The patient: A woman in upstate New York

The symptoms: About two weeks after her baby's birth, the woman began experiencing intensely negative emotions at every breastfeeding session. These feelings of "extreme unhappiness" would start just before her milk ejection reflex (during which milk moves from the breast ducts to the nipples) and last up to two minutes.

The feelings would end abruptly when she finished breastfeeding and then appear again the next time she was about to release milk, according to a report of the case, which the patient co-authored. The patient was a breastfeeding counselor for the United States Department of Agriculture Women, Infants, and Children (WIC) Program.

Until the baby was about 18 months old, this phenomenon would happen every time the woman breastfed — about five times per day, on average. Unlike postpartum depression,‬ which can cause persistent feelings of despondency, anxiety and mood swings in new parents,‬ the woman felt "helpless, hopeless, [and] worthless" only during her milk release. She reported that she otherwise felt happy and bonded with her new baby.

What happened next: When her baby was 7 months old, the woman began meeting with a lactation consultant, who later co-authored the case report. They worked together to track the mother's symptoms over time, noting when negative feelings began and if any intervention made them subside or worsen.

The diagnosis: Because the woman's condition did not have a formal name at the time, she began calling it "dysphoric milk ejection reflex," or D-MER.

The case report authors initially suspected that fluctuations in the woman's oxytocin levels might be causing D-MER, since the hormone is released into the bloodstream prior to the milk ejection reflex during breastfeeding. However, external factors that are known to affect oxytocin levels, such as tobacco use, did not always trigger the woman's symptoms.

Next, they looked at dopamine. The chemical messenger's fluctuations during breastfeeding are less studied than those of oxytocin and prolactin, another hormone linked to lactation. However, dopamine levels have otherwise been connected to strong emotional responses. Activities that seemed to ease the patient's D-MER symptoms — such as taking the cold medication pseudoephedrine, smoking cigarettes or binging on chocolate ice cream — are also known to increase dopamine levels. Meanwhile, acute stress, which reduces dopamine, worsened her symptoms.

The authors hypothesized that an abrupt drop in dopamine prior to milk release might be a trigger for D-MER.

The treatment: The woman began taking bupropion (better known by the brand name Wellbutrin), an antidepressant that increases the amount of dopamine in the brain. She saw a dramatic reduction in her D-MER symptoms within a day, and five days later, her symptoms were almost entirely gone.

However, she stopped taking the drug after a few weeks due to unwanted side effects (which aren't described in the report), and the symptoms came back. She then tried an herbal remedy containing roseroot (Rhodiola rosea), a plant historically used in some places to manage depression. Some recent studies suggest that compounds in R. rosea interact with receptors for chemical messengers in the brain; however, there is little reliable evidence demonstrating its purported therapeutic benefits, according to the National Center for Complementary and Integrative Health.

She took R. rosea three to four times per day, reporting that her symptoms became "much milder" but returned if she skipped a day. As her daughter grew older and the woman breastfed less often, the woman stopped taking the supplement. When the child was 3 years old and no longer breastfeeding, the woman's D-MER symptoms went away entirely.

What makes the case unique: Prior to this report, published in 2011, D-MER was not widely recognized or documented in the scientific literature, and there was no research into its causes or treatment.

The patient and co-author of the report created the website D-MER.org in 2007 to share information about the condition more widely. She hoped to raise awareness among medical professionals and to help breastfeeding people who experience this condition by providing resources and support and encouraging them to understand that what they were feeling was a physiological side effect of nursing. Since the site's launch, hundreds of visitors have described having negative feelings while breastfeeding, according to the report.

Over the past two decades, more case reports describing the condition have been published. In a 2025 paper in the European Journal of Obstetrics & Gynecology and Reproductive Biology, researchers estimated that roughly 14.2% of lactating parents experience D-MER and that 1 in 6 stop breastfeeding as a result. Dopamine is thought to play a part, but the exact cause of D-MER has not been definitively established in peer-reviewed research yet.

There is no definitive treatment for D-MER, although some have anecdotally found relief through techniques for stress reduction, such as meditation and breathing exercises, and by seeking support from partners, friends and breastfeeding groups online.

Short-lived negative feelings resembling D-MER have also been reported in people who are not lactating. These anecdotal accounts describe intense, negative feelings brought on by nipple stimulation. One online discussion group referred to this phenomenon as "sad nipple syndrome," according to the authors of the case report. As with D-MER, dopamine may play a part, but the overall neurochemistry underlying that emotional response is unknown.

Breastfeeding and parenthood can be an emotional roller coaster even under the best circumstances, the authors noted. In that sense, they explained, people with D-MER have "the same emotional peaks and valleys" as all new parents do. Yet the negative feelings that accompany D-MER are nonetheless different from the normal range of emotions in the parents of newborns, and they can cause extreme distress if they are not correctly identified and addressed as being specific to breastfeeding.

People with D-MER, the authors concluded, "serve as a reminder to us all that we do not yet have a complete understanding of human lactation."

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