Individualized fetal growth curves can be used to assess the appropriateness of fetal growth given the nonpathological characteristics or predict size at birth given all growth-determining characteristics of the pregnancy. Fetal growth may be affected by the mother's nutrition throughout her life. In developed countries, adequate micronutrition before conception and avoidance of teratogens in early pregnancy are the nutritional factors most relevant to optimal fetal growth. Under famine or near-famine conditions, fetal growth appears increasingly restrained by a lack of maternal energy supply as pregnancy progresses. In the developed world, the major causes of fetal growth pathology are maternal vascular disease, particularly preeclampsia, maternal infections, particularly of the genitourinary tract, chromosomal and genetic anomalies, and, increasingly, syndrome X, the metabolic anomaly that includes diabetes and insulin resistance. There is some evidence that these may respond to micronutritional therapy.