Mothers in the UK are three times more likely to die around the time of pregnancy compared with those in Norway.
Researchers found that Slovakia had the highest maternal death rate among the countries studied. The UK had the second highest.
The rates of death among mothers in pregnancy and up to 42 days after the birth of their children varied from 2.7 per 100,000 live births in Norway to 10.9 in Slovakia. In the UK, there were 9.6 maternal deaths for every 100,000 babies born.