United Nations Population Division in the context of "Belt and Road Initiative"

Sub-replacement fertility is a total fertility rate (TFR) that (if sustained) leads to each new generation being less populous than the older, previous one in a given area. The United Nations Population Division defines sub-replacement fertility as any rate below approximately 2.1 children born per woman of childbearing age, but the threshold can be as high as 3.4 in some developing countries because of higher mortality rates. Taken globally, the total fertility rate at replacement was 2.33 children per woman in 2003. This can be "translated" as 2 children per woman to replace the parents, plus a "third of a child" to make up for the higher probability of males born and mortality prior to the end of a person's fertile life. In 2023, the global average fertility rate was around 2.2 children born per woman.

Replacement-level fertility in terms of the net reproduction rate (NRR) is exactly one, because the NRR takes both mortality rates and sex ratios at birth into account.

The maternal mortality ratio is a key performance indicator (KPI) for efforts to improve the health and safety of mothers before, during, and after childbirth per country worldwide. Often referred to as MMR, it is the annual number of female deaths per 100,000 live births from any cause related to or aggravated by pregnancy or its management (excluding accidental or incidental causes). It is not to be confused with the maternal mortality rate, which is the number of maternal deaths (direct and indirect) in a given period per 100,000 women of reproductive age during the same time period. The statistics are gathered by WHO, UNICEF, UNFPA, World Bank Group, and the United Nations Population Division. The yearly report started in 1990 and is called Trends in Maternal Mortality. As of the 2015 data published in 2016, the countries that have seen an increase in the maternal mortality ratio since 1990 are the Bahamas, Georgia, Guyana, Jamaica, Dem. People’s Rep. Korea, Serbia, South Africa, St. Lucia, Suriname, Tonga, United States, Venezuela, RB Zimbabwe. But according to Sustainable Development Goals report 2018, the overall maternal mortality ratio has declined by 37 percent since 2002. Nearly 303,000 women died due to complications during pregnancy.

With an exceptionally high mortality ratio compared to other U.S. states, the government of Texas created the Maternal Mortality and Morbidity Task Force in 2013.