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What is the omicron BA.2 variant and
how does it affect my pregnancy?

By Dr. Kristina Adams Waldorf, Sara Rutz, Isabelle Crary and Carly Baxter



What is the omicron BA.2 variant? 
Omicron BA.2 is a variant of the first omicron COVID-19 strain (called BA.1) that was first identified in the United States in December 2021. By mid-January 2022, more than  99% of COVID-19 cases in the U.S. were caused by the omicron BA.1. As the virus continues to spread from person to person, it mutates and stronger versions of the virus can take hold. In fact, there are even combinations of variants, including delta/omicron and omicron BA.1/BA.2 strains. The omicron BA.2 variant was first identified in the U.S. in January 2022. By the end of March 2022, about a third of the COVID-19 cases in the U.S. have been caused by the COVID BA.2 variant. We expect that number to continue to increase. Compared to the first omicron variant (called omicron BA.1), the omicron BA.2 variant appears to transmit more easily between people. The omicron BA.1/BA.2 combination variant is even 10% more transmissible than omicron BA.2 alone. 

What can I do to protect myself and my baby from omicron BA.2? 
Getting the COVID-19 vaccine and booster shot is the best way to protect yourself from the omicron BA.2 variant. The COVID-19 vaccine is safe during pregnancy and can help protect your and your baby from serious health complications and even death. However, pregnant individuals who are vaccinated are still nearly 2x more likely to have a breakthrough infection (a COVID-19 infection when vaccinated) than non-pregnant individuals. Given the risk even when vaccinated, and that the omicron BA.2 variant appears to be more infectious, wearing a well-fitted and protective mask such as an N95 will also help protect you from the omicron BA.2 variant. 

My state no longer required masks indoors. Why should I continue to wear them?
Pregnant individuals are more susceptible to infection, including COVID-19, and wearing a mask can help protect you from infection. Currently, there are no large studies of the effects of the omicron BA.2 variant on the mother’s or child’s health, although a wealth of evidence from thousands of pregnancies and prior variants indicates that COVID-19 infection can be very harmful to you and your baby. 

I’ve already had COVID-19. Can I still get infected? 
Unfortunately, there have already been cases of individuals getting infected with both the original omicron variant and the new omicron BA.2 variant. However, infection and recovery from the first omicron variant does appear to provide some protection against the omicron BA.2 variant. 



Meet the Authors

Kristina Adams Waldorf, MD

Kristina Adams Waldorf, MD is a Professor of Obstetrics and Gynecology and Adjunct Professor of Global Health at the University of Washington School of Medicine. She is an internationally recognized expert in how infections impact pregnancy and how vaccines and therapeutics protect the mother and fetus. She is Chair of the National Institutes of Health Obstetrics and Maternal-Fetal Biology Study Section. She is a member of the Center for Reproductive Sciences and the Center for Innate Immunity and Immune Diseases. Her grant support has come from the National Institutes of Health, the March of Dimes, Burroughs-Wellcome Fund, the Canadian Institute for Health Research and the Australian National Medical Research Council.

Sara Rutz

Sara Rutz graduated from the University of Alaska, Anchorage with a Bachelor of Science degree in Natural Sciences and a minor in Psychology. She is now a fourth year medical student at the University of Washington School of Medicine. Prior to medical school, she worked with diverse & underserved populations in patient care settings and as an insurance specialist for 5 years. She has been involved in research on improving outcomes for infants with Neonatal Opioid Withdrawal Syndrome, quality improvement in obstetric care, and providing up to date information as a volunteer for the COVID-19 Literature Surveillance Team. She is passionate about reproductive medicine and improving access to care for rural and underserved populations.

Carly Baxter

Carly Baxter graduated from the University of Puget Sound with a Bachelor of Science degree in Biology and a minor in French studies. She is now a third year medical student at the University of Washington School of Medicine. She has worked with the MaMHA (Maternal Mental Health Access) group coordinated by the University of Washington and WA Department of Health in an effort to reduce maternal mortality rates in WA state. She is passionate about reproductive justice, equitable health care access and volunteering within her community at local health fairs.

Isabelle Crary

Isabelle Crary graduated from Stanford University with a Bachelors of Arts in Human Biology. She is now a third year medical student at the University of Washington. She has been involved in research on anemia in pregnancy, breast cancer prevention and treatment, and adolescent nutrition. She is passionate about healthcare for individuals who are pregnant, reproductive justice and nutrition education.