Metformin, an oral biguanide administrated for treating type-2 diabetes mellitus, is a safe
and effective drug recently experimented also in patients with polycystic ovary syndrome
(PCOS). The administration of metformin induces ovulatory cycles in CC-resistant or
-nonresistant patients with PCOS, and improves the ovulation rate as an additional treatment
in women who received CC.
To date, it is unknown the best protocol for metformin administration. In particular, it is
not known how long patients who ovulate under metformin should continue treatment before
switching to second-line ovulation induction therapy. In this regard, in a recent study by
the Kaplan-Meier survival analysis we demonstrated that the first pregnancy occurred late
after metformin with an estimated median of seven months.
Based on these considerations, the aim of the present study will be to evaluate the clinical
efficacy of metformin according to its duration of administration in infertile PCOS patients
ovulating under treatment.