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Labor and Timing Problems

By Julie S. Moldenhauer, MD

  • Labor may start too early (before the 37th week of pregnancy) or may start late (after the 42nd week of pregnancy).

  • As a result, the health or life of the fetus may be endangered.

  • Labor may start too early or late when the woman or fetus has a medical problem or the fetus is in an abnormal position.

  • An ultrasound examination can help determine the length of a pregnancy.

No more than 10% of women deliver on their specified due date (usually estimated to be about 40 weeks of pregnancy). About 50% of women deliver within 1 week (before or after), and almost 90% deliver within 2 weeks of the due date.

Did You Know...

  • Only about 10% of women deliver their baby on their due date.

Determining the length of pregnancy can be difficult because the precise date of conception often cannot be determined. Early in pregnancy, an ultrasound examination, which is safe and painless, can help determine the length of pregnancy. In mid to late pregnancy, ultrasound examinations are less reliable in determining the length of pregnancy.

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