The laxity of the symphysis pubis ligament occurs in early pregnancy and worsens as the weeks of pregnancy increase, even causing separation of the pubic bone, which can be asymptomatic in mild cases or painful at the pubic bone in severe cases.
The separation of the symphysis pubis may also be caused or aggravated during labour if there is an emergency birth, difficult labour, cephalopelvic disproportion, multiple births, forceps delivery, etc., causing pain. The widening of the symphysis pubis gap is visible on imaging, but the degree of pain does not show a positive correlation with the widening of the gap.