Short versus extended progesterone supplementation for luteal phase support in fresh IVF cycles: a systematic review and meta-analysis

•Duration of luteal support for fresh IVF cycles is highly variable between centres.•Early cessation of progesterone does not significantly impact clinical outcomes.•Randomization of >4000 women with positive HCG would confirm non-inferiority. This review and meta-analysis aim to assess the effect of prolonged progesterone support on pregnancy outcomes in women undergoing fresh embryo transfer after IVF/intracytoplasmic sperm injection (ICSI). Two independent authors searched Embase, MEDLINE and grey literature from inception to January 2019 for randomized controlled trials (RCT) of prolonged progesterone support versus early cessation. Risk of bias was assessed. Outcome measures were live birth, miscarriage and ongoing pregnancy rate. The study was registered with PROSPERO (CRD42018088605). Seven trials involving 1627 participants were included: three reported live birth rate (672/830), seven the miscarriage rate (178/1627) and seven the ongoing pregnancy rate (1351/1627). Clinical outcomes were similar between early progesterone cessation versus progesterone continuation: live birth rate (risk ratio [RR] 0.94, 95% confidence interval [CI] 0.88–1.00), miscarriage rate (RR 0.91, 95% CI 0.69–1.20) and ongoing pregnancy rate (RR 0.98, 95% CI 0.91–1.05). Ongoing pregnancy rates were similar when analyses were restricted to those with cessation of progesterone on the day of a positive human chorionic gonadotrophin (RR 0.93, 95% CI 0.83–1.06). This meta-analysis suggests that prolonged progesterone support may be unnecessary after fresh embryo transfer. Further larger RCT would be useful to corroborate and lead to standardized duration of progesterone luteal phase support across IVF/ICSI centres.