Effects of Infant Diets on Estrogen Activity and Development

Inclusion Criteria

• •Full term infants defined as age 37-41 weeks gestational age at birth. Ultrasound evidence or reliable reporting of last menstrual period (LMP) by infant's mother.
• •Can be categorized into one of the feeding definitions:
• •Breastmilk Category:
• •0-48 hours old (Age-Interval: 1) - Breastmilk exclusively;
• •49 hours - 3 months (Age-Interval: SEAD1 = 2 through 7) - Breastmilk exclusively;
• •Greater than 3 months (Age-Interval: SEAD1 = 8 through 19) - Breastmilk exclusively OR Breastmilk and Cow-based formula.
• •Restriction: Babies in the Breastmilk category are not allowed to have had any SOY foods including SOY formula and solid foods containing SOY in their lifetime.
• •Cow-Based Formula Category:
• •0-48 hours old (Age-Interval: 1) - Cow-based formula exclusively;
• •49 hours - 3 months (Age-Interval: SEAD1 = 2 through 7) - Cow-based formula exclusively;
• •Greater than 3 months (Age-Interval: SEAD1 = 8 through 19) - Cow-based formula exclusively.
• •Exception: If a baby was Breastfed in the nursery, the baby must have gone home on Cow-based formula and have been on Cow-based formula exclusively ever since. Such a child cannot participate in the SEAD study until s/he has been exclusively Cow-based formula fed for at last 2 weeks.
• •Restriction: Babies in the Cow-based formula category are not allowed to have had any SOY foods including SOY formula and solid foods containing SOY in their lifetime.
• •Soy Formula Category:
• •0-48 hours old (Age-Interval: 1) - Soy formula exclusively;
• •49 hours - 3 months (Age-Interval: SEAD1 = 2 through 7) - Soy formula exclusively;
• •Greater than 3 months (Age-Interval: SEAD1 = 8 through 19) - 2/3 of lifetime on Soy formula exclusively \& continuously, and including the two weeks up to the exam.
• •Exception: If a baby was fed something other than Soy formula in the nursery, the baby must have gone home on Soy and been on Soy exclusively ever since. Such a child cannot participate in the SEAD study until s/he has been exclusively Soy-fed for at least 2 weeks.
• •Birth weight between 2501 - 4499 grams.
• •Age 0-12 months for girls and age 0-6 months for boys.