Comparing the Effect of Nigella sativa oil Soft Gel and Placebo on Oligomenorrhea, Amenorrhea and Laboratory Characteristics in Patients with Polycystic Ovarian Syndrome, a Randomized Clinical Trial

Background and objectives: Oligo-amenorrhea is one of the most common symptoms in poly cystic ovarian syndrome (PCOS) patients and Nigella sativa is a medicinal plant used in Iranian traditional medicine for the treatment of oligo-amenorrhea. The aim of this study was to evaluate the effect of N. sativa oil on oligo-amenorrhea in patients with PCOS. Methods: This study was a double-blinded placebo-controlled clinical trial conducted on 84 PCOS patients with oligo-amenorrhea. Patients were randomly assigned to intervention and placebo group. They used two soft gel capsules of N. sativa oil (500 mg, each capsule) or placebo at night for sixteen weeks. Four indices were used to assess menstruation; the interval between menstruations, duration of menstruation, the occurrence of menstruation and the severity of bleeding. The two groups were compared using analysis of covariance. Result: Fifty five patients completed the study (32 patients in N. sativa group and 23 patients in placebo group). The menstrual interval after the study in the intervention group (45 days, 95% CI) was significantly lower than the control group (86 days). The frequency of menstrual cycle in the intervention group (0.79) was significantly higher than the placebo group (0.48). No serious complication was reported in this clinical trial. Conclusion: findings suggest that N. sativa is an alternative treatment and could be useful for menstrual irregularities in women with PCOS. Further studies are recommended to find the exact mechanisms of N. sativa and its different derivatives.