The maternal mortality rate reached 10.83 per 100,000 live births in 2016, up 24.6 percent from 2015, according to a report on health conditions in Beijing released by the municipal health and family planning commission.
China allowed all married couples to have two children in 2016. This followed an earlier policy easing in 2013, allowing couples to have a second child if either parent was an only child.
The latest change ended the one-child policy, which was implemented in the late 1970s to rein in a surging population.
Figures show 18.67 million new births were reported in China in 2016, up 11 percent on 2015. Among the new births, 45 percent were second children.
Gao Xiaojun, spokesman of the Beijing health commission, said more births had put pressure on limited obstetrical resources in the city, which was one of the reasons for the higher maternal mortality rate.
A large number of pregnant women, many elderly and more likely to suffer complications, neglected regular antenatal inspections, which also contributed to the high maternal mortality, he said.
Gao said the city would further train medical practitioners and strengthen publicity to encourage pregnant women to receive regular antenatal checks.