RESUMEN
AIM: The aim of the present study was to investigate the effects of long protocol ovulation induction on the ultrastructure of the human endometrial epithelium on days luteinizing hormone (LH) + 4 and LH+ 6 of the menstrual cycle. METHODS: Endometrial biopsies were obtained on days LH+ 4 (n = 9) and LH+ 6 (n = 10) from infertile women who were under standard long protocol with luteal phase supplementation with IM (intramuscular) progesterone, but where the embryo had not been formed or transferred, due to the male factor problem. Biopsies were also taken on days LH+ 4 (n = 5) and LH+ 6 (n = 5) from fertile women who had not received ovulation induction drugs as control groups. After preparation and taking light and electron micrographs from samples, qualitative and quantative evaluations (morphological and morphometric) were accomplished and the data was compared using the unpaired student t-test. RESULTS: Qualitative results showed the presence of the nuclear channel system, vacuoles of glycogen and giant mitochondria in all of the samples. Qualitative analysis showed that the volume fraction (Vv) of the euchromatin to the nucleus, the rough endoplasmic reticulum and the mitochondria to the cell, were not statistically different (P > 0.05) in samples taken on LH+ 4 in both control and test groups. The Vv of these features, however, to the cell in the test group was significantly (P < 0.05) higher than those in the control taken on LH+ 6. CONCLUSIONS: These results suggest that long protocol ovulation induction with luteal phase support with progesterone alter the normal development of the human endometrium in the mid luteal phase and could decrease the implantation success rate.