A postmature birth occurs when a human pregnancy lasts longer than three weeks past the expected delivery date. In such a birth the placenta can begin to fail, causing declining delivery of oxygen and nutrients to the fetus. This can result in the death of the fetus if delivery is not induced. Postmature newborns are typically thin and underweight, with slender limbs, dry wrinkled skin and longer hair and nails. The first few days after delivery are the most critical. Infants that live beyond that period have a high survival rate.
- Clifford SH. Postmaturity with placental dysfunction. Clinical syndromes and pathologic findings. J Pediatr 1954;44:1-13