Hormonal and histological evaluation of the luteal phase after combined GnRH-agonist/gonadotrophin treatment for superovulation and luteal phase support in in-vitro fertilization.

A hormonal and histological study of the luteal phase was performed in 21 stimulated in-vitro fertilization (IVF) patients not undergoing embryo transfer. Ovarian stimulation was carried out with gonadotrophins [follicle stimulating hormone (FSH) + human menopausal gonadotrophin (HMG)] under pituitary suppression with buserelin. Ovulation was induced with 5000 IU human chorionic gonadotrophin (HCG) and additional doses of 5000, 2500 and 2500 IU were given on the day of follicular aspiration, and 2 and 5 days later respectively, to support the luteal phase. Supraphysiological levels of oestradiol (E2) and progesterone in plasma were found in the midluteal phase of all women, while prolactin was in the normal range. An endometrial biopsy taken in the late luteal phase was normal in 90.5% (19/21) of patients, most of them (15/19, 79%) having E2 greater than 1500 pg/ml on the day of HCG. Conversely, both patients with defective endometrial biopsies had E2 levels less than 1500 pg/ml.