The baby was born healthy and without complication in September, but then its health began to deteriorate rapidly.

Doctors — scrambling to uncover the cause of the infant’s respiratory distress — transferred the baby to the neonatal intensive care unit and began a series of tests, according to a report released this week by the Centers for Disease Control and Prevention. Those tests revealed a deadly blood infection known as late-onset group B Streptococcus agalactiae (GBS) bacteremia, which doctors treated with an 11-day course of antibiotics.

But after returning home, the baby contracted a second GBS infection and was rushed to another hospital. It was there that doctors discovered the cause of the reoccurring infection was the mother’s own placenta.

The woman — who was not identified in the CDC report — had been ingesting her placenta for weeks after registering with a company that processes and encapsulates the organ, which connects the developing fetus to the mother’s uterine wall. While she was ingesting placenta, the woman was also breast-feeding, which transferred the infection from mother to child.

“Three days after the infant’s birth, the mother had received the dehydrated, encapsulated placenta and began ingesting two capsules three times daily,” the CDC stated. The physician instructed the mother to stop consuming the capsules.”

Once the woman stopped, her child — who was given a new round of antibiotics — recovered.

The mother highlighted by the CDC is a single cautionary tale, but a compelling one. Placentas are consumed raw, cooked or dried and turned into powder that is placed in digestible capsules like the kind used by the mother in the CDC case study.

Once a fringe practice, consuming one’s placenta after giving birth has become mainstream in recent years after it was promoted by birthing blogs and celebrities like January Jones and Kim Kardashian, who touted the practice as a way to keep postpartum depression at bay. Proponents of the habit also claim it increases milk production, improves mood and energy levels and offers nutritional fortitude.

There’s only one problem: There isn’t any real evidence to support those alleged benefits, according to the CDC. And the agency’s research on the potential risks of consuming a human placenta is still evolving.

CDC researchers who examined the pills being consumed by the mother discovered that they were full of GBS, a strain that was genetically indistinguishable from the type sickening the infant.

GBS is commonly found in and on adults, but it usually doesn’t cause infections. In newborns with undeveloped immune responses, however, it can wreak havoc. And the strain of GBS found in this case was particularly nasty; it had virulence factors that allowed it to easily slip through the intestinal lining and into the bloodstream — and potentially cross the blood-brain barrier.

One of the risks facing mothers, according to the CDC, is that no standards exist for processing placenta for consumption beyond heating the tissue at 130°F (54°C) for 121 minutes to reduce Salmonella bacterial counts. “The placenta encapsulation process does not per se eradicate infectious pathogens; thus, placenta capsule ingestion should be avoided,” the CDC states. “Clinicians should inquire about a history of placenta ingestion in cases of late-onset GBS infection and educate mothers interested in placenta encapsulation about the potential risks.”

A 2015 study in the Archives of Women’s Mental Health examined all previous studies on eating the afterbirth and found that there is no real evidence to support claims of potential benefits. It also found that there was no research on the potential risks of consuming a human placenta.

The study came about after some patients of study author Crystal Clark  asked her opinion on the practice. Clark is assistant professor of psychiatry and behavioral sciences at Northwestern University Feinberg School of Medicine and a psychiatrist specializing in reproduction-related mood disorders. She told The Washington Post that her patients wanted to know if placental capsules — ostensibly taken to improve their mood — would interact with the antidepressants Clark had prescribed for them.

“I found myself really confused by the question,” Clark said. Neither she nor her colleagues in obstetrics knew of any clinical studies on this.

“Many of my colleagues in obstetrics were more aware of it than I was,” she said. “They’d seen it talked about on TV, so they knew it was happening. But they didn’t think any of their own patients were doing it. That was interesting, since I knew for a fact that some of their patients were considering it.”

Wondering where women were learning about the purported benefits of placentophagy — the term for consumption of the placenta after birth — Clark began reviewing the available literature on the topic. She concluded that there was very little evidence that the practice of ingesting a placenta offers health benefits.

“Of all the studies available, only one showed potential for benefit, and it showed the potential for pain reduction immediately after labor,” Clark said. “But that particular study, although quite rigorous and convincing, suggested that the placenta had to be eaten right after birth, completely, in its entirety, and that it couldn’t be stored or heated. That’s not what human women are doing.”

Placenta-eating remains a popular fad among mothers like Kardashian West, whose tweet about her own experience was retweeted and “liked” thousands of times in 2015.

“I heard so many stories when I was pregnant with North of moms who never ate their placenta with their first baby and then had postpartum depression,” Kardashian West wrote in a blog (well, in her personal app), “but then when they took the pills with their second baby, they did not suffer from depression! So I thought, why not try it? What do I have to lose?”