Nuclear maturity and oocyte morphology after stimulation with highly purified follicle stimulating hormone compared to human menopausal gonadotrophin.

Several studies have shown that high concentrations of luteinizing hormone (LH) in the follicular phase of stimulation can have a negative effect on oocyte quality, pregnancy rate and incidence of miscarriage. The aim of the present study was to examine the effects of highly purified follicle stimulating/hormone (FSH HP) on ovarian stimulation and particularly on nuclear maturity and morphological appearance of the oocyte in intracytoplasmic sperm injection (ICSI) therapy and to compare the results with human menopausal gonadotrophin (HMG) stimulation. For this purpose, 50 patients for ICSI (HMG: 30; FSH HP: 20) and 26 patients for in-vitro fertilization (IVF; HMG: 14, FSH HP: 12) were stimulated with either HMG or FSH HP using a short-term protocol. Patients were divided into the two groups according to the first letter of their family name. No differences were observed among the groups in relation to patient age, duration of stimulation, number of aspirated oocytes or maturity of the oocyte-cumulus complex. After removal of the cumulus-corona cells in the ICSI oocytes, a significantly higher proportion of oocytes in the FSH HP group were nuclear mature (metaphase II) than in the HMG group (FSH HP: 88.8%, HMG: 80.6%; P = 0.009). Furthermore, in the FSH HP group, significantly fewer oocytes with dark cytoplasm were observed (FSH HP: 14.4%, HMG: 22.4%; P = 0.02). Fertilization, cleavage and pregnancy rates (FSH HP 38%, HMG: 34% per retrieval) were comparable in both groups. Based on the results obtained, it can be concluded that the short-term FSH HP treatment protocol synchronizes oocyte maturation better than comparable stimulation with HMG.