Abstract
INTRODUCTION: 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. METHODS: 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. RESULTS: 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). CONCLUSION: 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.