Concentration of fat, protein, lactose and energy in milk of mothers using hormonal contraceptives.

ABSTRACT

PIP: Researchers compared data on 22 women using either a barrier method or a natural family planning method or had undergone female sterilization (controls) with data on 89 women using either a low dose combined oral contraceptive (OC), a medium dose combined OC, a low dose progestin only OC, the injectable Depo-Provera, or an IUD to examine the hormonal contraceptives' effects on the concentration of total protein, lipids, lactose, and energy in human milk. They recruited the women from private and public family planning clinics in Brasilia, Brazil between 1984 and 1987. The mean stages of lactation were 15 weeks for controls, 17 weeks for women using the combined low dose OC, 5 weeks for those using the combined medium dose OC, 5 weeks for those using the combined medium dose OC, 9 weeks for those using the low dose progestin only OC, 5 weeks for those using Depo-Provera, and 9 weeks for those using the IUD. Almost all the concentrations of total protein, lipids, lactose, and energy both before and after contraceptive therapy fell within the range for healthy women. The mean value of total protein in women using Depo-Provera was the only value higher than that range. The low dose OC was associated with a considerable increase in fat (3 g/dL vs. 4.8 g/dL; p=.035). Women taking the medium dose OC experienced a significant decrease in lactose (6.8 g/dL vs. 7.25 g.dL; p=.004). The time between last nursing and milk sample collection (nursing interval) caused considerable variation in fat (p=.03) and total energy (p=.02) in those samples collected before contraceptive therapy. When the researchers adjusted the data for stage of lactation and nursing interval from all 6 groups, the contraceptives had no significant effect on total protein, lipids, lactose, and energy.