Macrosomia refers to a very large body size. It is often used to describe an oversized fetus.
The most common cause of macrosomia is diabetes in the mother. Macrosomia can lead to injury during birth and a greater chance of a cesarean delivery (C-section).
Kintanar TA. Obstetric ultrasound. In: Fowler GC, ed. Pfenninger and Fowler's Procedures for Primary Care. 4th ed. Philadelphia, PA: Elsevier; 2020:chap 142.
Putra M, Hobbins JC. Obstetric ultrasound: dating, imaging, and growth. In: Landon MB, Galan HL, Jauniaux ERM, et al, eds. Gabbe's Obstetrics: Normal and Problem Pregnancies. 9th ed. Philadelphia, PA: Elsevier; 2025:chap 9.
Weiner MR, Gurevich P, Shinwell ES, Yogev Y. Pregnancy complicated by diabetes mellitus. In: Martin RJ, Fanaroff AA, eds. Fanaroff and Martin's Neonatal-Perinatal Medicine. 12th ed. Philadelphia, PA: Elsevier; 2025:chap 17.