Washington: The United States is among the eight countries in the world to experience an increase in maternal mortality since 2003 - joining Afghanistan and countries in Africa and Central America, a study said.
The study ranked the US at 60 in the list of 180 countries on maternal deaths - compared to its rank of 22 in 1990 - demonstrating how it has fallen behind globally.
By contrast, China rose to number 57, up from number 116 in 1990, said researchers from the Institute for Health Metrics and Evaluation (IHME) at University of Washington.
"For American women, high-risk pregnancies and the number of women with inadequate access to preventive and maternal health care are just two potential causes of this trend," explained study author Nicholas Kassebaum, an assistant professor at IHME.
The good news is that most maternal deaths are preventable, and we can do better, he added.
In the US, an average of 18.5 mothers died for every 100,000 live births in 2013, more than double the figures for maternal mortality in Saudi Arabia (7) and Canada (8.2), and more than triple of the figures in Britain (6.1).
The biggest increase in maternal mortality by age group occurred in women who are 20-24 years old.
In 1990, 7.2 women in this age group died for every 100,000 live births and in 2013, 14 died for every 100,000 live births.
The researchers offer a range of possible explanations for the disparities between the US and other countries.
It includes lack of access to prenatal care and other health services, high rates of caesarian section deliveries, and pregnancies complicated by obesity, diabetes, and other conditions.
The vast majority of countries has seen accelerated reductions in maternal mortality - with maternal deaths declining by 2.7 percent per year since 2003, the study added.
The study titled "Global, regional, and national levels and causes of maternal mortality during 1990-2013: a systematic analysis for the Global Burden of Disease Study 2013", was published in the journal The Lancet.