Nearly one in seven pregnant women will experience a miscarriage. Far less common is the experience of recurrent miscarriage, defined by the American Society of Reproductive Medicine as the involuntary loss of two or more pregnancies before 20 weeks. Fertility specialists at the University of Southern California School of Medicine estimate that just two percent of American women will experience two pregnancy losses in a row; only one percent will have more than three consecutive miscarriages. Rare as it is, the repeated, involuntary loss of pregnancies can be traumatic for women, both physically and emotionally.

Dr. Zev Williams, Director of the Columbia University Fertility Center, tells Brit + Co that pregnancy loss happens in one of two categories: Sporadic losses — typically due to chromosomal abnormalities that result in a non-viable embryo — or losses related to problems with a woman’s reproductive organs or hormones. Issues like uterine polyps and fibroids, inflammation of the uterus, fallopian tube abnormalities, and even thyroid disorders or insulin resistance can prevent embryos from growing properly, which can cause a miscarriage.

“The causes of pregnancy loss are essentially the inverse of all the things that have to go right. There are a huge number of steps that have to occur in order for a pregnancy to succeed, and a roadblock in any one of those can result in recurrent losses,” Williams tells us.

In most cases, losses occur early — often, within the first trimester, and sometimes, sometimes before a woman even knows she’s pregnant — and Williams says the likelihood of miscarriage decreases as pregnancy progresses. “As a woman gets further along, the embryo has been able to overcome more hurdles. If there’s a problem with implanting inside the uterus, the embryo will never get that point,” he says.

No matter the cause, timing, or frequency of recurrent loss, Williams says the experience is often something of an emotional rollercoaster for women trying to conceive. In a study of responses to pregnancy loss, Williams and his colleagues found a wide spectrum of emotional responses.

“Some women [will interpret their] miscarriages as something that wasn’t meant to be, so they’re able to get through it with much less pain,” he says. However, “for about 30 percent of women, a pregnancy loss is almost the equivalent of losing a child — an emotionally devastating event to go through.”

Miscarriage is often painful on its own, but each recurrent miscarriage can be a harsh reminder of previous losses, bringing back painful memories. Williams says many women also blame themselves for not being able to sustain a pregnancy.

“The vast majority of women and couples who experience recurrent loss will look back on the week leading up to the loss and blame themselves,” Williams says. “I often tell patients, ‘We may not know why the losses are happening, but we know why they’re not happening. They have not been due to stress, because you got into an argument, or had a deadline at work.’

In this way, recurrent loss differs from infertility, or not being able to conceive at all. “When an infertile patient gets her first positive test, that’s the greatest moment of joy and excitement for her,” Williams says. “But [for] those who have [experienced] recurrent loss, that moment can be filled with a sense of dread. It’s really not until they’re holding the baby in their arms that they’re able to let their guard down.”

The good news is that most women who suffer from pregnancy loss will eventually deliver a healthy baby. Williams says that after three losses, 64 percent of women go on to have a live birth.

In many cases, it’s as simple as identifying the cause and solution — say, removing polyps from the uterus. Other times, doctors don’t find a cause. “The challenge is finding what’s causing the losses in the first place. Sometimes you just need to wait for the right sperm and egg to come together.”

For anyone who has a friend or loved one experiencing recurrent loss, Williams recommends an empathetic approach. “The key is to try to show understanding and empathy, and not to try to provide solutions,” he says. “Even saying something that seems as natural as ‘Don’t stress so much’ or ‘Try to relax’ can imply that loss happened because someone wasn’t doing those things, which is not the case.”

RELATED: Why We Shouldn’t Be Afraid to Talk About Miscarriage

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