Effect of parity on sexual function: an identical twin study.

OBJECTIVE

To assess the impact of childbirth on female sexual function by using an identical twin study design.

METHODS

A survey including the Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12) was administered to 542 twin sisters, and PISQ-12 scores of 29 twin pairs discordant for parity were compared. Multiple linear regression models were used to evaluate impact on total PISQ-12 scores in 276 identical, sexually active twins. Three models were used 1) to evaluate the effect of parity and general risk factors, 2) to examine the impact of birth mode, and 3) to examine the role of episiotomy and operative delivery.

RESULTS

Mean PISQ-12 scores were significantly higher for discordant nulliparous twins than for parous twins (102.5 versus 93.5, P < .001). The mean (standard deviation) PISQ-12 score was 99.3 (11.7). Age of 50 years or older (difference in mean scores -5.4, P = .019), stress urinary incontinence (-3.3, P = .02), urge urinary incontinence (-5.9, P < .001), parity (-6.5, P < .001), and fecal incontinence (-5.7, P = .048) were associated with decreased mean PISQ scores in the univariable analysis. Parity (-4.9, P < .001) and urge urinary incontinence (-4.3, P = .009) were the only factors remaining independently predictive of diminished sexual function in the multivariable analysis. Mode of delivery did not significantly affect mean PISQ scores (P = .763). Among women who had vaginal deliveries only, neither episiotomy nor operative delivery was associated with change in PISQ scores (P = .553).

CONCLUSION

Nulliparous women reported superior sexual satisfaction scores compared with parous women, regardless of age and mode of delivery. Childbirth appears to have a lasting impact on sexual function, due to psychological more than physical factors, well beyond the postpartum period.

LEVEL OF EVIDENCE

II-2.