The number of women dying in pregnancy and childbirth has fallen by more than a third since 2000, according to new UN figures, but the rate of decline remains way off track to meet global targets to cut maternal deaths.

In the US maternal death rates have increased by over 50% and progress in reducing deaths in the 10 countries with the highest rates has slowed since 2000.

Figures published on Thursday show that in 2017 an estimated 295,000 women died from complications in pregnancy and childbirth, compared with 451,000 at the turn of the century. Globally, the maternal mortality ratio – the number of deaths per 100,000 live births – now stands at 211, compared with 342 in 2000.

While the decrease was welcomed, there are concerns that the slow pace of change means reaching the target in the UN sustainable development goals (SDGs) of no more than 70 deaths per 100,000 live births by 2030, would be unlikely.

The pace of decline since 2015, when the SDGs were agreed, has been particularly slow.

Poverty, inadequate and sometimes expensive health services and a lack of political will are among the main reasons for the deaths, which are often preventable with the right care.

Anneka Knutsson, chief of the UN population fund (UNFPA) sexual and reproductive branch, said: “Although it’s true that more women and children are surviving today, the slight decrease in maternal deaths between 2015 and 2017 is deeply concerning.”

The new statistics, she said, suggested the SDG target would not be reached “unless we dramatically increase and accelerate our efforts to improve maternal health care by bolstering overall sexual and reproductive healthcare”.

“I think this new statistic should alarm us all,” she said. “Also, the new number hides the fact that huge inequalities still exist between and within countries. We also know that lack of quality care is a major killer. We simply must do better. We need to be accountable.”

The figures, published by the World Health Organization, the UNFPA, the UN children’s agency (Unicef) the World Bank and the UN Population Division, are based on data collated from countries with populations of more than 100,000, plus Puerto Rico and the West Bank and Gaza.

The UN said collecting accurate data remained a challenge in countries with inadequate reporting systems, which means the actual figures are likely to be higher.

Two-thirds of deaths still occur in sub-Saharan Africa. In 2017, the estimated number of deaths in the region was 196,000, compared with 201,000 in 2015. In Europe the figure is 740. The MMR for sub-Saharan Africa is 542, compared with 10 in Europe.

In South Sudan, Chad, Sierra Leone, Nigeria, Central African Republic, Somalia, Mauritania, Guinea-Bissau, Liberia, Afghanistan – the 10 countries with the highest maternal mortality ratio (MMR) – the annual rates of reduction are stagnating or slowing.

The US has seen maternal deaths rise from 12 per 100,000 live births in 2000 to 19 in 2017.

Southern Asia has made the greatest strides in maternal survival with a nearly 60% reduction in the MMR since 2000. But India, along with Nigeria, accounted for a third of global maternal deaths in 2017.

A conference in November, organised by the UNFPA and the Kenyan and Danish governments, will be calling on governments to increase their efforts to end preventable maternal deaths.

On Thursday, the UN also published data that showed child deaths had been cut by almost half between 1990 and 2018. The total number of under-five deaths fell to 5.3 million in 2018 from 12.5 million in 1990.

“Around the world, birth is a joyous occasion. Yet, every 11 seconds, a birth is a family tragedy,” said Henrietta Fore, Unicef’s executive director. “A skilled pair of hands to help mothers and newborns around the time of birth, along with clean water, adequate nutrition, basic medicines and vaccines, can make the difference between life and death. We must do all it takes to invest in universal health coverage to save these precious lives.”