The expert opinion
Panicked without much justification, it turns out. Because so many factors go into successful breastfeeding, such as the infant's muscle mechanics and the mother's anatomy to name just two, identifying nipple confusion is a difficult task and only a handful of scientific studies are relevant.
A comprehensive paper, published in Newborn and Infant Nursing Reviews, examined all previous research and declared that the jury is still out whether the phenomenon of nipple confusion even exists. The authors advised health care providers to take "a more moderate position" on bottle-feeding a breastfed infant.
A recent study that looked at bottles and pacifiers -- another supposed "nipple-confusing" item that parents are told to avoid -- found that neither caused "early breastfeeding problems." What the study did find: Early bottles and pacifiers may shorten the overall length of time that a woman ends up breastfeeding, though it's not clear why. "The exact reason women stop breastfeeding sooner isn't known," says Dr. Neifert. "Women who are using bottles and pacifiers may be having trouble nursing already or may have a lower motivation to continue it." On the flip side, she adds, the flexibility of pumping and bottle-feeding can allow working moms to continue breastfeeding longer than they would have otherwise.