High concentration of first-measured HCG after embryo transfer is associated with subsequent development of pre-eclampsia

Research question: Are outlier high values of first-measured human chorionic gonadotrophin (HCG) following embryo transfer related to pregnancy complications, specifically pre-eclampsia?Design: This retrospective cohort study screened 3448 women aged 18-45 years who underwent IVF between 2014 and 2019 and evaluated 614 women who had an intrauterine pregnancy following single embryo transfer (SET), 423 of whom had a live birth. Pregnancy and birth outcome information was available for final analysis in 280 cases. The setting was a university-based IVF centre. HCG was measured at a standardized time after the embryo transfer and the values correlated with adverse pregnancy outcomes associated with poor placentation.Results: Women with first-measured HCG in the highest quintile had a higher incidence of pre-eclampsia than those with lower HCG concentrations (odds ratio [OR] 4.08, 95% confidence interval [CI] 1.41-11.8 2) even after controlling for age, body mass index, parity and type of embryo transfer. Additionally controlling for embryo stage at embryo transfer did not change the results (OR 3.97, 95% CI 1.37-11.4 6). No differences were found in the incidence of fetal growth restriction.Conclusions: This is the first known report that links high first-measured HCG after SET to an adverse pregnancy outcome. If confirmed by future studies, initiation of preventive interventions at a very early stage of pregnancy merits further evaluation in this cohort of patients.

Automated summary

This retrospective cohort study investigates the relationship between outlier high values of HCG following embryo transfer and pregnancy complications, specifically pre-eclampsia. The study finds that women with the highest HCG concentrations have a lower incidence of pre-eclampsia. This is the first known report linking high first-measured HCG after SET to an adverse pregnancy outcome.