Sexual Intercourse on Spontaneous Onset of Labor

The study involved pregnant women who were randomly assigned to 2 groups. The protocol involved engaging in sexual intercourse and nipple stimulation 3 times per day for two consecutive weeks with the consecutive days of sexual intercourse and days of nipple stimulation being different. Patients documented their coital activities as well as the frequency of orgasms in their daily journal. There were no prohibitions regarding or promotions of sexual activities for the control group. The main outcome was the onset of labor, which was defined as the presence of effective uterine contraction with changes of the cervix (Bishop score \> 5) without using the induction treatments during protocol time or until 41 weeks of pregnancy.