Dr. Amy Evans, a pediatrician and medical director of the Center for BreastfeedingMedicine in Fresno, California, says that as many as 5% of all women have underlying medical conditions that prevent or seriously hinder lactation: hypoplasia, thyroid problems, hormonal imbalances and insufficient glandular tissue, among others.
"This study goes against everything that's been published for several years now from very reliable clinicians and researchers about the potential hazards of supplementing exclusively breast-feeding babies with formula, " says Dr. Kathleen Marinelli, an associate professor of pediatrics at the University of Connecticut School of Medicine and the chair-elect of the U.S. Breastfeeding Committee.