Inducing Labor: When Mother Nature Needs Help Making You a Mother Sooner
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When should induction not be done?

ACOG generally does not recommend inducing labor before 39 weeks gestation, especially when maternal and fetal health are stable.  As with all decisions regarding a pregnancy, the decision to induce is made between the physician and the parents, and the risk benefit ratio to the mother and child are the most important factors in that decision.  In general, inductions for parental or physician convenience generally are not indicated and not appropriate. . . as tempting as they may be.  Nonetheless, as the rate of induced labor has increased, the percentage of babies born on weekends has decreased; Tuesday is now the most common day of the week for US births.  There is also a rush to induce babies in the end of December as folks scramble to make IRS deduction deadlines, pursue holiday plans, and hope for New Years babies.

There are also contraindications to inducing labor; these are reasons it absolutely should not be performed.  These include any condition which contraindicates a vaginal delivery such as placenta previa (when the placenta is coming before the baby); certain abnormal positions of the baby (e.g. "transverse lie" when the baby is lying sideways inside the womb); prolapsed umbilical cord (when the cord is coming through before the baby); history of prior cesarean section with and up and down incision; active genital herpes; and of course, patient refusal.

There are several techniques used--alone, or in combination--to induce labor.  Sometimes, physicians simply recommend intercourse to accelerate this process!  This is not just an old wives' tale:  sperm and penetration both act upon the cervix independently to stimulate dilation and uterine contractions.  Nipple stimulation also independently stimulates uterine contractions by causing a release of the body's own oxytocin, the hormone responsible for breast milk "let-down" as well.  Conversely, physicians advise against both of these activities in women who have had or are at risk for premature labor. 

The most commonly used method to induce labor is called "stripping (or stretching) the membranes", although many research studies challenge its effectiveness.  This is done during an internal exam, either in the doctor's office or in the exam room in a woman whose cervix has already begun to thin and dilate significantly.  This is generally done when a woman has passed her due date just to speed things up a little.  One of the risks of this procedure, however, is rupturing the placental membranes ("breaking the water bag") prematurely; another is that the cord might prolapse, or sneak ahead of the baby's head causing decreased blood supply to the baby and fetal distress (abnormal fetal heartbeat patterns).  In some cases, however, when the cervix is well dilated and the membranes are easily accessible but active labor has not yet begun, a physician may choose to rupture the membranes ("amniotomy") as a way of beginning active labor, thus committing to delivery within 24 hours.

The other methods of labor induction don't require cervical dilation, but do work better when the cervix is "ripe", or ready for labor.  This means it is soft and starting to thin.  Drugs such as cervical prostaglandin inserts or gels or misoprostol are often administered to help the cervix ripen and to start early contractions (NB:  misoprostol is not FDA approved for this purpose, however). Inducing labor before the cervix is ready raises the risk of "failed induction" leading to an increased use of forceps, vacuum extraction or cesarean section and the complications related to those additional procedures.

Stripping the membranes or otherwise preparing the cervix can often stimulate uterine contractions; in many cases, however, women are given intravenous drugs such as oxytocin or Pitocin  (nicknamed "Pit") to start or accelerate uterine contractions.  Women being induced with Pitocin require continuous electronic fetal monitoring as well as close observation.  The dose is usually gradually increased, and many women complain that Pitocin-induced labor is significantly more intense and painful.  In addition, continuous fetal monitoring may be uncomfortable for the mother, and limits her to bedrest.

Many nurse-midwives use herbal preparations to promote cervical ripening and stimulate labor. However, little scientific research supports the use and safety of these substances. Several of the commonly used agents appear to be safe at low dosages although safety and efficacy have not been proven.