OBJECTIVE We investigated the effect of repeat cesarean sections (CSs) and intra-abdominal adhesions on neonatal and maternal morbidity. METHODS We analyzed intra-abdominal adhesions of 672 patients. RESULTS Among the patients, 173, 206, 151, and 142 underwent CS for the first, second, third, and fourth time or more, respectively. There were adhesions in 393 (58.5 %) patients. Among first CSs, there were no adhesions, the rate of maternal morbidity [Morales et al. (Am J Obstet Gynecol 196(5):461, 2007)] was 26 %, and the rate of neonatal morbidity (NM) was 35 %. Among women who have history of two CSs, the adhesion rate was 66.3 %, the adhesion score was 2.05, MM was 14 %, and NM was 21 %. Among third CSs, these values were 82.1, 2.82, 23, and 14 %, respectively. Among women who have history of four or more CSs, these values were 92.2, 4.72, 31.7, and 18 %, respectively. Adhesion sites and dense fibrous adhesions increased parallel to the number of subsequent CSs. Increased adhesion score was associated with 1.175-fold higher odds of NM and 1.29-fold higher odds of MM. The rate of NM was eightfold higher in emergency-delivered newborns (emergency: 39.4, 40 %; elective: 4.9 %). MM was 20 and 26 % for elective and emergency CSs, respectively. CONCLUSIONS Emergency operations and adhesions increased complications.