Effect of frozen/thawed embryo transfer on birthweight, macrosomia, and low birthweight rates in US singleton infants

Abstract STUDY QUESTION Is there an association between peak serum estradiol (E2) level during controlled ovarian stimulation (COS) and neonatal birthweight in freeze-all cycles? SUMMARY ANSWER Peak serum E2 level during ovarian stimulation is not associated with neonatal birthweight in freeze-all cycles. WHAT IS KNOWN ALREADY Supraphysiologic E2 levels during COS have been demonstrated to generate a suboptimal peri-implantation endometrial environment and thus lead to adverse neonatal outcomes in fresh embryo transfer cycles. Previous experimental studies also suggested a potential influence of superovulation on oocyte epigenetic programming, but whether it translates into altered phenotypes of fetal growth and development remains unclear in clinical practice. By segmenting the process of COS and embryo transfer, the freeze-all policy provides a novel model to investigate the sole impact of ovarian stimulation on oocytes after ruling out the effects of hyperestrogenic milieu on endometrium in fresh cycles. STUDY DESIGN, SIZE, DURATION A retrospective cohort study of 8501 patients who underwent their first COS cycles with a freeze-all strategy and delivered live-born singletons in subsequent frozen-thawed embryo transfer cycles from January 2007 to December 2016 at a tertiary-care academic medical center. PARTICIPANTS/MATERIALS, SETTING, METHODS Patients were categorized into six groups according to E2 level on trigger day in regular increments of 1000 pg/mL: <1000, 1000–1999, 2000–2999, 3000–3999, 4000–4999 and ≥5000 pg/mL. Univariable and multivariable linear regression and logistic regression analysis were performed to assess the independent association between peak E2 level and measures of neonatal birthweight including absolute birthweight, Z-score, low birthweight (LBW) and small-for-gestational age (SGA). MAIN RESULTS AND THE ROLE OF CHANCE The six groups did not differ significantly in birthweight, Z-score or the incidence of LBW and SGA. Compared with the E2 <1000 pg/mL group, the adjusted mean difference (95% confidence interval [CI]) of stratified higher E2 groups was 17.2 (−31.0–65.5), 12.3 (−35.9–60.5), −4.1 (−51.9–43.7), −0.6 (−48.9–47.8) and −3.6 (−50.0–42.8) g for birthweight, and 0 (−0.11–0.10), 0.02 (−0.08–0.12), 0.04 (−0.06–0.14), −0.01 (−0.11–0.10) and −0.04 (−0.14–0.06) for Z-score, respectively. Regarding the outcomes of LBW and SGA, no increased risks were observed in each E2 category, with the adjusted odds ratio (95% CI) being 1.21 (0.68–2.16), 1.0 (0.58–1.90), 0.90 (0.50–1.63), 0.93 (0.51–1.69) and 1.08 (0.61–1.90) for LBW, and 0.97 (0.58–1.64), 1.06 (0.63–1.77), 0.77 (0.46–1.31), 0.71 (0.41–1.22) and 1.00 (0.60–1.65) for SGA, respectively. LIMITATIONS, REASONS FOR CAUTION The study was retrospective in design, and other unknown confounding factors may not be included for adjustment. Furthermore, the generalization of the study finding could be limited to some extent by the majority of double cleavage-stage embryo transfer and difference in birthweight reference percentiles between Chinese and other populations. WIDER IMPLICATIONS OF THE FINDINGS Our observations suggest that the hyperestrogenic milieu during COS does not seem to pose adverse effects on neonatal birthweight after frozen-thawed embryo transfer, which provides reassuring information for high ovarian responders in freeze-all cycles concerning their offspring’s health. STUDY FUNDING/COMPETING INTEREST(S) This study was funded by the National Key Research and Development Program of China (SQ2018YFC100163) and National Natural Science Foundation of China (81571397, 81771533). The authors declare no conflict of interest.

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Increased Risk of High Birthweight in Singleton Newborns after Frozen-Thawed Embryo Transfer According to Endometrial Preparation, Ovulatory or Artificial Cycle

10.20944/preprints202101.0510.v1 ◽

2021 ◽

Author(s):

Sylvie Epelboin ◽

Julie Labrosse ◽

Emmanuel Devouche ◽

Solenne Gricourt ◽

Dominique Luton ◽

...

Keyword(s):

Embryo Transfer ◽

Low Birthweight ◽

Primary Objective ◽

Ovulatory Cycle ◽

Future Health ◽

Endometrial Preparation ◽

Increased Risk ◽

Frozen Thawed Embryo Transfer ◽

Artificial Cycle ◽

Thawed Embryo Transfer

Background: It is unknown whether prolonged artificial hormonal environment during early fetal development affects the birthweight of singletons born after frozen-thawed embryo transfer (FET). Methods: A retrospective observational study included singleton births>22 weeks of gestation obtained after FET between 2013-2019 after endometrial preparation with ovulatory cycle (OC) or artificial cycle (AC). Our primary objective was to compare birthweight of singletons after FET between endometrial preparation by OC or AC. Secondary objectives included prolonged pregnancies, high birthweight, low birthweight, SGA and LGA rates. Multivariate analyses were performed considering potential confounding factors. Results: Among 198 singleton live births after FET, 112 were obtained with OC and 86 with AC. Prolonged pregnancies rate was higher in AC (25.6% vs. 7.1%, respectively, p=0.001). Mean birthweight was higher (+219g) in AC (3386g vs. 3167g, p=0.01; adjusted-p=0.052), as well as the rate of babies exceeding 4000g (16.3% vs. 2.7%, p=0.03, adjusted-p=0.015). The rate of babies <2500g was lower in AC (3.5% vs. 11.6%, respectively, p=0.050, adjusted-p=0.049). Conclusions: Since OC does not strain the chances of pregnancy and in the incomplete knowledge of the consequences of neonatal overweight on the future health of children, OC preparation could be advocated as first-line endometrial preparation in FET.

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Comparison of birthweights in patients randomly assigned to fresh or frozen-thawed embryo transfer

10.26226/morressier.573c1513d462b80296c98a23 ◽

2016 ◽

Author(s):

Bruce Shapiro

Keyword(s):

Embryo Transfer ◽

Frozen Thawed Embryo Transfer ◽

Thawed Embryo Transfer

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THE EFFECT OF ASSISTED HATCHING IN FROZEN-THAWED EMBRYO TRANSFER CYCLES

Journal of Medicine and Pharmacy ◽

10.34071/jmp.2016.3.12 ◽

2016 ◽

pp. 80-84

Author(s):

Thi Tam An Nguyen ◽

Minh Tam Le ◽

Ngoc Thanh Cao

Keyword(s):

Embryo Transfer ◽

Zona Pellucida ◽

Assisted Hatching ◽

Implantation Failure ◽

Multiple Pregnancies ◽

Recurrent Implantation Failure ◽

Key Words Laser ◽

Implantation And Pregnancy Rates ◽

Frozen Thawed Embryo Transfer ◽

Thawed Embryo Transfer

Background: Laser assisted hatching technique based on the hypothesis to make an artificial hole on zona pellucida (ZP) that can help embryo hatching out of ZP easily. This technique has been shown to increase implantation and pregnancy rates in women of advanced age, in women with recurrent implantation failure and following the transfer of frozen–thawed embryos. This study described the outcome of frozen–thawed embryo transfers with laser assisted hatching (LAH), which is one of the safest method in nowadays. Purpose: To assess the effect of assisted hatching technique on the clinical outcomes in vitrified-warmed transfer cycles. Method: A total of 65 thawed-transfer cycles with 153 thawed-embryos undertaken within a 12-month period were analysed, Assisted hatching with laser zona thinning was performed with one-quarter of the zona pellucida circumference. The overall thawed-embryos (day 3) were kept in culture overnight. Patient were prepared the suitable endometrium and transferred embryos advantageously. Results: In which, having the rate of survival embryos were 143 occupying 94.3%, the percentage of grade 1 and 2 embryos occupied 55.9% and 29,3% respectively, and that were enrolled LAH before transfering of frozen–thawed embryos. The average transferred embryos were 2.4±0.8, The rate of implantation per transferred embryos and per transferred embryos cycles was 19.5% and 43.1% respectively. The rate of clinical pregnancies per embryo transfer cycles occupied 33.8% with percentage of early miscarriages (biochemical pregnancies and early clinical miscarriages) was 12.3%. The rate of ongoing pregnancies was 30.8% and multiple pregnancies was low just 12.3%. This result was equal or higher than other researchs in embryos transfer had or no LAH. Conclusion: LAH contributed to stable frozen–thawed embryos transfer effectiveness. Key words: Laser assisted hatching, frozen–thawed embryos transfer, zona pellucida (ZP)

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