statistically significantly higher implantation (31.85% versus 16.95%), clinical pregnancy (53.96% versus 33.43%) and live delivery (44.58% versus 23.88%) rates were observed in the LAH group (all P < 0.001). For either singleton or multiple gestations, no statistically significant differences were found in mean gestational age, mean birth weight and mean Apgar score. Four major malformations occurred in the assisted hatching group and three malformations (one major and two minor) in the control group. This study did not identify any harmful effect of LAH on neonates, which suggested that LAH may be a safe treatment in cryopreserved embryo transfer cycles.

Polymorphisms of VEGF and VEGF receptors are associated with the occurrence of ovarian hyperstimulation syndrome (OHSS)-a retrospective case-control study

BACKGROUND

Ovarian hyperstimulation syndrome (OHSS) is the most serious complication of IVF/ICSI therapy. The pathophysiology and etiology of the disease is still not fully clarified.

METHODS

To assess whether polymorphisms of the VEGF/VEGF-receptor system contribute to the occurrence of ovarian hyperstimulation syndrome (OHSS), we performed a retrospective analysis of 116 OHSS patients, and 124 female controls. The following SNPs were genotyped: Rs2071559 (VEGFR2-604); rs2305948 (VEGFR2-1192); rs1870377 (VEGFR2-1719); rs2010963 (VEGF-405); and rs111458691 (VEGFR1-519). Odds ratios (ORs) were estimated with a 95% confidence interval (CI). Linkage disequilibrium (LD) analysis was performed in the three loci of the VEGFR2 gene.

RESULT

We found an overrepresentation of the T allele of the VEGFR1-519 polymorphism in OHSS patients (P = 0.02, OR: 3.62, CI: 1.16 - 11.27). By genotype modeling, we found that polymorphism of VEGFR1-519 and VEGF-405 showed significant differences in patients and controls (p = 0.02, OR: 3.79 CI: 1.98 - 11.97 and p = 0.000005, OR: 0.29, CI: 0.17 - 0.50). LD analysis revealed significant linkage disequilibrium in VEGFR2.

CONCLUSION

Polymorphisms in the VEGFR2 gene and in the VEGF gene are associated with the occurrence of OHSS. This strengthens the evidence for an important role of the VEGF/VEGF- receptor system in the occurrence of OHSS.

The outcome of different post-thawed culture period in frozen-thawed embryo transfer cycle

PURPOSE

To study the influence of post-thawed culture (2-4 h and 20-24 h) on the outcome of frozen-thawed embryo transfer (FET) cycle.

METHODS

In this retrospective study, a total of 1,353 patients were undergoing the FET treatment at the reproductive medical center between June 2010 and July 2012. 3,398 frozen-thawed embryos were divided in two study groups, depending on their post-thawed culture period: short culture (2-4 h) group and long culture (20-24 h) group. Groups were compared including clinical pregnancy rate, implantation rate, spontaneous abortion rate, ectopic pregnancy rate, multiple pregnancy rate, live birth rate and birth weight.

RESULTS

When embryos including at least one grade I embryo after thawed transferred, the clinical pregnancy rate, implantation rate, multiple pregnancy rate, abortion rate, ectopic pregnancy rate, live birth rate and birth weight were similar in the short culture group compared with these in the long culture group.

CONCLUSIONS

The outcomes of the two approaches (short culture and long culture) are no different in FET cycles.