Coitus and orgasm at term: effect on spontaneous labour and pregnancy outcome

Tan PC, Yow CM, Omar SZ 
Correspondence: Prof Peng Chiong Tan, pctan@um.edu.my

ABSTRACT
Introduction Coitus and orgasm in late pregnancy are believed to facilitate the onset of labour. We aim to evaluate the relationship at term of reported coitus and orgasm with spontaneous labour. 
Methods Women at term scheduled for non-urgent labour induction were asked to keep a coitus and orgasm diary. These women were recruited for a randomised trial on the effect of coitus to promote spontaneous labour. For this analysis, the women were categorised into coitally-active and abstinent groups according to their coital diary. Spontaneous labour prior to the date of scheduled labour induction was the primary outcome. Labour, delivery and neonatal outcome were also evaluated. Multivariable logistic regression analysis was used to control for significant variables.
Results On univariate analysis, the inverse association of coitus with spontaneous labour was borderline (odds ratio [OR] 0.6; 95 percent confidence interval [CI] 0.3–1.0; p-value is 0.052). Orgasm was not associated with spontaneous labour (p-value is 0.33). After adjustment, coitus (adjusted OR 0.4; 95 percent CI 0.2–0.8; p-value is 0.009) displayed a significant inverse association with spontaneous labour. Coitus and orgasm were not associated with any other adverse pregnancy outcome.
Conclusion Women who reported coitus were less likely to go into spontaneous labour prior to their scheduled labour induction. Reported coitus and orgasm were not associated with adverse pregnancy outcome.