Results Summary

What was the research about?

In the United States, 10 to 15 percent of pregnant women have depression. Two ways of treating depression are taking medicine or going to talk therapy.

In this study, the research team looked at whether pregnant women with depression had a higher risk of having babies born at least three weeks too early, with a low birth weight, or were smaller than expected, compared with pregnant women without depression. The team also looked at the risk of these health problems for babies when pregnant women

  • Had therapy for depression
  • Took medicine for depression
  • Took medicine and also had therapy for depression

What were the results?

Pregnant women with untreated depression had a higher risk of having babies too early than those without depression.

Compared with pregnant women whose depression wasn’t treated, the risk of having a baby born too early was

  • The same in pregnant women in therapy for depression
  • Higher in pregnant women who took medicine for depression
  • Higher in pregnant women who took medicine for depression and also had therapy

Having depression didn’t affect the risk of babies having a low birth weight or being smaller than expected at birth. Neither did any of the treatments for depression.

Who was in the study?

The study looked at health records for 91,084 women who gave birth at one California health system. Of these, 37 percent were white, 25 percent were Asian, 6 percent were African American, and 5 percent were another race or the race was unknown; 26 percent were Hispanic. Also, 13 percent of women were ages 18–24, 63 percent were ages 25–34, and 24 percent were over age 35.

The research team found that 21 percent of the women had depression or reported signs of depression. Of these women

  • 7 percent were taking medicine
  • 39 percent were in therapy
  • 15 percent were taking medicine and were in therapy
  • 39 percent weren’t getting treatment

What did the research team do?

The research team looked at health record data on depression treatment, timing of birth, and birth weight and size. The team looked for a link between women’s depression and treatment and risk of health problems in their babies.

Providers, patient groups, and pregnant women with depression gave input during the study.

What were the limits of the study?

This study included only one California health system. Results may differ in other health systems. The research team didn’t assign treatment to the women by chance. For this reason, the team can’t be sure that the risk of babies’ health problems was due to women having depression, getting treatment, or something else. Also, this study didn’t look at the different medicines or types of therapy that women may have been using.

Future research could look at whether specific kinds of depression or types of therapy have clear effects on babies’ health. Researchers could also look at pregnant women who live in other places.

How can people use the results?

Women and their doctors can use the results when considering options for treating depression during pregnancy.

Final Research Report

View this project's final research report.

Peer-Review Summary

Peer review of PCORI-funded research helps make sure the report presents complete, balanced, and useful information about the research. It also assesses how the project addressed PCORI’s Methodology Standards. During peer review, experts read a draft report of the research and provide comments about the report. These experts may include a scientist focused on the research topic, a specialist in research methods, a patient or caregiver, and a healthcare professional. These reviewers cannot have conflicts of interest with the study.

The peer reviewers point out where the draft report may need revision. For example, they may suggest ways to improve descriptions of the conduct of the study or to clarify the connection between results and conclusions. Sometimes, awardees revise their draft reports twice or more to address all of the reviewers’ comments. 

Peer reviewers commented, and the researchers made changes or provided responses. The comments and responses included the following:

  • The reviewers expressed concern about the interpretation of the study findings given the statistical limitations that exist when testing multiple outcomes. The researchers acknowledged that the number of comparisons could increase the chance of a false-positive result and added this as a limitation of the study.
  • Reviewers suggested stratifying patients by their Patient Health Questionnaire-9 scores, a measure of depression severity. The researchers stated that the scores could not be used as a marker of depression severity in this case, since they collected the measures after treatment started. The researchers explained that the initiation of treatment could have affected depression severity. The researchers added a limitation regarding the lack of a pretreatment measure of depression severity, which could confound the interpretation of study results.

Conflict of Interest Disclosures

Project Information

De-Kun Li, MD, PhD
Kaiser Foundation Research Institute
Comparing Effectiveness of Treating Depression With and Without Comorbidity to Improve Fetal Health

Key Dates

September 2013
April 2019

Study Registration Information


Has Results
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Populations Populations PCORI is interested in research that seeks to better understand how different clinical and health system options work for different people. These populations are frequently studied in our portfolio or identified as being of interest by our stakeholders. View Glossary
Intervention Strategy Intervention Strategies PCORI funds comparative clinical effectiveness research (CER) studies that compare two or more options or approaches to health care, or that compare different ways of delivering or receiving care. View Glossary
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Last updated: January 25, 2023