Post term labour is seen in:

Causes of Post-term pregnancy: Wrong dates: due to inaccurate LMP (most common). Biologic variability (Hereditary) may be seen in the family. Maternal factors: Primipara/elderly multipara/H/o previous prolonged pregnancy, sedentary habit. Fetal factors: Congenital anomalies: Anencephaly – (Abnormal fetal HPA axis), adrenal hypoplasia (Diminished fetal cortisol response). Placental factors: Sulphatase deficiency (Low oestrogen).