Autologous granulosa cell coculture demonstrates zygote suppression of granulosa cell steroidogenesis

Objective: To determine if embryos can modulate steroid hormone production by luteinized granulosa cells. Design: Granulosa cells obtained from follicular aspirates were cultured alone or in the presence of a two-pronuclear zygote. The production of E(2) and P by these cultures was evaluated by RIA. Setting: In Vitro Fertilization Unit in an academic research environment. Patients: Sixteen women undergoing IVF. Interventions: Standard IVF-ET treatment cycle using leuprolide acetate for pituitary desensitization before hMG or urofollitropin for ovarian stimulation. Main Outcome Measures: Estradiol and P concentration in culture media of luteinized granulosa cells alone or granulosa cells cocultured with a two-pronuclear embryo. Results: Both E(2) and P production by luteinized granulosa cells was reduced when cultured in the presence of an embryo. Conclusions: Human embryos secrete a factor that regulates granulosa cell steroidogenesis.