Will You Induce My Labor?

Inducing Labor and Extraordinary Circumstances

Ensure your obstetrical care provider will not unnecessarily induce labor just because the the baby is suspected to be "big" on ultrasound measurements.  There are specific ACOG guidelines for when it is advisable to induce for a large estimated fetal weight.  Unless there are other contributing factors to indicate an induction is necessary, with proper positioning, many women can birth babies in the 9-11lb range vaginally without issue.


Will you induce my labor prior to 42 weeks if the estimated fetal weight is "large"?


If the baby is suspected to be “big” using ultrasound assessments in the 3rd trimester, and if your care provider is pressuring you to be induced because the baby is “big,” please be aware that the Practice Standards set forth by ACOG states that if the baby has an estimated fetal weight of less than 5000 grams (11.02 lb.) and the mother is not diabetic, or if the baby has an estimated fetal weight of less that 4500 grams (9.92 lb.) and the mother has diabetes, induction only for “macrosomia” (big baby) is NOT indicated, unless there are other factors that enter into the decision making, such as previous birth history, a previous shoulder dystocia, constitutional stature, etc.  Many women can birth babies in the 9-11 lb. range vaginally with no problems if their babies are assisted into the correct fetal position during the birth.  Also, be aware that the estimated fetal weight generated by ultrasound in the third trimester is extremely inaccurate, generating a weight plus or minus a pound and a half on either side. Often women are subjected to the medical risks of induction for an estimated fetal weight of an “expected” 9 lb. baby, and the baby ends up being 7 lb. 8 oz. You should discuss all risks and benefits of expectant management versus medical induction with your care provider.

Sources:

  • Bergmann RL, Richter R, Bergmann KE, Plagemann A, Brauer M, Dudenhausen JW Secular trends in neonatal macrosomia in Berlin: influences of potential determinants Paediatr Perinat Epidemiol 2003 17 244–9 doi:10.1046/j.1365-3016.2003.00496.x.,
  • Bonellie SR, Raab GM Why are babies getting heavier? Comparison of Scottish births from 1980 to 1992 BMJ 1997 315 1205.
  • Kramer MS, Morin I, Yang H, Platt RW, Usher R, McNamara H et al Why are babies getting bigger? Temporal trends in fetal growth and its determinants J Pediatr 2002 141 538–42 doi:10.1067/mpd.2002.128029.
  • Ananth CV, Wen SW Trends in fetal growth among singleton gestation in the United States and Canada, 1985 through 1998 Semin Perinatol 2002 26 260–7 doi:10.1053/sper.2002.34772.