Relationship between transversus abdominis muscle thickness and urinary incontinence in females at 2 months postpartum

[Purpose] Urinary incontinence is a frequent postpartum complication. Thus, this study aimed to examine the associations of transversus abdominis muscle thicknesses at rest and during an abdominal drawing-in maneuver with urinary incontinence in females at 2 months postpartum. [Participants and Methods] The participants included 18 females at 2 months postpartum with or without urinary incontinence, and 10 nulliparous females as controls. Transversus abdominis thickness was measured at rest and during the abdominal drawing-in maneuver using diagnostic ultrasonography. The Japanese version of the International Consultation on Incontinence Questionnaire-Short Form was used to evaluate urinary incontinence. [Results] Females at 2 months postpartum were divided into groups with and without urinary incontinence according to questionnaire scores. The muscle thickness during the abdominal drawing-in maneuver contraction was significantly lower in those with urinary incontinence than in those without urinary incontinence and controls. [Conclusion] The results showed significantly reduced transversus abdominis thickness during contraction, which suggested reduced transversus abdominis strength in females with postpartum urinary incontinence. Thus, promoting synergistic contraction of the inner unit, including the transversus abdominis, in exercise therapy may be more effective for postpartum urinary incontinence.