By RRM Academy Reviewed by Dr. Naomi Whittaker, MD, Board-Certified OBGYN, MIGS, NFPMC, FCI Updated June 17, 2026

Chorionic Gonadotropin is a glycoprotein hormone the syncytiotrophoblast cells of the developing embryo and placenta produce, beginning shortly after implantation. Its beta-subunit (beta-hCG) is the molecular basis of all clinical pregnancy tests.

hCG serves three primary biological roles. First, it rescues the corpus luteum from regression, a process called luteal rescue: hCG binds LH/hCG receptors on luteal cells to sustain progesterone production through the first trimester, until placental progesterone synthesis is established at roughly 8 to 10 weeks of gestation. Second, it contributes to immune tolerance at the fetal-maternal interface. Third, it stimulates fetal testosterone production.

In NaProTECHNOLOGY practice, RRM clinicians may use exogenous hCG as an ovulation trigger in monitored cycles when appropriate follicular maturity is confirmed, supporting cycle-timed conception without bypassing the body's own ovulatory physiology.

This content is for educational purposes only and does not constitute medical advice. Consult an RRM clinician or healthcare provider for guidance specific to your situation.