Inducing Labor: When Mother Nature Needs Help Making You a Mother Sooner
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When should labor be induced?

Each decision to induce labor is based upon the balance between the risks if the baby stays inside the mother versus those if the baby is born, to both the mother and her child.  Induced labor is considered when the merits of delivering sooner outweigh the risks of delivering later.  There is only one indication for 'routinely' induced labor: in "postdates" pregnancies which have exceeded 42 well-documented, completed weeks.  This affects approximately one in 10 pregnancies and is defined as pregnancies which go more than 14 days past the assigned due date.   These pregnancies have been shown to have greatly increased risk of complications for the baby.  For example, studies of postdates pregnancies have found that the perinatal death rate doubles  after 42 weeks of pregnancy and triples after 43 weeks.  Even with the sophisticated monitoring techniques we have today, nearly 1 in 1000 babies will die unexpectedly before birth in pregnancies beyond 42 weeks.

In general, a fetus is better off growing inside the womb until "term", the point at which it is fully developed and ready for birth.  There are conditions, however, which affect the fetus which make earlier delivery--and treatment or continued growth outside the womb--preferable.  In addition to postdates pregnancy, these include macrosomia (when the fetus is excessively large); decreased amount or certain infections of the amniotic fluid; decreased fetal movement; intrauterine growth retardation (IUGR--when the fetus is not continuing to grow properly); maternal drug abuse or other toxicity; complications from blood factor incompatibility with mom; certain complications with multiple gestations; and intrauterine fetal death.

There are also conditions in which the mother's health is at risk if the pregnancy is further continued, and induction may be indicated.  These conditions may include uncontrolled maternal diabetes, pregnancy-induced hypertension, preeclampsia, eclampsia ("toxemia"), maternal heart disease, maternal renal failure, maternal stroke, certain unstable psychiatric conditions, certain infections, certain liver or autoimmune diseases, or cancer.  While these conditions may also sometimes require planned or immediate cesarean sections, induced labor is often a preferred first step.  Other conditions in which induction of labor are increasingly common include premature rupture of membranes (PROM--when the mom's water breaks before she goes into labor) and cases where labor has begun and then stopped or in which it is progressing too slowly. 

Some physicians believe that well-timed inductions can actually prevent the need for cesarean sections in some women, particularly those with large babies, babies in the breech position, or multiple gestations (twins, triplets, etc.).  These decisions must be made on an individual patient basis, however.