Postterm Pregnancy is Not an Indication for Cesarean Section
Postterm pregnancy alone is not an indication for cesarean section (CS). The mode of delivery should be determined based on obstetric indications rather than gestational age alone 1.
Definition and Management of Postterm Pregnancy
- Postterm pregnancy is defined as a pregnancy that has reached 42 weeks' gestation (294 days), while late-term pregnancy includes 41 weeks' and 0 days' to 41 weeks' and 6 days' gestation 1, 2.
- Accurate first-trimester dating is essential for determining or verifying gestational age to properly identify postterm pregnancies 1.
- The risks of fetal mortality, stillbirth, and neonatal intensive care unit admission increase exponentially starting at 42 weeks' gestation 1, 3.
Evidence-Based Management Approach
Induction vs. Cesarean Section
- Induction of labor before 42 weeks of gestation decreases the risk of stillbirth, perinatal mortality, and cesarean delivery compared with expectant management 1.
- Induction of labor at 41 weeks' gestation reduces perinatal mortality and stillbirth compared with expectant management or induction starting at 42 weeks' gestation 1, 3.
- The American College of Obstetricians and Gynecologists recommends:
Vaginal Delivery Preference
- Vaginal delivery is preferred where possible, even in high-risk cases, with cesarean section reserved for obstetric indications 4.
- There is no absolute obstetric contraindication for vaginal delivery based solely on gestational age 2, 3.
Special Considerations
Maternal Conditions
- In women with certain cardiac conditions, individualized delivery plans should be made with support from a multidisciplinary team, but gestational age alone does not dictate cesarean section 4.
- For women with vascular liver disease, delivery should be performed for obstetric indications, not based on gestational age alone 4.
Fetal Assessment
- Antepartum monitoring should be implemented for pregnancies at or beyond 41 weeks' gestation 1.
- If induction is chosen, procedures for cervical ripening should be used, especially in nulliparous women 2.
Potential Complications of Cesarean Section
- Cesarean section carries risks including:
- Chronic wound pain (15.4% at 3-6 months postpartum) 4.
- Increased risk of placenta previa and accreta in subsequent pregnancies 4.
- Uterine rupture in subsequent pregnancies (22 per 10,000 births in women with previous CS) 4.
- Venous thromboembolism (2.6 per 1000 CS births) 4.
- Secondary infertility (reported in up to 43% of women) 4.
Common Pitfalls to Avoid
- Performing cesarean section based solely on gestational age without obstetric indications increases maternal morbidity without clear benefit 3.
- Failing to distinguish between true postterm pregnancy (≥42 weeks) and late-term pregnancy (41+0 to 41+6 weeks) when making management decisions 1.
- Not considering induction of labor as a safer alternative to expectant management for pregnancies beyond 41 weeks 1, 3.
In conclusion, while postterm pregnancy requires careful monitoring and often induction of labor, it does not by itself constitute an indication for cesarean section. The decision for cesarean delivery should be based on standard obstetric indications rather than gestational age alone.