Donated-embryo Pregnancies Are Associated with Increased Risk of Hypertensive Disorders Even for Young Recipients: a Retrospective Matched-Cohort Study.

Objective: To determine whether pregnancies with donated embryos are at a higher risk of complications than the pregnancies from autologous frozen-thawed embryo transfer (FET).Design: Anonymous, multicenter, comparative, observational, retrospective, matched-cohort study.Setting: Six French assisted reproductive technique centers from 2003 to 2018.Patient(s): Seventy-three singleton pregnancies with donated embryos (exposed) and 136 singleton pregnancies after autologous FET (nonexposed) were matched at 7-8 weeks of gestation (pregnancy date, parity, and women's age) (2:1 ratio, respectively). In accordance with French practices, all women were <44 years old and donated embryos were discarded frozen embryos from other couples. Intervention(s): Not applicable.Main Outcome Measure(s): Percentages of hypertensive disorders of pregnancy (HDPs) with donated embryos versus autologous FET.Result(s): Groups were comparable (mean age: 34.5 years) and HDPs (24.6% vs. 11.9%) were significantly more frequent among the donated-embryo pregnancies, mostly in its severe forms (17.5% vs. 4.6%). In contrast, their respective isolated hypertension frequencies were comparable (7.0% vs. 7.3%). Multivariate analysis retained increased severe HDP risk with donated embryos (odds ratio 2.08 [95% confidence interval: 1.08-4.02]). No significant effect of endometrial preparation was observed. C-sections were more frequent for donated-embryo pregnancies (47.3% vs. 29.2%). Newborns from embryo donation or autologous FET were comparable for prematurity, birth weight and length, Apgar score, small for gestational age, large for gestational age, neonatal malformations, and sex ratio.Conclusion(s): Even for young women, the risk of severe HDP was 4 times higher for donated-embryo pregnancies than for autologous-FET pregnancies. The HDP risk must be acknowledged to inform donated-embryo recipients and provide careful pregnancy monitoring. (Fertil Steril (R) 2023;119:69-77. (c) 2022 by American Society for Reproductive Medicine.)