Decidualised Caesarean Scar Endometriosis in a Gravid Woman: A Case Report

Endometriosis is a pathological condition characterised by the presence of extrauterine endometrial tissue that responds to hormonal variations. Globally, endometriosis affects approximately 89 million females, accounting for a 5-10% prevalence of the disease. Cutaneous endometriosis over abdominal surgical sites accounts for less than 1% of all cases, of which 0.03-0.45% occur following a lower segment caesarean section. Only a few cases of hormonal decidualisation of scar endometriosis during pregnancy have been reported. A 27-year-old G2P1L1 pregnant woman presented with pain and tenderness over a previous Lower Segment Caesarean Section (LSCS) scar, occurring intermittently over three years. Clinicoradiological evaluation suggested scar endometriosis, which was subsequently confirmed histopathologically as decidualised scar endometriosis. The most widely accepted theory is that direct inoculation of endometrial tissue during surgical procedures is the major predisposing factor for scar endometriosis, particularly in cases involving hysterectomy at a young age or procedures performed for abortion. Scar endometriosis is an infrequent yet challenging condition following obstetric and gynaecological surgeries, including caesarean section. Therefore, this condition must be considered as a differential diagnosis in patients presenting with pain or a mass over a previous LSCS scar.