A 29-year-old G2P1 with one prior uncomplicated lower segment cesarean section requests elective repeat cesarean delivery. Her obstetrician plans the surgery. The main reason elective repeat cesarean is scheduled at 39 completed weeks rather than earlier is:

• A Uterine rupture risk rises steeply if labour starts before 39 weeks
• B Wound infection rates fall sharply between 38 and 39 weeks
• C Neonatal respiratory morbidity is significantly higher at 37 to 38 weeks compared with 39 weeks ✓
• D Fetal lung maturity testing is unreliable before 39 weeks

Explanation

Elective cesarean before 39 weeks carries a higher rate of neonatal respiratory morbidity, mainly transient tachypnoea of the newborn and respiratory distress syndrome, because surfactant maturation is incomplete and labour-related catecholamine clearance of lung fluid is bypassed. Waiting until 39 weeks substantially reduces NICU admission. Uterine rupture risk relates to labour onset rather than gestational age itself, and amniocentesis for lung maturity was historically used precisely because dates were uncertain.

Reference: Williams Obstetrics, 26th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.