Beneficial effect of l-arginine in women using assisted reproductive technologies: a small-scale randomized controlled trial.

This small-scale randomized controlled study aimed to examine the effect of l-arginine supplementation on the human chorionic gonadotropin (hCG)-positive rate and clinical pregnancy rate (CPR) in women undergoing assisted reproductive technology (ART) treatment for 3 months. From November 2017 to March 2018, 120 patients aged less than 40 years and planning for egg retrieval for embryo transfer were enrolled. The patients were divided into the AS2000 group (n = 36; l-arginine, 2 g; folate, 400 μg; and vitamin E, 10 mg), AS1000 group (n = 37; l-arginine, 1 g; and folate, 200 μg), and control group (n = 36). The main outcome was the hCG-positive rate or CPR in 3 months. The cumulative hCG-positive rates during the administration period were 44.2%, 54.2%, and 52.1%, and the CPRs were 39.5%, 41.7%, and 47.9% in the control, AS1000, and AS2000 groups, respectively. Odds ratios of the hCG-positive rate and CPR in the global l-arginine group (AS1000 and AS2000) versus those in the control group were 1.33 (95% confidence interval [CI], 0.62-2.90) and 1.11 (95% CI, 0.51-2.46), respectively. In the subgroup of women receiving ART because of male infertility, the hCG-positive rate and CPR were significantly increased in the l-arginine groups compared to those in the control group (13.42 [95% CI, 1.42-366.9] and 13.62 (95% CI, 1.42-367.6), respectively). Thus, arginine supplementation may be an option for women who desire pregnancy, especially those undergoing an ART program because of male infertility.