Exploratory cohort study into underlying mechanism of differences in estrogen metabolism between Asian and Caucasian women during assisted reproductive technology treatment

Amy Kaing; Amanda Adeleye; Bani Tamraz; Victor Y Fujimoto

doi:10.1016/j.xfre.2023.10.002

Exploratory cohort study into underlying mechanism of differences in estrogen metabolism between Asian and Caucasian women during assisted reproductive technology treatment

F S Rep. 2023 Oct 13;4(4):396-401. doi: 10.1016/j.xfre.2023.10.002. eCollection 2023 Dec.

Authors

Amy Kaing¹, Amanda Adeleye², Bani Tamraz³, Victor Y Fujimoto¹

Affiliations

¹ Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, California.
² Section of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Chicago, Chicago, Illinois.
³ Department of Clinical Pharmacy, University of California, San Francisco, San Francisco, California.

Abstract

Objective: Explore whether racial differences in prevalence of CYP1A2∗1F polymorphism underlies estrogen metabolism differences among Asians and Caucasians.

Design: Prospective cohort study.

Setting: University-based fertility practice.

Patients: Asian or Caucasian patients who underwent ovarian stimulation (OS) or programmed cycle frozen embryo transfer (FET) between October 2019 and April 2021.

Interventions: None.

Main outcome measures: Trigger-day serum E2 per oocyte retrieved in OS cycles, and E2 on day of lining check in FET cycles.

Results: Seventy-one participants were enrolled, 55 in OS group (29 Caucasian and 26 Asian) and 16 in FET group (10 Caucasian and 6 Asian). Peak E2 per oocyte retrieved in the OS group (n = 48) differed by race, with significantly lower levels in Caucasians compared with Asians (177.5 ± 64.2 vs. 261.1 ± 139.5 pg/mL). Prevalence of CYP1A2∗1F polymorphism did not significantly differ by race. Compared using Kruskal-Wallis test, peak E2 per oocyte retrieved did not differ by CYP1A2∗1F genotype. In multivariate linear regression model, adjusting for body mass index, caffeine intake, and self-reported race, there remained no significant correlation. In FET group, serum E2 on day of lining check was also not significantly different by CYP1A2∗1F genotype.

Conclusions: Although a consistent difference in serum E2 between Asians and Caucasians undergoing OS was noted, the CYP1A2∗1F polymorphism is unlikely the primary driver of this difference.

Keywords: Assisted reproductive technologies; CYP1A2∗1F; estrogen metabolism; racial disparity.