Prevalence of Symptomatic Established Rectus Diastasis of Parity in Primiparous Women: A Prospective Cohort Study From Early Pregnancy to 1-Year Postpartum.

Abstract

Rectus diastasis of parity is the separation of the abdominal muscles that can occur after childbearing. We hypothesized that a subpopulation of women with rectus diastasis also present with back pain and/or urinary incontinence, a condition referred to as symptomatic established rectus diastasis, and this results in impaired health-related quality of life. This study identified the prevalence of symptomatic established rectus diastasis in primiparous women and measured their health-related quality of life. Gravid nulliparous women over 18 years old were consecutively recruited from December 2021 to August 2022 and followed prospectively. Inter-rectus distances were measured with ultrasound in early pregnancy, and 6-week, 6-month, and 12-month postpartum. Patient reported outcome measures included the Oswestry Disability Index (ODI) for back pain, International Consultation on Incontinence Questionnaires Urinary Incontinence Short Form (ICIQ-UI SF) for urinary incontinence, and the 36-item short form (SF-36) for health-related quality of life. Two-hundred and thirteen women were recruited, of which 192 underwent ultrasound measurement in early pregnancy, 130 at 6-week postpartum, 120 at 6-month, and 109 at 12-month. There was a significant increase in mean inter-rectus distance over the study period (p < 0.001). The proportion of women with rectus diastasis at 12-month postpartum (> 30 mm) was 30.3% and compared to those without they had worse back pain (p = 0.014) but no difference in urinary incontinence (p > 0.05). Women with symptomatic established rectus diastasis at 12-month postpartum (rectus diastasis and back pain (ODI > 0)), made up 25% of the cohort and had significantly worse health-related quality of life than those without (p < 0.05). Predictive factors for symptomatic established rectus diastasis included increased total fetal birthweight (OR 3), lower maternal BMI (OR 1.2), and gestational diabetes (OR 6.7). This study of gravid nulliparous women from early pregnancy until 12-month postpartum identified rectus diastasis in 30.3% and symptomatic established rectus diastasis in 25%. Women with symptomatic established rectus diastasis had significantly worse health-related quality of life.