Objective: To compare the effectiveness of intramuscular (IM) and intravaginal (IV) progesterone for luteal phase support, in patients undergoing in vitro fertilization-embryo transfer cycles (IVF-ET).
Design: retrospective, observational, case-control study
Setting: Centro Natalità, San Raffaele Hospital, Milan, Italy, from July 2007 to June 2009.
Patient(s): 172 A-GnRH down-regulated IVF-ET cycles in patients with age < 40 years.
Intervention(s): Luteal phase support with IM progesterone (50 mg daily) or IV progesterone (90 mg daily).
Main outcome measure(s): Biochemical pregnancy, clinical pregnancy, miscarriage, ongoing pregnancy rates and patient's acceptability.
Results: IM progesterone conferred more benefit compared with IV progesterone in terms of ongoing pregnancy rate (24.4% vs 12.7%; P < 0.05).
Conclusions: In standard IVF cycles, our data showed that IM progesterone appears to be more effective at providing luteal support, thus rendering with IV progesterone.