Delayed residual intra-abdominal abscess with threatened preterm labor after laparoscopic appendectomy in the second trimester.

Acute appendicitis is the most common non-obstetric surgical emergency in pregnancy. We report a 30-year-old primigravida at 25 weeks' gestation who underwent laparoscopic appendectomy for appendicitis with localized peritonitis. Thirteen days later, she represented with worsening lower abdominal pain, vomiting, leukocytosis, vaginal bleeding, and uterine contractions. Ultrasound showed a right lower abdominal collection and a viable 27-week fetus. Magnetic resonance imaging demonstrated a peri-cecal abscess adherent to the uterus with associated intraperitoneal fluid suspicious for purulent peritonitis. After obstetric management and tocolysis, emergency surgery confirmed diffuse purulent peritonitis and a residual abscess adjacent to the prior appendectomy site. Drainage, lavage, and drain placement achieved maternal stabilization. No recurrent postoperative complication occurred, and the pregnancy progressed uneventfully to 39 weeks. Cesarean delivery resulted in a healthy 3200 g neonate with normal Apgar scores. This case highlights vigilance for delayed postoperative infection in pregnancy and timely imaging escalation with definitive source control.