Macrosomia
Condition
(Large for Gestational Age; LGA)
Definition
Macrosomia is when a baby is larger than normal before birth. Most babies are about 7 pounds (3.17 kilograms). Babies with this health problem are 8 pounds, 13 ounces (3.99 kilograms) or more.
Causes
The most common cause is diabetes in the mother during pregnancy.
Risk Factors
Things that may raise the risk are:
- Mother having diabetes or gestational diabetes
- Mother is obese
- Mother and/or father of large size
- Too much weight gain by the mother during pregnancy
Symptoms
The main sign is a predicted birth weight of at least 8 pounds, 13 ounces or more.
Diagnosis
The doctor will ask about your symptoms and health history. A physical and pelvic exam will be done.
Pictures may be taken to estimate the birth weight. This can be done with ultrasound.
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Treatment
The goal of treatment is to safely deliver the baby. The baby may be too large to be delivered through the birth canal. A Cesarean delivery (C-section) may be done.
Prevention
To lower the risk of this problem:
- Get early prenatal care.
- Maintain a healthy weight during pregnancy.
- Manage diabetes.
American Congress of Obstetricians and Gynecologists
Centers for Disease Control and Prevention
CANADIAN RESOURCES:
Women's Health Matters
Society of Obstetricians and Gynaecologists of Canada
American Congress of Obstetricians and Gynecologists
Centers for Disease Control and Prevention
CANADIAN RESOURCES:
Women's Health Matters
Society of Obstetricians and Gynaecologists of Canada
References
- American College of Obstetricians and Gynecologists Committee on Practice Bulletins—Obstetrics. Practice Bulletin No. 190: Gestational Diabetes Mellitus. Obstet Gynecol. 2018 Feb;131(2):e49-e64, reaffirmed 2019.
- Gestational diabetes mellitus (GDM). EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/gestational-diabetes-mellitus-gdm. Updated July 13, 2018. Accessed August 7, 2018.
- 6/16/2015: DynaMed Systematic Literature Surveillance https://www.dynamed.com/condition/gestational-diabetes-mellitus-gdm: Wiebe HW, Boulé NG, et al. The effect of supervised prenatal exercise on fetal growth: a meta-analysis. Obstet Gynecol. 2015 May;125(5):1185-1194.
Contributors
- Elliot M. Levine, MD, FACOG
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