(Reuters Health) - State laws restricting access to family planning and abortion are contributing to rising rates of pregnancy-related deaths in the United States, researchers say.

The chief contributors, they reported this week in the American Journal of Preventive Medicine, are laws and fiscal restrictions that result in closures of Planned Parenthood clinics and laws restricting abortions to very early in pregnancies, often before many women know they are pregnant.

The United States has the highest rate of pregnancy-related deaths in the developed world, with some 700 women dying each year from pregnancy complications, according to the Centers for Disease Control and Prevention.

Most of those deaths - three out of five - could have been prevented, the CDC reported earlier this year. Chief causes of maternal death include heart disease and stroke, followed by infections and severe bleeding.

U.S. death rates from pregnancy are 3 to 4 times higher for black women than for white or Hispanic women.

“Maternal mortality is a very serious issue in the United States. Having a baby is not supposed to be a fatal experience, yet when you compare the rate of death in American women giving birth compared to other developed countries, the rate is much higher,” study co-author Christopher (Kit) Baum, a professor of economics and social work at Boston College, said in a telephone interview.

Baum and colleagues studied death certificates issued from 2007 to 2015 in 38 states. Deaths were deemed pregnancy-related if they occurred during childbirth or within 42 days of giving birth.

During that time, there were 4,767 deaths among women up to age 44 and 26.5 million live births, or an overall maternal death rate of 17.9 per 100,000 live births. Death rates varied from 7.6 per 100,000 live births in Nevada to 33.3 per 100,000 live births in the District of Columbia. For black women, the rate was 39.9 per 100,000 live births, about three times higher than for white or Hispanic women.

The researchers used the data to model the impact of state initiatives to limit access to family planning clinics and abortions.

They estimate that reducing the number of Planned Parenthood clinics in a state by 20% could result in an 8% increase in maternal deaths.

“The closure of Planned Parenthood Clinics had a very significant effect on maternal deaths,” Baum said, adding that such clinics provide prenatal care that can help identify risky pregnancies and treat women before they give birth.

The study also estimated that laws restricting abortions to early in the pregnancy had the effect of increasing pregnancy-related deaths by 38%.

“This had a huge effect on the material mortality rate,” Baum said.

Several states have passed “heartbeat” laws that restrict abortions to the period before a fetal heartbeat can be detected, which can occur as early as six weeks into a pregnancy.

One recent example is a measure in Ohio that was slated to take effect on July 11, but a federal judge blocked it after the American Civil Liberties Union and Planned Parenthood sued. Both groups said the law could end 90% of abortions in the state.

“This study validates what all of us who work on the frontlines to support mothers see with our own eyes every day: reproductive health and maternal health are inseparable. It is not at all surprising that states that restrict access to contraception, abortion, and other forms of critical reproductive health services also experience higher rates of maternal mortality,” said Dr. Neel Shah, an obstetrician-gynecologist at Harvard’s Beth Israel Deaconess Medical Center in Boston.

Limits of the study include the fact that not all states use the same criteria to gather data on maternal deaths, preventing the researchers from looking at other factors that might affect maternal health.

“We cannot conclude from the methodology what the specific causes of the increased deaths are but we can say with confidence that states that provide less health services are significantly more dangerous places to be a mother,” Shah said in comments emailed to Reuters.

SOURCE: bit.ly/2S8RtO5 American Journal of Preventive Medicine, online December 16, 2019.