Association of oestrogen receptor gene polymorphisms with outcome of ovarian stimulation in patients undergoing IVF

Oestrogen plays an important role in follicular formation and oocyte matura tion via its receptor (ER). Many studies have shown association of the ER g ene polymorphisms with a variety of pathological conditions. In this study we have examined the relationship of a common PvuII and a rare BstUI polymo rphism in the ER gene to the mean numbers of follicles and oocytes, their m ean ratios, mean number of embryos, mean oestrogen concentrations, mean siz e of the follicles and pregnancy rates. Analyses were carried out in 200 lo cal Chinese patients undergoing in-vitro fertilization (IVF) and embryo tra nsfer in three consecutive cycles. The mean follicular number, oocyte numbe r, embryo number, follicular size and pregnancy rate were significantly sma ller in patients homozygous for PvuII polymorphism (P < 0.001). These resul ts indicate that PvuII polymorphism may be associated with ovarian follicul ar development and subsequently with the pregnancy rate. This study support s the view that genetic variability in the ER gene may have a role in the q uality of the ovarian follicles in stimulation, which may affect implantati on. However BstUI polymorphism was not found in either the IVF or control g roups, suggesting that it has no role in the local Chinese population.