Texas pregnancy-related death rate ranks in the middle of the pack among U.S. states, according to highly awaited federal statistics released Thursday, much lower than was reported four years ago but still slightly higher than the national rate.

The new statistics, the first national data on pregnancy-related deaths in more than a decade, found Texas had the 13th highest rate among 25 states highlighted in a new report on 2018 data, the first year for which comparable numbers were available. Seventy Texas women died while pregnant or within 42 days of delivering for pregnancy-related reasons that year, more than any other state.

“The death of a mother during pregnancy, childbirth or the postpartum period is a tragic loss that has an immeasurable impact on the family, community and society,” said Dr. Carla Ortique, a Texas Children’s Hospital obstetrician and vice-chair of the Texas Maternal Mortality and Morbidity Review Committee. “The CDC's public release of 2018 maternal mortality data is very important … it maintains focus on the unacceptable rate of maternal death in our state and country."

Texas reported 18.5 deaths per 100,000 live births in 2018, according to the National Center for Health Statistics’ new report. That’s about half the rate reported in a 2016 study that turned out to be inflated because of errors on Texas death certificates. The study made headlines around the nation and globe, making it appear Texas had the nation’s worst rate.

A 2018 Texas study found the number of deaths during the period analyzed was less than half that previously reported. But it was still unclear how Texas’ numbers compared with other states.

In fact, according to the report, Kentucky the highest rate, 46 deaths per 100,000 live births, and Illinois has the lowest, 9.7. The South dominated the 25 highlighted states, with eight of the top 12, including Kentucky, Alabama and Oklahoma reporting rates ranging from 41 to 30.

On HoustonChronicle.com: Most pregnancy-related deaths preventable, state report finds

Texas was smack dab in middle, bracketed by 12 states with the higher rates and 12 states with lower rates.

The 2018 national rate for all 50 states was 17.4 deaths per 100,000 live births, according to the report. The report based the national rate on data provided by all 50 states, but only calculated state rates for the 25 states with the highest number of deaths.

A federal goal calls for the nation and states to reduce the number of pregnancy-related deaths to no more than 11.4 per 100,000 live births by 2020.

The NCHS report didn’t provide reasons for the deaths. Previous studies have found hemorrhage and heart issues, often linked to obesity or diabetes, to be the most common causes of pregnancy-related deaths.

Robert Anderson, chief of the mortality branch at NCHS, said there is not enough reliable data before 2018 to analyze trends. He said the evidence suggests the problem isn’t getting worse, as has been perceived to be the case, but added it doesn’t appear to be getting better either.

“That’s something to be concerned about,” said Anderson. “We have maternal mortality data back to 1915 and we have seen dramatic declines since then. But in recent decades the rate has been rather flat in comparison.”

Anderson said the high rates now reflect a greater emphasis on reporting. Electronic death certificates recently began including a checkbox for reasons related to the pregnancy, both during and after. But it took until mid-2017 for all 50 states to roll out the checkbox, which is why the NCHS believes it now has enough uniform data to release stats.

Related: Life-threatening pregnancy complications on the rise in Harris County

It had stopped reporting pregnancy-related deaths after 2009 because of the lack of uniform data among states. Those states that were quick to implement the checkbox reported higher rates than states that missed cases because they hadn’t implemented the checkbox. NCHS’s analysis found a dramatic increase in the number of maternal deaths detected as a result of the checkbox.

But the checkbox has also caused errors. That was the case in Texas, as unwittingly documented in the 2016 study. Researchers who delved into the cases found doctors had clicked on death certificates’ “pregnant at the time of death” option unintentionally, sometimes apparently because that option is located directly below the “not pregnant within the past year” option on the electronic certificate’s drop-down list.

Anderson said follow-up studies with some other states showed such errors as well. He said the NCHS is not entirely sure why such errors are occurring.

“This truly underscores the need for the detailed reviews that are performed by state-based maternal mortality review committees like we have in Texas,” said Dr. Lisa Hollier, a Texas Children’s ob-gyn and the chair of the Texas Maternal Mortality and Morbidity Task Force. “The multidisciplinary committee reviews the clinical information to ensure the accuracy of the data and the maternal mortality rates.”

In all, the report found 658 women died of maternal causes in the U.S. in 2018. The rate was highest in blacks — 37 deaths per 100,000 births, compared to 14.7 for whites and 11.8 for Hispanics — and women aged 40 and older. The latter’s death rate was 81.9, nearly eight times that for women under age 25.

The report did not break down racial/ethnic and age differences at the state level, but previous Texas-specific studies have reported the same trends.

todd.ackerman@chron.com