Recurrent anterior cutaneous nerve entrapment syndrome (ACNES) in three consecutive pregnancies

Abstract

A 31-year-old G2P1001 woman at a 30-week gestation presented with a recurrence of pinpoint right upper abdominal wall pain. She had been diagnosed with an anterior cutaneous nerve entrapment syndrome (ACNES) during her first pregnancy at a similar gestational age, a well-described but frequently under-recognised entity. The pain during that pregnancy resolved immediately and completely following normal spontaneous vaginal delivery, however,the pain was worse with this presenting pregnancy. She underwent an ultrasound-guided rectus sheath nerve block at 30 weeks with complete and immediate relief for the remainder of the pregnancy. During a third pregnancy, she suffered another recurrence; however, it was less severe than in the prior pregnancies and was managed conservatively. It again resolved completely and immediately with normal spontaneous vaginal delivery. The pattern of ACNES recurrence during the same gestational age in all three pregnancies with total relief following deliveries demonstrates a clear primary mechanical aetiology.