An infant whose weight is below the 10th percentile for gestational age at birth. Although the overall size of the infant is small, the organ systems are mature for age.
Several factors can cause delayed growth of a fetus.
Undernutrition of the fetus may occur as a result of insufficiency of the placenta, multiple pregnancies, heart disease in the mother, preeclampsia or eclampsia , and high altitude. Babies with congenital anomalies are often associated with a below-normal birth weight. Infections during pregnancy that affect the fetus, such as rubella , cytomegalovirus, toxoplasmosis and syphilis , may also affect the birth weight. Risk factors in the mother that may contribute to intrauterine growth retardation include multiple gestation , poor nutrition, heart disease or high blood pressure , smoking , drug addiction , alcohol abuse . Newborn physical examination shows weight below the 10th percentile for age.