Scar endometriosis after a caesarean section: a perhaps underestimated complication

The exact incidence of scar endometriosis is unknown. The aim of this study is to determine the incidence of endometriosis in the abdominal wall following a caesarean section. Women who underwent surgery for scar endometriosis after a caesarean section and the total number of women with caesarean sections in The Haga Teaching Hospital, a gynaecologic centre in The Netherlands, were identified by the national obstetric registration and pathology archive in the period January 1995 to December 2008. Clinical data were collected from the existing hospital records. Twenty-nine women were diagnosed with scar endometriosis after a caesarean section, and 3,047 women underwent one or more caesarean sections, resulting in an incidence of scar endometriosis of 0.95 %. None of the women had a history of endometriosis. Symptoms were pain (94.0 %), cyclic with menstruation (50.0 %) and swelling of the scar (89.0 %). Mean time between caesarean delivery and symptoms was 4.1 years. No recurrence occurred. This study reveals a higher incidence of endometriosis in the scar of a caesarean section than described in current literature. To improve the detection rate, more attention to medical history and physical examination is mandatory. A higher incidence warrants research into the pathophysiology and prevention of endometriosis in the scar of a caesarean section.