Metformin in the treatment of clomiphene citrate-resistant women with polycystic ovary syndrome undergoing in vitro fertilisation treatment: A randomised controlled trial

This study was conducted to determine the efficacy of metformin vs placebo in women with polycystic ovary syndrome (PCOS) undergoing IVF treatment. A total of 66 CC-resistant patients were studied prospectively. The women were randomly assigned to receive 850mg of metformin (n=34) or placebo (n=32) twice daily that started 1 month before commencing the IVF treatment and continued to the day of the pregnancy test. Compared with the metformin-treated group, women who received a placebo had a significant increase in terms of days of stimulation with HMG, number of HMG ampoules, number of follicles 14mm, number of oocytes retrieved, number of mature eggs, fertilisation rate and oestradiol level on the day of hCG administration. Similarly, women in the placebo group showed a significant increase in poor quality embryos, cancellation rate and the rate of ovarian hyperstimulation syndrome, as compared with the metformin-treated group. On the other hand, women who received metformin showed a significantly higher number of good quality embryos and implantation rate when compared with the placebo controls. Despite the transfer of a similar number of embryos, an insignificant increased in the pregnancy rate along with significant reduction in the abortion rate was observed in the metformin-treated group as compared with the placebo controls. No fetal abnormalities were encountered in the babies born in the metformin-treated group. It is concluded that metformin affects positively the quality of both oocytes and embryos without a significant increase in the pregnancy rate. It decreases significantly the rates of abortion and ovarian hyperstimulation syndrome.