Post Maturity


Literally, any pregnancy beyond the expected date of delivery is a postdated pregnancy. But medically, a pregnancy continuing beyond two weeks of the EDD (Expected Due Date) is called post maturity and about 10% of all pregnancies may go on to postmaturity.


Exact cause is not known, but contributory factors are

  • Heredity plays some role, as it often runs in the family and consecutive pregnancies in the same woman go on to post maturity.
  • High standard of living with sedentary habits often tends to prolong the pregnancy.
  • Certain congenital anomalies like anencephaly.
  • Elderly primigravidae or elderly multiparae are more likely to have prolonged pregnancy.
  • Previous history of a post-term pregnancy has a 50% chance of recurrence.


Diagnosis of the maturity of the fetus is much more important than that of postmaturity.
The following may be used by an obstetrician

  1. Menstrual History - If you are sure about your date with regular cycles prior to that, it is fairly reliable to calculate the period of gestation. But cases of mistaken dates or pregnancy occurring during lactation or soon after withdrawal of the 'pill', create confusion.
  2. The suspected clinical findings those are evident when an otherwise uncomplicated case overun the expected date by two weeks are
  • Weight loss: Regular periodic weight checking reveals stationary or even falling weight.
  • Girth of the abdomen: Normally, the girth of the abdomen at the level of the umbilicus increases steadily up to the completion of 38 weeks and then remains steady up to term. Thereafter, the girth gradually diminishes because of diminishing liquor.
  • History of false pain: Appearance of false pain followed by its subsidence with continuation of pregnancy is suggestive. The false pain is presumed to coincide with the expected date.
  • Obstetric palpation: Experience is needed to assess the maturity from casual palpation.


  • To confirm the fetal maturity
  • To detect evidences of placental insufficiency, if any


During Pregnancy
There is chance of fetal hypoxia, due to placental insufficiency

During Labor
There is increased incidence of intracranial damage and cord compression.
Following birth

  1. Meconium aspiration
  2. Hypoglycaemia


There is increased morbidity, incidental to hazards of induction and operative delivery. Postmaturity does not put the mother at risk.