Pathogenesis (development of disease)
Usually, the condition is an acquired rectus diastasis.
Pregnant women physiologically have rectus diastasis at the time of delivery. The gap between the straight abdominal muscles expands to make room for the growing baby, causing the right and left straight abdominal muscles to deviate to the side. This often occurs in the last trimester (third trimester) of pregnancy. The pregnancy hormones, especially relaxin, help loosen joints and ligaments in the third trimester (last trimester of pregnancy).
Typically, this gap recedes on its own within the first 6 months postpartum (after birth).
Etiology (causes)
Biographic causes
- Weakness of connective tissue → abdominal wall weakness.
Behavioral cause
- Physical activity
- Heavy lifting and carrying during pregnancy
- Extreme abdominal exercises during pregnancy
- Intensive strength training
- Overweight (BMI ≥ 25; obesity).
Other causes
- Pregnancy, in particular:
- Multiple pregnancy
- Polyhydramnios – larger than average amount of amniotic fluid with an amniotic fluid index (AFI) greater than 20 cm or with a large amniotic fluid depot greater than 8 cm (greater than two liters at term)
- Repeated pregnancies