Differences in Ectopic Pregnancy Rates between Fresh and Frozen Embryo Transfer after In Vitro Fertilization: A Large Retrospective Study

Risk factors of ectopic pregnancy after in vitro fertilization-embryo transfer in Chinese population: A meta-analysis

BACKGROUND

The prevalence of ectopic pregnancy after assisted reproduction is notably high, posing a significant threat to the life safety of pregnant women. Discrepancies in published results and the lack of a comprehensive description of all risk factors have led to ongoing uncertainties concerning ectopic pregnancy after assisted reproduction.

OBJECTIVE

This study aimed to understand the risk factors for ectopic pregnancy after in vitro fertilization-embryo transfer in the Chinese population and provide a reference for targeted prevention and treatment.

METHODS

A comprehensive search of the China National Knowledge Infrastructure, Wang fang Database, China Science Technology Journal Database, Chinese Biomedical Literature Database, PubMed, Web of Science, and Embase was conducted to identify relevant literature on the risk factors for ectopic pregnancy in Chinese women after assisted reproductive technology in Chinese women. A meta-analysis of the included studies was performed using Stata17.

RESULTS

Overall, 34 articles were included in the analysis. The risk factors for ectopic pregnancy after in vitro fertilization-embryo transfer in the Chinese population included a thin endometrium on the day of HCG administration and embryo transplantation, a history of ectopic pregnancy, secondary infertility, a history of induced abortion, polycystic ovary syndrome, decreased ovarian reserve, tubal factor infertility, cleavage stage embryo transfer, fresh embryo transfer, artificial cycle protocols, elevated estradiol levels on the day of human chorionic gonadotropin administration, a history of tubal surgery, two or more number of embryo transfers, previous pregnancy history, and a history of pelvic surgery.

CONCLUSION

This study clarified the factors influencing ectopic pregnancy after in vitro fertilization and embryo transfer in the Chinese population, focusing on high-risk groups. Targeted and personalized intervention measures should be adopted to prevent and detect the disease early to reduce its incidence and harm.

TRIAL REGISTRATION

The protocol for this view was registered in PROSPERO (CRD42023414710).

Pregnancy Outcomes of Freeze-All versus Fresh Embryo Transfer in Women with Adenomyosis: A Retrospective Study

Adenomyosis has been associated with adverse fertility and pregnancy outcomes, and its impact on the outcomes of in vitro fertilization (IVF) has received much attention. It is controversial whether the freeze-all strategy is better than fresh embryo transfer (ET) in women with adenomyosis. Women with adenomyosis were enrolled in this retrospective study from January 2018 to December 2021 and were divided into two groups: freeze-all (n = 98) and fresh ET (n = 91). Data analysis showed that freeze-all ET was associated with a lower rate of premature rupture of membranes (PROM) compared with fresh ET (1.0% vs. 6.6%, p = 0.042; adjusted OR 0.17 (0.01-2.50), p = 0.194). Freeze-all ET also had a lower risk of low birth weight compared with fresh ET (1.1% vs. 7.0%, p = 0.049; adjusted OR 0.54 (0.04-7.47), p = 0.642). There was a nonsignificant trend toward a lower miscarriage rate in freeze-all ET (8.9% vs. 11.6%; p = 0.549). The live birth rate was comparable in the two groups (19.1% vs. 27.1%; p = 0.212). The freeze-all ET strategy does not improve pregnancy outcomes for all patients with adenomyosis and may be more appropriate for certain patients. Further large-scale prospective studies are needed to confirm this result.