[Impact of twin gestation on the risk of postpartum stress incontinence]

To study twin pregnancy and delivery as a risk factor for developing postpartum stress urinary incontinence (SUI).

Retrospective single centre study comparing 117 patients who have delivered twins to 117 patients who have given birth to singletons, between January 2003 and December 2005 in a tertiary maternal-foetal medicine unit. The risk factors associated with the onset of postpartum SUI, its severity, and its impact on the quality of life were studied.

Sixty patients in the twin pregnancy group and 59 in the singleton pregnancy group have answered an auto-questionnaire and were included in the study. The medium-term follow-up of the patient was 20.2 months+/-10.1. The prevalence of SUI in the total population was 30%. The rate was significantly higher in the "twin" group (40%) than in the "singleton" group (20%) (p=0.03). Twin gestation was significantly associated with postpartum SUI for more than 20 months after delivery (OR=2.6 [1.1-5.9]). The univariate analysis found six other risk factors: prenatal urinary incontinence (OR=4.2 [1.7-10.4]), BMI greater than 30 (OR=6.3 [1.2-34.1]), labour duration greater than 8h (OR=4.8 [1.6-14.5]), fundal uterine pressure (OR=4.5 [1.1-18.3]), total intrauterine foetal weight (p=0.003), and immediate postpartum urinary incontinence (OR=12.9 [5-33.5]).

The vaginal delivery of two successive foetuses does not seem more purveyor of SUI than caesarean. In twin pregnancies, the high rate of postpartum SUI appears to be related to total intrauterine weight.