Luteal phase support after mild ovulation induction with intrauterine insemination: an on-going debate

To evaluate the effect of luteal phase support (LPS) using progesterone vaginal gel on pregnancy rate (PR) and live birth rate (LBR) during cycles in which controlled ovarian stimulation (COH) was performed using gonadotropins with intrauterine insemination (IUI) cycles in patients with unexplained infertility and polycystic ovarian syndrome.

From 2010 to 2015, all IUI cycles in which COH was performed using gonadotropins were evaluated retrospectively. LPS was not used until July 2013, after which vaginal progesterone gel was applied in the luteal phase of IUI cycles. Both groups of patients were evaluated in terms of the effect of LPS on PR and LBR.

In total, 1578 IUI cycles were evaluated, of which 481 were LPS (+) and 1097 LPS (-). PR and LBR per cycle were 10.6% and 7.4%, respectively, in the LPS (+) group, and 11.6% and 7.7%, respectively, in the LPS (-) group (p = 0.31 and p = 0.25). PR and LBR per patient were 17% and 12%, respectively, in the LPS (+) group, and 17.4% and 12.3%, respectively, in the LPS (-) group (p = 0.48 and p = 0.82).

We found no difference in PR and LBR per cycle and per patient according to the use of LPS in IUI cycles in which COH was performed using gonadotropins. Thus, routine use of LPS in gonadotropin-stimulated cycles requires further research involving larger numbers of patients.