The ultrasound diagnostic criteria for diastasis recti and its correlation with pelvic floor dysfunction in early postpartum women

Background: There has been a long-standing controversy about diastasis recti diagnostic criteria and its relation to pelvic floor dysfunction (PFD). This study aimed to establish ultrasound diagnostic criteria for diastasis recti and investigate the correlation between it and PFD in early postpartum females.

Methods: The inter-rectus distance (IRD) was measured at 3 locations in 116 healthy nulliparous females and 108 postpartum females. At the same time, they remained relaxed and then maintained a head-lift posture. The measurement for the 90th percentile was used to define the normal IRD in the nulliparous group. Afterward, the 108 postpartum females underwent an ultrasonographic examination of pelvic floor function. The correlations of these values with the IRD were then examined.

Results: We established the following ultrasonographic diagnostic criteria for diastasis recti: an IRD of >2 mm at 3 cm below the umbilicus, >20 mm at the umbilicus, and >14 mm at 3 cm above the umbilicus. The IRD was positively correlated with body mass index (BMI) in the nulliparous group (r=0.286, P<0.01) and with age in the postpartum group (r=0.230, P<0.05). The IRD was not relative to either the PFD ultrasound results or the clinical symptoms.

Conclusions: We established a set of ultrasonographic diagnostic criteria for diastasis recti at 3 locations along the umbilicus. There is no clear correlation between diastasis recti and PFD in early postpartum females.