What is SET-NET?

A mother holding her baby

CDC’s Surveillance for Emerging Threats to Mothers and Babies Network (SET-NET)

  • Detects the effects of health threats on pregnant people and their babies by collecting data from pregnancy through childhood.
  • Uses actionable information to help save and improve the lives of mothers and babies.


This surveillance approach builds upon the US Zika Pregnancy and Infant Registry. The Registry collected health information on pregnant people and their infants with laboratory evidence of Zika infection during pregnancy. Expanding this effort, state, local, and territorial health departments work with CDC to identify the impact of emerging health threats on pregnant people and their infants. This approach serves as a preparedness network that can be further expanded if new threats emerge.

A key part of this unique surveillance is the ability to find exposures during pregnancy and link them with health outcomes of pregnant people and infants. This innovative approach enables CDC and state, local, and territorial health departments to monitor exposures of concern during pregnancy and collect follow-up data on affected infants over time.

SET-NET collects information on the following infectious disease threats during pregnancy:

  • COVID-19
  • hepatitis C
  • syphilis
  • Zika
  • SET-NET will begin surveillance of congenital cytomegalovirus (CMV) in 2023.

CDC also places contractual field staff at health departments impacted the most by an exposure to support local and state surveillance efforts. Field staff also conduct educational outreach for healthcare providers and community members and help connect families to resources.

Goals and Impact

SET-NET data provided valuable information during the COVID-19 pandemic, demonstrating the risk of infection during pregnancy. This information was necessary for the development of public health guidance to prioritize pregnant people to receive COVID-19 vaccines which also helps to protect the infant. Read more about the value of SET-NET during the COVID-19 pandemic and its utility for future emergencies.

This system aims to determine how health threats, such as COVID-19, cytomegalovirus, hepatitis C, syphilis, and Zika, affect pregnant people and their infants. It also aims to track birth defects, developmental problems, and other disabilities as these children age, for up to 3 years. CDC scientists and health departments use these data to

  • Monitor and improve the health of pregnant people and infants;
  • Link families to medical and social services to get recommended care;
  • Strengthen laboratory and clinical testing to find emerging health threats quickly; and
  • Ensure public health is ready and prepared to meet the needs of pregnant people and infants during emergencies.

See the latest data on the impact of COVID-19 during pregnancy from a subset of participating jurisdictions.