Generally, a normal baby weighs about 3.4 kg. If the baby's weight is more than 4 kg, then, it can lead to serious complications to mother as well as the foetus. This abnormal condition having higher weight of baby is called as fetal macrosomia. Diabetes that is poorly controlled in pregnancy is the greatest risk factor for fetal macrosomia. It is also caused due to elevated maternal plasma glucose levels and resulting elevated insulin and insulin like growth factor levels, which stimulate glycogen synthesis, fat deposition, and fetal growth.
Infants with a birth weight of 4000 g (8 lb 13 oz) or more comprise up to 10% of infants born in the United States, and, in 1998, 1.5% of all neonates had a birth weight equal to or greater than 4500 g (9 lb 15 oz).
This can be determined preliminary through excessive maternal weight gain, congenital anomalies, etc. Research has been started in United Kingdom to control gestational diabetes in pregnant women. For this, drugs have been developed.