Endocrine-related causes and consequences of intrauterine growth retardation.

Abstract

The term intrauterine growth retardation (IUGR) is assigned to newborns born with a birth weight and/or birth length below the tenth percentile for their gestational age. Intrauterine growth retardation is usually due to maternal, fetal factors, or placental insufficiency, while endocrine factors represent just a small minority in its etiology. Main endocrine-related causes of IUGR are disorders in insulin or insulin-like growth factor-I (IGF-I) secretion or action. Newborns with IUGR are at increased risk to develop a metabolic syndrome later in life, namely obesity, arterial hypertension, hypercholesterolemia, cardiovascular disease, impaired glucose tolerance, or diabetes mellitus type 2. This association is the result of the adaptational changes of the fetal endocrine-metabolic mechanisms to the impaired intrauterine milieu to assure survival in the short term. The persistence of these changes after birth can be detrimental in adult life. Furthermore, premature adrenarche, as well as ovarian hyperandrogenism, seem to be associated with IUGR in girls, demonstrating that IUGR may have long-lasting effects on both somatic health and reproductive function. Finally, the intrauterine exposure of the fetus to stressors may affect the individual's ability to face stress in postnatal life. Therefore, if optimization of somatic and psychosocial well-being of the individual is the golden goal of medicine, special attention should be paid to maintain an optimal intrauterine milieu devoid of any stressors with adequate nutrient supply and to reserve ideal psychosocial support to the pregnant woman.