The effects of oral contraceptive use on iron and copper concentrations in breast milk

Breastfeeding: benefits, risks and alternatives

Obstetricians play a major role in guiding the infant feeding choices of their pregnant patients. The world literature continues to swell with reports and studies of the short- and long-term benefits to both mother and infant of breastfeeding. These benefits include protection against acute illnesses, long-term health protection, the psychological relationship and even savings in health care costs.

Iron and copper in human milk

The reported concentrations of iron and copper in breast milk show a wide variation. Research published over the past 50 y has reported median values of 0.47 and 0.32 mg/L for iron and copper, respectively. The levels of both metals decrease with the progress of lactation. The calculated iron-to-copper ratio of reported means differs from 0.25 to 6.29 (median = 1.18). Maternal constitutional variables such as undernutrition, iron and copper body reserves, stage of lactation, adolescent motherhood, gestation length, and infection and environmental variables such as iron and copper dietary intake, in addition to supplementation, smoking, vegetarianism, and prolonged use of hormonal contraceptives before and during lactation did not consistently affect the concentrations of iron and copper in breast milk. Extreme cases of either low or high levels of body metal availability or altered metabolism due to chelating therapy or illnesses such as Wilson's disease and infections did not affect metal transfer from blood serum to breast milk. There is no clinical or scientific support for the need of extra iron or copper, besides the quantities provided by milk in the full-term breast-fed infant, at least during the first 6 mo.