The Fetal Origins of Disease and Associations With Low Birthweight

Abstract

After completing this article, readers should be able to: 1. Explain the fetal insulin hypothesis. 2. Explain the thrifty phenotype hypothesis. The importance of the early environment for long-term health has been recognized for many years. Seventy years ago, observations in England, Scotland, and Sweden showed that death rates decreased between 1751 and 1930 due to improved childhood living conditions. Death rates in specific age groups at any time depended more on the date of birth of the individuals than the year under consideration. A relationship between infant mortality and ischemic heart disease in the same geographic cohort of Norwegians was reported in the 1970s. There was a positive correlation between death rates from heart disease and geographic variations in past infant mortality rates. A study in the United Kingdom by Williams and colleagues showed similar findings. These relationships were linked to events in childhood and adolescence. A study by Wadsworth and associates in 1985 revealed that adult blood pressure was inversely related to birthweight in British men and women, which was linked to “social and familial factors, smoking, and body mass.” In 1986, Barker and Osmond examined mortality rates from stroke and cardiovascular diseases in different areas of England and Wales. They noticed a parallel relationship between neonatal mortality in the 1920s and 1930s and the mortality rates from strokes and cardiovascular diseases in the 1960s and 1970s from the same geographic areas. In the early 20th century, a high neonatal mortality rate was an indication of a high occurrence of low-birthweight babies and of poor nutrition and health of the mothers. Barker and Osmond concluded that the health of the mothers was important in determining the risk of stroke in their offspring and proposed that cardiovascular diseases might originate during fetal life or early childhood. To follow up these findings, …