Here's How a Transgender Woman Breast-Fed for 6 Weeks

A baby breastfeeding.
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A transgender woman was able to produce enough milk to breast-feed her partner's newborn baby for six weeks, according to a new report of the case.

The report is the first in the medical literature to formally document lactation in a transgender woman, the researchers said.

The transgender woman was able to breast-feed after undergoing a regimen of hormonal therapy along with the use of a breast pump, in a process similar to what's done for women who cannot produce breast milk on their own (including women who want to breast-feed after adoption). [Men vs. Women: Our Key Physical Differences Explained]

"We want to present our patients with the full range of reproductive choices, and this is one step closer to that," Dr. Tamar Reisman, an endocrinologist at Mount Sinai hospital's Center for Transgender Medicine and Surgery in New York, told the Washington Post.

The report was published in the January issue of the journal Transgender Health.

It's known that people who are born male can produce milk — for example, men who undergo hormonal treatment for prostate cancer can, in some cases, develop breast fullness and lactate, said Dr. Maurice Garcia, the director of the Transgender Surgery and Health Program at Cedars-Sinai Medical Center in Los Angeles, who was not involved with the case. However, men don't usually lactate much because of the differences in hormone levels between men and women. But the new case shows that this transgender woman produced enough milk to sustain a baby for six weeks, which is "terrific," Garcia said.

The report underscores the anatomic similarity between the sexes, which is greater than many people appreciate, Garcia told Live Science. It's "encouraging that we can build on this anatomic homology between the genetic sexes … to help [transgender people] bring their bodies more in line with their gender."

In the new case, the patient first began taking feminizing hormones in 2011 as part of her gender transition. Then, in 2017, she asked her doctor about the possibility of breast-feeding her partner's baby. Her partner was pregnant at the time, but did not plan on breast-feeding. The transgender woman hoped to be the primary food source for the child, whom she would also adopt, the report said.

The patient underwent a three-month course of treatment, which included the drugs domperidone and the hormones estradiol and progesterone. (Domperidone is a drug that increases levels of prolactin, which aids in lactation. The drug is not approved for use in the United States, and the patient in this case obtained it from Canada.) She also took spironolactone, which blocks testosterone.

The woman breast-fed the baby for six weeks and then began supplementing the breast milk with formula because she was concerned that her milk supply had become insufficient for the child. The baby is currently 6 months old, and is growing and feeding normally, the report said.

More research is needed to optimize treatments for transgender women who want to breast-feed, the report said. For instance, it's not known whether all of the hormones and drugs used in this case were needed to achieve lactation, or whether adjusting the doses could lead to even greater milk production.

Original article on Live Science.

Rachael Rettner

Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.