ABSTRACT
The prevalence of prolonged pregnancy varies depending on population characteristics and local management practices. The proportion of women with pregnancy complications and the frequency of spontaneous preterm labour also influence the rate of prolonged pregnancy. Local management practices such as scheduled induction of labour, differences in the use of early ultrasound for pregnancy dating, and elective caesarean section rates will affect the overall prevalence of prolonged pregnancy. Incidence of prolonged pregnancy occurs in 5–10 percent of all pregnancies. The most common cause of prolonged pregnancies is inaccurate dating. Fetal adrenal insufficiency and fetal adrenal hypoplasia are associated with prolonged pregnancies. Male fetuses, hormonal factors, genetic predisposition and obesity are all associated with increasing the risk for a prolonged pregnancy. Prolonged pregnancy is associated with post-maturity syndrome. Accurate pregnancy dating is crucial in the diagnosis and management of prolonged pregnancy. Membrane sweeping is the only evidence-based intervention known to reduced prolonged pregnancy.
