Effect of Intercourse on Less Need to Induction at Term

Document Type : Original Article


1 Associate Professor of Obstetrics and Gynecology, Women's Health Research Centre, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Resident of Obstetrics and Gynecology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

3 Specialist in Social Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.

4 Medical Student, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.


Introduction: Delivery is the final and the most important part of pregnancy, and ripening of cervix is one of the main aspects of labor progress. Coitus in late pregnancy may stimulate cervical ripening and secrete prostaglandin which may lead to uterine contractility and labor onset. The aim of this study was to evaluate the relationship between sexual intercourse and onset of labor and prevention of post term pregnancy.
Methods: This prospective study was held on 212 pregnant women over 39 weeks of low-risk referred to gynecology clinics at Ghaem and Omolbanin hospitals. Samples were selected by non-probable method based on objectives. Eligible individuals were chosen and categorized into two groups of control (102 persons) and case (110 persons). The Control group had no sexual intercourse until delivery. In case group first vaginal examination and Bishop Score determination and non-stress were done then they had sexual intercourse from the week 39 once or twice a week. Collected data were analyzed by the statistical SPSS software version 16, t-test, chi-square and Mann-Whitney tests. P value less than 0.05 was considered statistically significant.
Results: The mean gestational age in two group had not significant different (p=0.3), need to stimulated delivery (p<0.0001), and rate of cesarean section (p<0.034) were significantly lower while the Bishop scores was higher in the case group (p<0.002). There was no difference in post term pregnancy (p<0.88) and complication of delivery (p<0.68) between two groups.
Conclusion: Sexual intercourse at term may be associated with an earlier spontaneous onset of labor and less need to induction of labor and low cesarean section.


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