Estimate birth weight Diabetes mellitus Induction

Objective: To review the prevalence of and our ability to identify macrosomic (birthweight O4000 g) fetuses. Additionally, based on the current evidence, propose an algorithm for treatment of suspected macrosomia. Study design: A review. Results: According to the National Vital Statistics, in the United States, the prevalence of newborns weighing at least 4000 g has decreased by 10 % in seven years (10.2 % in 1996 and 9.2% in 2002) and 19 % for newborns with weightsO5000 g (0.16 % and 0.13%, respectively). Bayesian calculations indicates that the posttest probability of detecting a macrosomic fetus in an uncomplicated pregnancy is variable, ranging from 15 % to 79 % with sonographic estimates of birth weight, and 40 to 52 % with clinical estimates. Among diabetic patients the post-test probability of identifying a newborn weighing O4000 g clinically and sonographically is over 60%. Among uncomplicated pregnancies, there is sufficient evidence that suspected macrosomia is not an indication for induction or for primary cesarean delivery. For pregnancies complicated by diabetes, with a prior cesarean delivery or shoulder dystocia, delivery of a macrosomic fetus increases the rate of complications, but there is insufficient evidence about the threshold o