This study was published in the Journal of the American Medical Association 2001 Aug 15;286(7):807-14.
Study title and authors:
Exposure to soy-based formula in infancy and endocrinological and reproductive outcomes in young adulthood.
Strom BL, Schinnar R, Ziegler EE, Barnhart KT, Sammel MD, Macones GA, Stallings VA, Drulis JM, Nelson SE, Hanson SA.
University of Pennsylvania, Center for Clinical Epidemiology and Biostatistics, 824 Blockley Hall, 423 Guardian Dr, Philadelphia, PA 19104-6021, USA. bstrom@cceb.med.upenn.edu
This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/11497534
The objective of this study was to examine the association between infant exposure to soy formula and health in young adulthood, with an emphasis on reproductive health. The study included 811 adults aged 20 to 34 years who as infants were fed either soy formula (248) or cow milk formula (563).
The study found:
(a) Women who had been exposed to soy formula as an infant had longer duration of menstrual bleeding compared to the women who had been fed cow milk formula.
(b) Women who had been exposed to soy formula as an infant had a 77% increased risk of suffering with discomfort during their period compared to the women who had been fed cow milk formula.
(c) Women who had been exposed to soy formula as an infant had a 34% increased risk of suffering with breast tenderness compared to the women who had been fed cow milk formula.
(d) Women who had been exposed to soy formula as an infant had a 61% increased risk of been unsuccessful in attempting pregnancy compared to the women who had been fed cow milk formula.
(e) Women who had been exposed to soy formula as an infant had a 111% increased risk of having a preterm delivery compared to the women who had been fed cow milk formula.
The data from the study shows that compared to women who were fad cow milk formula, women who had been exposed to soy formula as an infant have longer and more difficult periods and find it harder to conceive.
