The importance of infections of the pregnant woman as causes of low birth weight of infants in industralized societies has been indicated in a number of studies. These infections have included upper-respiratory tract and systemic infections, bacterial infections of the urinary tract, and genital mycoplasmal infections.1,2
Specific perinatal infections such as rubella, cytomegalovirus, and Toxoplasma are known to be associated with higher rates of low-birth-weight infants.
MATERIALS AND METHODS
The Collaborative Perinatal Study was a prospective investigation of approximately 60,000 pregnancies at 12 university-affiliated institutions throughout the United States. It consisted of detailed examinations of mothers during pregnancies, observation of the children from birth through 7 to 8 years of age, and collection of cord serum and serial serum specimens from the mothers from the time of registration until six weeks postpartum.Serum specimens from women who delivered low-birth-weight infants and from matched controls, selected on the basis of