Every year in the United States about 1 million pregnancies end in a miscarriage and in as many as half of those cases doctors are at a loss to explain why they happened.

Experts say stigma and shame are hampering efforts to learn more

about what causes miscarriages. Newsera deputy senior producer Courtney Norris looked

into this for a very personal reason. As many as one in four pregnancies

in America will end in a miscarriage but we still know little about why. I

experienced this firsthand when I miscarried earlier this year, doctors couldn't give me a reason.

Experts say research on the issue is lagging.

It is by far the most common complication of pregnancy, yet most people think it's very rare.

And a big part of that is there is such a reluctance to even speak about it.

I turn to experts like Dr. Zev Williams with Columbia University's

Irving Medical Center and Dr. Diana Bianchi, the director of the National

Institute of Child Health and Human Development.

What's different about miscarriage is the guilt factor,

you know, why couldn't I continue this pregnancy in my former practice.

People came up with all kinds of explanations

why they lost the pregnancy,

and probably none of them were true.

One problem in miscarriage research is the stigma that comes with the loss.

Dr. Asima Maud is an OOGYN who herself miscarried.

All of us end up blaming ourselves.

I did that myself and I am a specialist in this field, but most of the time it's not your fault. It's not something you did. There are other reasons for pregnancy loss, but the majority are genetic and you don't have control over that.

While most miscarriages occur due to chromosomal abnormalities, little is known about other

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