Danhof NA, et al. - Researchers evaluated whether follicle-stimulating hormone (FSH) or clomiphene citrate (CC) is the most effective stimulation regimen with regard to ongoing pregnancies in couples with unexplained subfertility undergoing IUI with adherence to strict cancellation criteria as a measure to reduce the number of multiple pregnancies. Findings indicated that adherence to strict cancellation criteria is a successful solution to reduce the number of multiple pregnancies in IUI.

Methods

• An open-label multicenter randomized superiority-controlled trial was conducted in the Netherlands.
• Couples diagnosed with unexplained subfertility and scheduled for a maximum of four cycles of IUI with ovarian stimulation with 75-IU FSH or 100-mg CC were randomized.
• In the event of > 3 follicles developed, cycles were cancelled.
• Cumulative ongoing pregnancy rate was assessed as the primary outcome.
• Secondary outcome included multiple pregnancy.
• Data were analyzed on intention-to-treat basis.
• Relative risks and absolute risk difference were calculated with 95% CI.

Results

• In this trial, 369 women were allocated to ovarian stimulation with FSH and 369 women to ovarian stimulation with CC between July 2013 and March 2016.
• Ovarian stimulation with FSH vs CC led to an ongoing pregnancy in 113 women (31%) vs 97 women (26%), respectively (RR=1.16, 95% CI: 0.93 to 1.47; ARD=0.04, 95% CI: -0.02 to 0.11).
• Multiple pregnancy was noted in 5 (1.4%) women following ovarian stimulation with FSH and 8 women (2.2%) following ovarian stimulation with CC (RR=0.63, 95% CI: 0.21 to 1.89; ARD=-0.01, 95% CI: -0.03 to 0.01).