Pregnancy and CMV: What Expectant Mothers Need to Know

Pregnancy brings many questions about infections and how they may affect a developing baby. Cytomegalovirus, commonly known as CMV, is one of the most common viral infections that can occur during pregnancy, yet it remains widely underrecognized among expectant parents. Understanding what CMV is, how it may be transmitted, and what options exist for testing and monitoring can help patients have more informed conversations with their obstetric care team. If you have questions about CMV or your pregnancy, call us for details.

What Is CMV and How Can It Affect Pregnancy?

CMV is a member of the herpesvirus family. According to the Centers for Disease Control and Prevention, CMV is so common that the majority of adults have been infected at some point in their lives, often without ever knowing it. In healthy adults, CMV typically causes mild or no symptoms. However, in the context of pregnancy, the picture becomes more complex.

In an episode of the Healthful Woman podcast, Dr. Shari Gelber joined Dr. Nathan Fox to discuss CMV and its potential impact on newborns. Dr. Gelber explained that there is an important clinical distinction between a primary CMV infection, meaning a first-time infection in a person who has not previously been exposed, and a reactivation, which occurs when a dormant virus becomes active again in someone who was previously infected.

Primary infections during pregnancy carry a higher risk of transmission to the baby and may be associated with more significant outcomes. Reactivation infections can also be transmitted, but the associated risks to the newborn are generally considered lower, though they are not without concern. As Dr. Gelber noted in the podcast, congenital CMV, meaning CMV present in a newborn from birth, is the leading non-genetic cause of hearing loss in children. Some infants with congenital CMV may also experience developmental delays or other neurological effects. Individual outcomes vary widely, and not all infants who are born with CMV will develop symptoms.

For patients receiving high risk obstetrics care, understanding the potential implications of CMV is an important part of comprehensive prenatal management.

Testing, Screening, and the Challenges of CMV Diagnosis During Pregnancy

One of the central themes of the Healthful Woman podcast episode on CMV is the complexity surrounding testing and screening. Unlike some other infections routinely screened for during pregnancy, CMV is not part of standard universal prenatal screening in the United States. This means many cases go unidentified until after delivery, or not at all.

Dr. Gelber outlined several reasons why screening is complicated. Serologic testing, which looks for antibodies in the blood, can help identify whether a patient has had a prior infection versus a new one, but interpreting these results requires clinical expertise. The presence of CMV-specific antibodies indicates past exposure, while the absence of antibodies suggests a patient is at risk for a primary infection. However, the timing and type of antibody detected matters significantly, and results must be interpreted carefully in the context of each individual pregnancy.

Fetal ultrasound may reveal certain findings that raise concern for congenital CMV, and specialized ultrasound services can play a meaningful role in monitoring pregnancies where CMV exposure is suspected. In some situations, amniocentesis may be offered to test the amniotic fluid directly for the presence of CMV. Decisions about testing are individualized and depend on clinical history, gestational age, and patient preferences.

Patients in high-risk situations benefit from subspecialty involvement, which is precisely the kind of collaborative care model that maternal-fetal medicine practices are designed to provide.

Treatment, Prevention, and Advances in Care for CMV in Pregnancy

The podcast discussion with Dr. Gelber also covered the current landscape of treatment and prevention. As of now, there is no universally approved antiviral treatment for CMV infection during pregnancy, though research is ongoing. Antiviral medications such as valganciclovir have been studied in the context of congenital CMV in newborns and may be prescribed to affected infants after birth under specific clinical conditions. In the podcast, Dr. Gelber discussed how advances in neonatal and pediatric care have contributed to improved outcomes for babies born with congenital CMV, particularly in the area of hearing preservation.

Vaccine development for CMV has been an area of active research for decades. While no CMV vaccine is currently approved for clinical use, scientific progress continues and this remains a priority in the field. Prevention during pregnancy currently focuses on hygiene measures, particularly for patients who work closely with young children, who are a common source of CMV transmission.

For patients with a known or suspected CMV exposure during pregnancy, evaluation through a practice offering high risk pregnancy care allows for individualized risk assessment and coordinated follow-up. Outcomes for babies with congenital CMV have continued to improve as medical understanding of the virus deepens and multidisciplinary care becomes more accessible.

Why Choose Our Practice for High Risk Pregnancy Care?

Our maternal-fetal medicine practice was built on a model that blends the depth of academic medicine with the accessibility and patient focus of private practice. Providers at our practice have been recognized among “Best Doctors,” “New York Best Doctors,” Castle Connolly Top Doctors, and Super Doctors.

We are a member of the U.S. Women’s Health Alliance and are proud to be a Rainbow Practice, welcoming patients from all backgrounds. For pregnancies involving complex concerns such as CMV exposure, our team offers the subspecialty expertise, advanced ultrasound capabilities, and coordinated care that informed patients are looking for. We invite you to reach out and speak with a member of our team.

What is congenital CMV?

Congenital CMV refers to a cytomegalovirus infection that is present in a newborn at birth, having been transmitted from the birthing parent during pregnancy. It is the most common congenital viral infection in the United States and the leading non-genetic cause of hearing loss in children. Not all infants born with CMV will develop symptoms, but outcomes vary and early identification is important. Consult your provider if you have concerns.

Should I be tested for CMV during pregnancy?

CMV is not part of routine universal prenatal screening in the United States. Testing may be recommended based on specific risk factors, symptoms, or ultrasound findings. If you have concerns about CMV exposure during your pregnancy, speak with your obstetric provider or a maternal-fetal medicine specialist. Individual clinical history is a key factor in determining whether testing is appropriate for your situation.

What is the difference between primary CMV infection and reactivation during pregnancy?

A primary CMV infection occurs when someone is exposed to CMV for the first time. Reactivation occurs when a previously dormant CMV infection becomes active again. Primary infections during pregnancy are generally associated with a higher risk of transmission to the baby and potentially more significant outcomes. Reactivation can also result in transmission but is considered lower risk in most cases. Your provider can help assess which situation may apply.

What ultrasound findings might suggest CMV exposure in a pregnancy?

Certain ultrasound findings may raise concern for congenital CMV, including abnormalities of the fetal brain or other organs. Specialized ultrasound services performed by experienced maternal-fetal medicine providers can help evaluate these findings in greater detail. Ultrasound is one component of a broader diagnostic workup and is used alongside clinical history, serologic testing, and in some cases amniocentesis to guide care decisions.

Is there a treatment for CMV during pregnancy?

There is currently no universally approved antiviral treatment for CMV infection during pregnancy. Research is ongoing, and antiviral medications may be considered for affected newborns under specific clinical circumstances after delivery. If your pregnancy has been affected by CMV, a maternal-fetal medicine specialist can discuss current evidence, monitoring options, and coordination with neonatal care providers to support the best possible outcome for your baby.

If your pregnancy involves concerns about CMV or other complex conditions, our maternal-fetal medicine team is here to help. We provide expert, individualized care for patients navigating high risk pregnancy situations. Call us for details to schedule a consultation with one of our experienced providers.

Maternal Fetal Medicine blogs are intended for educational purposes only and do not replace certified professional care. Medical conditions vary and change frequently. Please ask your doctor any questions you may have regarding your condition to receive a proper diagnosis or risk analysis. Thank you!