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Updated: Jun 23, 2026
Generation of Multicellular Human Primary Endometrial Organoids
Published on: October 4, 2019
Production of human chorionic gonadotropin during the normal menstrual cycle
Laurence A Cole1, Jovanna M Gutierrez
1USA hCG Reference Service, Department of Obstetrics and Gynecology, University of New Mexico, Albuquerque, NM 87131, USA. larry@hcglab.com
Objective:
To present a comprehensive study of pituitary human chorionic gonadotropin (hCG) production during the menstrual cycle, investigating its occurrence, timing and the possibility of a separate biologic role for pituitary hCG during the normal menstrual cycle.
Study Design:
Daily urine samples were tested from 185 women during 405 normal menstrual cycles. Levels of hCG and luteinizing hormone (LH) were measured daily.
Results:
hCG levels were detected at LH peak in 84% of menstrual cycles. At this time, hCG levels paralleled LH values. The remaining menstrual cycles (16%) had significantly lower LH levels, suggesting lack of detection of hCG as a result of low concentration of LH or very dilute urines. We infer that hCG is produced in all menstrual cycles.
Conclusion:
hCG is seemingly produced alongside LH in all menstrual cycles. hCG has a much greater circulating half-life compared to LH. It may function to extend the short, sharp LH peak in promoting ovulation or in promoting initial progesterone production by the corpus luteal cells.
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