Introduction and hypothesis: Multiparity, age and high body mass index (BMI) are the most widely investigated factors associated with urinary incontinence (UI) during pregnancy. We hypothesized that multiparity, age 35 years or older and high BMI (prepregnancy and during pregnancy) are risk factors for the occurrence of UI in pregnant women.
Methods: Searches were done on MEDLINE/PubMed (1966-2017), LILACS/BIREME (1982-2017), CINAHL/Ebsco (1981-2017) and Scopus/Elsevier (1950-2017). The following criteria were used for study eligibility: (1) population: low-risk pregnant women in any trimester and without age restriction; (2) exposure factors: multiparity (≥ 2 deliveries), age 35 years or older and high BMI (overweight and obesity); (3) outcome: UI during pregnancy; (4) study design: cohort, case-control or cross-sectional studies that used multivariate logistic analysis. Two independent reviewers performed the entire systematic review process. Data extraction of each article was done and, when possible, included in a meta-analysis. Risk of study bias was assessed by NOS and quality of evidence by GRADE. A significance level of p ≤ 0.05 was adopted. The PROSPERO registration number was CRD42014013193.
Results: Of 1176 articles identified through searches, 13 were included after screening and application of eligibility criteria. Very low quality of evidence shows that multiparity (OR = 2.09; 95% CI: 1.07 to 4.08), age 35 years or older (OR = 1.53; 95% CI: 1.45 to 1.62) and overweight and obesity during pregnancy (OR = 1.53; 95% CI: 1.28 to 1.83) are risk factors for UI in pregnancy.
Conclusions: The exposure factors investigated are risk factors for UI in pregnancy based on a very low quality of evidence.
Keywords: Pregnant women; Risk factors; Urinary incontinence.