Suspicion and treatment of the macrosomic fetus: a review.
OBJECTIVE
To review the prevalence of and our ability to identify macrosomic (birthweight >4000 g) fetuses. Additionally, based on the current evidence, propose an algorithm for treatment of suspected macrosomia.


METHODS
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 weights >5000 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 >4000 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 of estimated fetal weight that should prompt cesarean delivery.


CONCLUSIONS
Due to the inaccuracies, among uncomplicated pregnancies suspicion of macrosomia is not an indication for induction or for primary cesarean delivery.
Chauhan
Suneet P
SP
Spartanburg Regional Medical Center, Spartanburg, SC, USA. SChauhan@srhs.com
Grobman
William A
WA
Gherman
Robert A
RA
Chauhan
Vidya B
VB
Chang
Gene
G
Magann
Everett F
EF
Hendrix
Nancy W
NW
D000465:Algorithms; D001720:Birth Injuries / Q000209:etiology; D002585:Cesarean Section; D004420:Dystocia / Q000209:etiology; D005260:Female; D005320:Fetal Macrosomia / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000628:therapy*; D006801:Humans; D007231:Infant, Newborn; D007751:Labor, Induced; D011247:Pregnancy; D011256:Pregnancy Outcome; D011254:Pregnancy in Diabetics / Q000150:complications; D015995:Prevalence; D012680:Sensitivity and Specificity; D014463:Ultrasonography; D014481:United States