Experimental evidence has shown that mice lacking the oestrogen receptor (ESR) gene are infertile with cystic ovaries and follicular arrest. In humans, several polymorphisms and mutations in the ESR gene have been identified. In this study we have analysed a common PvuII and a rare BstUI polymorphism in the ESR gene. Analysis was carried out on DNA samples from women undergoing ovarian stimulation for in-vitro fertilization (IVF) and embryo transfer and controls having at least one pregnancy. Comparisons were done between the three PvuII genotypes, concerning the mean numbers of follicles and oocytes and the mean ratios of follicles to oocytes harvested in two consecutive cycles. Significantly lower ratios were identified in the group lacking the PvuII polymorphism, compared with the groups with heterozygous or homozygous PvuII polymorphisms (P > 0.05 and P > 0.01 respectively). The rare haplotype having both PvuII and BstUI restriction sites on one chromosome was present only in the IVF group. Pregnancies from IVF were significantly rarer in patients who were homozygous for the PvuII polymorphism (P > 0.05). Our results suggest that genetic variability in the ESR has a role in the quality of the ovarian follicles as judged by the ovarian response to stimulation and may also affect implantation.

Misoprostol prior to hysteroscopy appears to facilitate an easier and uncomplicated procedure only in premenopausal women.

Ghrelin, apart from its metabolic role, is nowadays considered as a basic regulator of reproductive functions of mammals, acting at central and gonadal levels. Here, we investigated for possible direct actions of ghrelin on in vitro maturation of bovine oocytes and for its effects on blastocyst yield and quality. In experiment 1, cumulus oocyte complexes (COCs) were matured in the presence of four different concentrations of ghrelin (0, 200, 800 and 2000 pg/ml). In vitro fertilization and embryo culture were carried out in the absence of ghrelin, and blastocyst formation rates were examined on days 7, 8 and 9. In experiment 2, only the 800 pg/ml dose of ghrelin was used. Four groups of COCs were matured for 18 or 24 h (C18, Ghr18, C24 and Ghr24), and subsequently, they were examined for oocyte nuclear maturation and cumulus layer expansion; blastocysts were produced as in experiment 1. The relative mRNA abundance of various genes related to metabolism, oxidation, developmental competence and apoptosis was examined in snap-frozen cumulus cells, oocytes and day-7 blastocysts. In experiment 1, ghrelin significantly suppressed blastocyst formation rates. In experiment 2, more ghrelin-treated oocytes matured for 18 h reached MII compared with controls, while no difference was observed when maturation lasted for 24 h. At 18 and 24 h, the cumulus layer was more expanded in ghrelin-treated COCs than in the controls. The blastocyst formation rate was higher in Ghr18 (27.7 ± 2.4%) compared with Ghr24 (17.5 ± 2.4%). Differences were detected in various genes' expression, indicating that in the presence of ghrelin, incubation of COCs for 24 h caused over-maturation (induced ageing) of oocytes, but formed blastocysts had a higher hatching rate compared with the controls. We infer that ghrelin exerts a specific and direct role on the oocyte, accelerating its maturational process.

Oestradiol enhances pituitary sensitivity to gonadotrophin-releasing hormone (GnRH) in normal women, while in women undergoing ovulation induction the putative factor gonadotrophin surge attenuating factor (GnSAF) attenuates the response of luteinizing hormone (LH) to GnRH. To study the relationships between oestradiol and GnSAF during ovulation induction, 15 normally ovulating women were investigated in an untreated spontaneous cycle (control, first cycle), in a cycle treated with daily i.m. injections of 225 IU urinary follicle-stimulating hormone (FSH) (Metrodin HP, uFSH cycle) and in a cycle treated with daily s.c. injections of 225 IU recombinant FSH (Gonal-F, rFSH cycle). Treatment with FSH started on cycle day 2. The women during the second and third cycle were allocated to the two treatments in an alternate way. One woman who became pregnant during the first treatment cycle (rFSH) was excluded from the study. In all cycles, an i.v. injection of 10 microg GnRH was given to the women (n = 14) daily from days 2-7 as well as from the day on which the leading follicle was 14 mm in diameter (day V) until mid-cycle (n = 7). The response of LH to GnRH at 30 min (deltaLH), representing pituitary sensitivity, was calculated. In the spontaneous (control) cycles, deltaLH values increased significantly only during the late follicular phase, i.e. from day V to mid-cycle, at which time they were correlated significantly with serum oestradiol values (r = 0.554, P < 0.01). Initially during the early follicular phase in the uFSH and the rFSH cycles, deltaLH values showed a significant decline which was not related to oestradiol (increased GnSAF bioactivity). Then, deltaLH values increased significantly on cycle day 7 and further on day v with no change thereafter up to mid-cycle. On these two days, deltaLH values were correlated significantly with serum oestradiol values (r = 0.587 and r = 0.652 respectively, P < 0.05). During the pre-ovulatory period, deltaLH values in the FSH cycles were significantly lower than in the spontaneous cycles. Significantly higher serum FSH values were achieved during treatment with uFSH than rFSH. However, serum values of oestradiol, immunoreactive inhibin, and deltaLH as well as the number of follicles > or = 12 mm in diameter did not differ significantly between the two FSH preparations. These results suggest that in women undergoing ovulation induction with FSH, oestradiol enhances pituitary sensitivity to GnRH, while GnSAF exerts antagonistic effects. The rFSH used in this study (Gonal-F) was at least as effective as the uFSH preparation (Metrodin-HP) in inducing multiple follicular maturation in normally cycling women.

To study the role of oestradiol and progesterone in the secretion of leptin, 21 normally ovulating women were recruited from those scheduled for ovariectomy plus hysterectomy performed in mid-follicular phase of the cycle. Seven of the women were used as controls and received no hormonal treatment post-operatively. Another seven women received oestradiol (oestradiol group) and the remaining seven women received oestradiol plus progesterone (oestradiol plus progesterone group). Serum leptin values showed a temporal but significant increase 24 h after the operation and were significantly correlated with the cortisol and progesterone values, which increased temporarily at 12 h. At that time a marked decline in oestradiol concentrations was seen. After the temporal increase, leptin values in the controls and the oestradiol group decreased significantly up to day 4 (P: < 0.05), while in the oestradiol plus progesterone group they increased (P: < 0.01) and were significantly higher than in the other two groups (P: < 0.05). Body mass index (BMI) was the most important variable accounting for the changes in leptin values post-operatively, but in the oestradiol plus progesterone group progesterone correlated significantly with leptin independently of BMI. These results suggest that progesterone and cortisol can stimulate leptin secretion in women regardless of oestradiol concentrations.