Background/aim Diastasis recti abdominis (DRA) is defined as a separation of the 2 muscle bellies of rectus abdominis. To date there is scant knowledge on prevalence, risk factors, and consequences of the condition. The present study aimed to investigate the prevalence of DRA during pregnancy and post partum, presence of possible risk factors, and the occurrence of lumbopelvic pain among women with and without DRA.

Methods This prospective cohort study followed 300 first-time pregnant women from pregnancy till 12 months post partum. Data were collected by electronic questionnaire and clinical examinations. DRA was defined as a palpated separation of ≥2 fingerbreadths either 4.5 cm above, at or 4.5 cm below the umbilicus. Women with and without DRA were compared with independent samples Student's t-test and χ²/Fisher exact test, and OR with significance level >0.05.

Results Prevalence of DRA was 33.1%, 60.0%, 45.4%, and 32.6% at gestation week 21, 6 weeks, 6 months and 12 months post partum, respectively. No difference in risk factors was found when comparing women with and without DRA. OR showed a greater likelihood for DRA among women reporting heavy lifting ≥20 times weekly (OR 2.18 95% CI 1.05 to 4.52). There was no difference in reported lumbopelvic pain (p=0.10) in women with and without DRA.

Conclusions Prevalence of mild DRA was high both during pregnancy and after childbirth. Women with and without DRA reported the same amount of lumbopelvic pain 12 months post partum.