The objective of the study was to compare the live birth rate and miscarriage rate after fresh embryo transfer (Fresh ET) when patients are treated either with oral dydrogesterone or micronized vaginal progesterone (MVP) as luteal phase support (LPS). The vaginal route is still preferred, despite the discomfort for the patients and recent RCTs showing similar results for dydrogesterone and MVP.All 556 consecutive Fresh ET after autologous IVF procedure, from December 2011 to March 2013 in one centre in France were included. Patients were treated either with dydrogesterone 10mg every 12hours (n=267) or MVP 200mg every 12hours (n=289), the physician's arbitrary choice on the day of the oocyte aspiration procedure.The groups were comparable regarding the demographic data and stimulation protocols, except for the rank of the oocyte pickup procedure [1.54±0.80 vs. 1.74±0.96, (P=0.01)], with no significant difference in live birth rates (22.4% vs. 23.8%, P=0.77) and miscarriage rates (4.1% vs. 5.5%, P=0.55) for dydrogesterone vs. MVP respectively. The results were similar in a good prognosis patients' subgroup.LPS with either dydrogesterone or MVP after Fresh ET showed similar live birth rates and miscarriage rates. The benefits of the oral over vaginal route might be higher tolerance and possibly better compliance. Dydrogesterone seems to be a safe treatment, but its long-term innocuity needs to be further proven.
