The U.S. sees more than 21,000 stillbirths a year, new CDC report shows. Here's what to know about the pregnancy complication, and why it's still so prevalent.

Stillbirth is a devastating potential outcome of pregnancy and, unfortunately, progress at reducing them has stalled. A new report from the Centers for Disease Control and Prevention's (CDC) National Center for Health Statistics found that stillbirth rates increased slightly in 2020 and stayed consistently elevated the next year.

In 2021, more than 21,000 stillbirths (or nearly six for every 1,000 pregnancies that lasted 20 weeks or longer) were reported. While that's an improvement from rates in 1990, when there were about 7.5 stillbirths per 1,000 pregnancies at 20 weeks or later, the rate has consistently been around 5.7 since 2019.

Stillbirth is largely misunderstood in the U.S. Here's what you need to know about the tragic pregnancy complication.

What is stillbirth?

Stillbirth is the death or loss of a baby before or during delivery, according to the CDC. Like miscarriage, stillbirth refers to a pregnancy loss. However, stillbirth is usually defined as the loss of a baby at or after 20 weeks of pregnancy.

Stillbirth is broken into three groups: early, late and term. An early stillbirth occurs between 20 and 27 weeks, a late stillbirth happens between 28 and 36 weeks and a term stillbirth happens between 37 or more weeks of pregnancy, per the CDC.

"It can be utterly devastating for families to suffer a stillbirth," Dr. Kjersti Aagaard, professor of obstetrics and gynecology at Baylor College of Medicine, tells Yahoo Life. "The entire family grieves. Pregnancy is a time of joy and celebration of new life, and anticipating the joy of a newborn and their life ahead. With stillbirth, that changes in minutes and takes months, years and even a lifetime to reconcile."

Stillbirth can also impact family dynamics. "The loss may impact relationships and result in lasting emotional impact," Dr. Silvana Ribaudo, an OB-GYN at NewYork-Presbyterian/Columbia University Irving Medical Center, tells Yahoo Life. "Every family's experience is unique, and it is vital to provide support, understanding and resources to families affected by stillbirth as they develop coping strategies and find ways to honor their child's memory."

Stillbirth can have a lasting effect on mental health. "Studies show it can trigger or worsen anxiety, depression and stress and the negative psychological effects can spill into future pregnancies," women's health expert Dr. Jennifer Wider, tells Yahoo Life.

What are the statistics?

About 21,000 babies are stillborn in the United States each year, per CDC data. According to the CDC's data for 2021, fetal mortality rates were highest for females under the age of 15 and aged 40 and above, women who smoked during their pregnancy and women with multiple gestation pregnancies. Black women were also found to be most at risk of a stillbirth, with a 2021 fetal mortality rate of 9.89 stillbirths for every 1,000 pregnancies lasting 20 weeks or longer.

Why is stillbirth so prevalent in the U.S.?

It's not entirely clear. "One in three times, the cause of stillbirth is unexplained," Dr. Christine Greves, a board-certified OB-GYN at the Winnie Palmer Hospital for Women and Babies, tells Yahoo Life. But there are also certain factors that can raise the risk of stillbirth. According to the CDC, those include:

• being 35 years or up

• having low socioeconomic status

• smoking cigarettes during pregnancy

• having certain medical conditions, including high blood pressure, diabetes and obesity

• having multiple pregnancies like triplets or quadruplets

• having had a previous pregnancy loss

Obesity rates have increased in the U.S., and more moms are giving birth at a later age, Greves points out. But she says it's difficult to pin the prevalence of stillbirth to that.

Aagaard notes that late- and near-term stillbirth rates have dropped dramatically in the past 30 years. "We believe that this improvement in term stillbirths is a reflection of being able to monitor babies in the outpatient care setting in pregnancies at risk for stillbirth, and also crucial clinical trials which have shown a benefit to delivering at or near your due date," she says.

"However, despite these advances, the rate of early stillbirth has remained about the same over time," Aagaard adds. "This is due, at least in part, to the risk of stillbirth with major genetic anomalies — like Trisomy 13 or 18 — and with structural genetic variations, such as large duplications or deletions in a single chromosome, as detected by chromosomal microarray testing."

What is Congress doing about it?

This month, the bipartisan, bicameral Maternal and Child Health Stillbirth Prevention Act of 2023 was introduced in the Senate. U.S. Rep. Ashley Hinson noted in a press release announcing the act that there is a "silent crisis" of stillbirth in the country.

The proposed legislation suggests that 25% of stillbirths may be preventable, and notes that improved access to maternal care, especially in rural areas where access to an OB-GYN may be limited, is vital to preventing stillbirths. It also can reduce maternal mortality in the U.S., which is currently the highest of all developed nations in the world.

The bill would allow some federal funding that is already set aside for mothers and children via the Title V, the Maternal and Child Health Services Block Grant of the Social Security Act to be used for prevention of stillbirth. That includes programs that encourage expectant parents to be more aware of and track their babies’ movements in utero.

The bill was submitted last year, but wasn't passed. It's now being resubmitted, but it's unclear if it will fare better this time around.

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