The condition strikes as many as 30% of all twin or multiple pregnancies. 

Teen Mom OG star Taylor Selfridge recently revealed that she and fellow reality star Cory Wharton have suffered a pregnancy loss. But she didn't have a miscarriage—it was the result of a condition called vanishing twin syndrome.

“I’m doing just fine. I’m happy, healthy, our baby is healthy,” the expectant mother, who is 19 weeks into her pregnancy, wrote on an Instagram story on November 27, per Us Weekly. “A few days after the announcement, we found out we were supposed to actually have twins, I ended up losing one of them.”

After sharing her tragic news, many mislabeled her loss, according to the 25-year-old. “I don’t like that people are calling it a miscarriage now,” she told Us Weekly. “It’s called vanishing twin syndrome or disappearing twin syndrome.”

She explains that she and Wharton went in for a routine prenatal checkup, and doctors “found a separate empty sac so we didn’t know that we had twins before that.”

“I was so stressed out during the first trimester that I was afraid it was my fault that happened and that’s what I struggle with now,” she continued. “Our baby is very healthy, we have no genetic issues to worry about after testing and we’re very happy about that.”  

What exactly is vanishing twin syndrome? 

According to the American Pregnancy Association, vanishing twin syndrome affects 21-30% of multifetal pregnancies. It occurs when “a twin or multiple disappears in the uterus during pregnancy as a result of a miscarriage of one twin or multiple.” It often goes unnoticed because the fetal tissue is absorbed by the other twin, a multiple, the placenta or the mother, giving the appearance of a “vanishing twin.”

Until ultrasounds became readily available, doctors weren’t able to diagnose the death of a twin or multiple until after childbirth. However, with today’s technology, doctors can detect multiple fetuses during the first trimester.

In some cases such as Selfridge’s, a woman may not know she is carrying twins, because the loss occurs before the multiple’s heartbeat or embryo is detected by doctors. In other cases, a woman might be informed she is carrying twins, then learns about the loss at a future appointment. Some women will also experience miscarriage symptoms, such as bleeding, cramping, and pelvic pain.

Similar to miscarriage, the cause of vanishing twin syndrome is generally unknown, but analysis of fetal tissue often points to chromosomal abnormalities.

If the loss occurs in the first trimester, there are generally no signs or symptoms in the mother or surviving fetuses, and no supplementary medical care is needed. However, if the loss occurs later in the pregnancy, increased risks can include a higher rate of cerebral palsy for the remaining fetus.

To get our top stories delivered to your inbox, sign up for the Healthy Living newsletter