When the man arrived at the hospital with severe abdominal pains, a nurse didn’t consider it an emergency, noting that he was obese and had stopped taking blood pressure medicines. In reality, he was pregnant — a transgender man in labour that was about to end in a stillbirth.

The tragic case, described in Wednesday’s New England Journal of Medicine, points to larger issues about assigning labels or making assumptions in a society increasingly confronting gender variations in sports, entertainment and government. In medicine, there’s a similar danger of missing diseases such as sickle cell and cystic fibrosis that largely affect specific racial groups, the authors write.

“The point is not what’s happened to this particular individual but this is an example of what happens to transgender people interacting with the health care system,” said the lead author, Dr Daphna Stroumsa of the University of Michigan, Ann Arbor.

“He was rightly classified as a man” in the medical records and appears masculine, Stroumsa said. “But that classification threw us off from considering his actual medical needs.”

Stroumsa would not say where or when the case occurred, and the patient was not identified.

Transgender men, who are considered female at birth but who identify as male, may or may not be using masculinizing hormones or have had surgical alterations, such as womb removal.

The 32-year-old patient told the nurse he was transgender when he arrived at the emergency room and his electronic medical record listed him as male. He hadn’t had a period in several years and had been taking testosterone, a hormone that has masculinizing effects and can decrease ovulation and menstruation. But he quit taking the hormone and blood pressure medication after he lost insurance.

A home pregnancy test was positive and he said he had “peed himself” — a possible sign of ruptured membranes and labour. A nurse ordered a pregnancy test but considered him stable and his problems non-urgent.

Several hours later, a doctor evaluated him and the hospital test confirmed pregnancy. An ultrasound showed unclear signs of fetal heart activity, and an exam revealed that part of the umbilical cord had slipped into the birth canal. Doctors prepared to do an emergency cesarean delivery, but in the operating room, no fetal heartbeat was heard. Moments later, the man delivered a stillborn baby.

“It’s a very upsetting incident, it’s a tragic outcome,” said Dr Tamara Wexler, a hormone specialist at NYU Langone Medical Center.

“Medical training should include exposure to transgender patients” so health workers are better able to meet their needs, Wexler said. “A lot of doctors who are practising didn’t have that in their training” but can still learn from such patients now.

Nic Rider, a transgender health specialist and psychologist at the University of Minnesota, said training isn’t enough.

“There are implicit biases that need to be addressed,” Rider said.

Health records may use male/female templates for gender but “it doesn’t mean that we just throw out critical thinking or think about how humans are diverse,” Rider said.

The case is horrifying but “not terribly surprising,” said Gillian Branstetter, a spokeswoman for an advocacy group, the National Center for Transgender Equality in Washington.

Transgender people often run into problems getting gender-specific health care such as cervical cancer screening, birth control and prostate cancer screenings.

More needs to be done to improve medical awareness and recognition of diversity because “the consequences can be so dire, as this case shows,” Branstetter said.