Postterm and postmature infants

[Greta]

A postterm infant is an infant born after 42 weeks gestation. A postmature infant is a postterm infant with manifestations of dysmaturity.
The cause of postmaturity is generally unknown, but previous postterm delivery increases the risk 2- to 3-fold. Postmaturity may be caused by abnormalities that affect the fetal pituitary-adrenal axis (eg, anencephaly, adrenal gland hypoplasia, congenital adrenal hyperplasia) and by x-linked ichthyosis associated with placental sulfatase deficiency.