Evaluation of Nifedipine Administration on Embryo Transfer Success Rate: a Randomized Clinical Trial

Background and Objective: In- vitro fertilization (IVF) is one of the approved treatment options for infertility. Despite many progresses in this field, its success rate is about 20 -25%. Utilization of drugs which suppress or decrease uterine smooth muscle contraction before embryo transfer, theoretically can improve fertility by increasing implantation rate. This study was designed to evaluate nifedipine administration on embryo transfer success. Materials and Methods: In this double blinded randomized clinical trial, ninety-eight infertile women from primary and secondary causes were included in two groups; one group received placebo and the other group a  single dose of 20 mg nifedipine, both thirty minutes before embryo transfer. Primary outcome was defined as clinical pregnancy, and secondary outcomes as live birth, ectopic pregnancy, multiple gestation and abortion. Results: Clinical pregnancy occurred in eighteen patients in the placebo group and in seventeen patients in nifedipine group (OR = 0.91, 0.40-2.09 (95% CI)). Sixteen patients in placebo group and fourteen patients in nifedipine group had successful live births (OR = 0.82, 0.34-1.95 (95% CI)). Multiple gestation (OR = 1.71, 0.24- 11.78 (95% CI)) and abortion (OR = 0.46, 0.07-2.95 (95% CI)) were not different between the two groups. No side effect of drug occurred in any group. Conclusion: A single dose of 20 mg nifedipine tablet administered thirty minutes before IVF had no effect on improving clinical pregnancy and live birth rate. Using higher doses, or different regimens in specific patients’ subgroups may have more effect on embryo transfer success.