How many preterm births happened last year?
We count the number of babies born too early to plan services for families.
In 2022, 622 babies were born too early, before 37 weeks of pregnancy. Of these, 90 babies were born very early, before 32 weeks of pregnancy.
Over the past 10 years, the absolute number of preterm births decreased in San Francisco because the total number of births decreased. The percentage of preterm births did not change.
These line graphs show the total number of births in San Francisco that were born preterm and very preterm.
Data notes and sources
Data notes and sources
Data source:
- California Department of Public Health (CDPH) Vital Record Business Information System (VRBIS). VRBIS data include one birth certificate record for each and every baby born in California.
- Data were analyzed by the San Francisco (SF) Department of Public Health Maternal Child & Adolescent Health Epidemiology Section.
Data notes:
- Preterm birth is defined as live birth before 37 weeks of pregnancy. Very preterm birth is live birth before 32 weeks of pregnancy.
- We count preterm births experienced by San Francisco residents between January 1 and December 31 of each year.
- Babies born before 37 weeks of pregnancy, may not have fully developed brain, eyes, lungs, liver, or other organs.
- Babies born very early, before 32 weeks of pregnancy, may have serious health problems.
- In 2013, there were 8,673 total births. In 2022, there were 7,050 total births.
Data limitations:
- Data are not shown if the number of preterm births in the group is less than 20 to protect the privacy of individual people in the group. For small groups, please see the days of pregnancy lost because of preterm birth for the group.
- The total numbers shown here may undercount the true numbers, because we do not count preterm births that happened outside of California, in other states or countries.
- We do not count babies delivered in San Francisco by people who are not San Francisco residents. The California Department of Public Health VRBIS data include one birth certificate record for each and every baby born in California.
Who experienced preterm birth? What groups had more than 20 preterm births in the past 3 years?
Knowing the number of preterm births by population group helps to plan services.
Each baby born too early may need extra services, such as intensive care in the hospital. Community support can help each family.
In California, in the past 10 years, very preterm babies needed about 10 times more services. The average cost of hospital care for a very preterm baby was $223,931, compared to $2,433 for babies born at term.
This figure shows the number of preterm births and very preterm births over time. The selector allows you to choose a population group to find out how many babies or families in the selected population group may need support.
Data notes and sources
Data notes and sources
Data source:
- California Department of Public Health (CDPH) Vital Record Business Information System (VRBIS). VRBIS data include one birth certificate record for each and every baby born in California.
- Data were analyzed by the San Francisco (SF) Department of Public Health Maternal Child & Adolescent Health Epidemiology Section.
Data notes:
- Abbreviations: Black/AA: Black or African American, CPMC: California Pacific Medical Center; UCSF: University of California San Francisco; ZSFG: Zuckerberg San Francisco General.
- Race and ethnicity were self-reported by the parent(s) and grouped by the California Department of Public Health, which separates multi-race Hispanic and single race Hispanic groups.
- Quality of prenatal care was checked using the Kotelchuck index
- Within two weeks of every live birth, birth clerks at the hospital or midwives in the community record details about the birth. The birth record includes information about problems the birthing parent faced during pregnancy and the services they received.
Data limitations:
- Data are not shown if the number of preterm births in the group is less than 20 to protect the privacy of individual people in the group. For small groups, please see the days of pregnancy lost because of preterm birth for the group.
- The numbers shown here may undercount the true number of preterm births.
- We do not count babies delivered in San Francisco by people who are not San Francisco residents.
- We do not count preterm births delivered by San Francisco residents outside of California, in other states or countries.
- Housing information was only available for 2019-2021.
- The birth record notes if the birthing parent was ever diagnosed by a doctor with health conditions including high blood pressure, diabetes, or infection before or during pregnancy. The birth record data may be incomplete because of health conditions that were not diagnosed.
People having their first birth and people age 35 or older had over 800 preterm births.
Where did preterm births happen?
Information about where people lived when they were pregnant helps direct services to the places where people need services.
In the past 3 years, the San Francisco zip codes with the most preterm births were 94112, 94124 and 94110.
This figure shows the number of preterm births by zip code in the past 3 years.
Data notes and sources
Data notes and sources
Data source:
- California Department of Public Health (CDPH) Vital Record Business Information System (VRBIS). VRBIS data include one birth certificate record for each and every baby born in California.
- Data were analyzed by the San Francisco (SF) Department of Public Health Maternal Child & Adolescent Health Epidemiology Section.
Data notes:
- Abbreviations: Black/AA: Black or African American, CPMC: California Pacific Medical Center; UCSF: University of California San Francisco; ZSFG: Zuckerberg San Francisco General.
- Race and ethnicity were self-reported by the parent(s) and grouped by the California Department of Public Health, which separates multi-race Hispanic and single race Hispanic groups.
- Quality of prenatal care was checked using the Kotelchuck index
- Within two weeks of every live birth, birth clerks at the hospital or midwives in the community record details about the birth. The birth record includes information about problems the birthing parent faced during pregnancy and the services they received.
Data limitations:
- Data are not shown if the number of preterm births in the group is less than 20 to protect the privacy of individual people in the group. For small groups, please see the days of pregnancy lost because of preterm birth for the group.
- The numbers shown here may undercount the true number of preterm births.
- We do not count babies delivered in San Francisco by people who are not San Francisco residents.
- We do not count preterm births delivered by San Francisco residents outside of California, in other states or countries.
- Housing information was only available for 2019-2021.
- The birth record notes if the birthing parent was ever diagnosed by a doctor with health conditions including high blood pressure, diabetes, or infection before or during pregnancy. The birth record data may be incomplete because of health conditions that were not diagnosed.
More information
See linked pages about preterm birth in San Francisco