AUSTIN (AP) — Researchers say drug overdoses were the leading cause of maternal deaths in Texas between 2012 and 2015, with opioids to blame for the majority of those.

A report Monday by a state task force blamed 64 maternal deaths occurring up to a year after giving birth on overdoses from 2012-2015, or 17 percent of total deaths. Opioids caused 58 percent of them.

READ MORE: Carroll ISD Parents Pack School Board Meeting Following Administrator's Secretly-Recorded Holocaust Comment

(credit: Getty Images)

A 2016 study found that Texas’ maternal morality rate more than doubled between 2010 and 2012, becoming the highest in the developed world. But state researchers have since said that miscalculations inflated those previous findings.

READ MORE: Police From All Over Rally To Lift Spirits Of North Texas Child Battling Cancer

The task force logged 382 maternal deaths from 2012 to 2015, finding that 38 percent were pregnancy related and 56 percent were associated with pregnancy.

Cardiac events caused 55 deaths and infection/sepsis 32.

MORE NEWS: 1-Year-Old Dallas Boy At Center Of Amber Alert Found Safe

(© Copyright 2018 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)