Hormone therapy to induce lactation generally consists of taking estrogen to simulate the high-estrogen state of pregnancy. The estrogen is then abruptly stopped to mimic the rapid hormonal changes following delivery. A course of a prolactin-enhancing drug such as metaclopromide (Reglan) is then instituted. Sucking stimulation (with a pump or by baby) is begun at this point.
Milk production typically begins between one to four weeks after initiating mechanical stimulation. A 1994 study of induced lactation using medications, published in The Journal of Tropical Pediatrics, describes onset of milk production between five and 13 days. (See abstract at the end of this article.) This is similar to cases of inductions using only nipple stimulation. At first, the mother may see only drops. During the time that milk production is building, she may notice changes in the color of the nipples and areolar tissue. Breasts may become tender and fuller. Some women report increased thirst and changes in their menstrual cycles or libidos.
Is Induced Milk Adequate for Infant Growth?
Is human milk produced this way adequate for infant growth? The same 1994 study observed babies of mothers inducing lactation in New Guinea, and 89 percent were found to be well nourished at follow-up.
Another study, "Protein Values of Milk Samples from Mothers without Biological Pregnancies," done in 1980 by R. Kleinman and reported in The Journal of Pediatrics, looked at the chemical composition of milk produced by non-biological mothers. Two of the studied women had previously delivered babies; three had never been pregnant. Milk samples were collected from five women with adopted infants who had induced lactation by infant sucking. Milk production (at various levels) was established within 11 days without medication.
Milk samples were collected during the first five days of milk production and compared with samples of milk from five biological mothers. The mean protein concentration in the induced lactating women was identical to that of transitional milk of post-partum donors. There were differences in the concentration of albumin, the antibody immunoglobulin A, and lactalbumin concentrations in the milk produced during the days immediately following birth. Levels of these constituents were higher in the colostrum of the biological mothers. Sucking alone is apparently not sufficient to produce colostrum; other hormonal influences associated with pregnancy seem to be involved. The milk brought in by non-biological mothers, in other words, skips the colostral phase and more closely resembles transitional and mature breast milk. Kleinman's study does not look at other nutritional characteristics (such as fats, carbohydrates, or micronutrients).