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PubMed This is a summary of 20 peer-reviewed journal articles Updated
Maternal-Fetal Medicine · Congenital Cytomegalovirus

Understanding Fetal CMV & Initial Diagnosis

At a Glance

A fetal CMV diagnosis means a pregnant person has contracted cytomegalovirus, but transmission to the baby is not guaranteed. If the virus does pass to the fetus, 85% to 90% of babies are born completely asymptomatic. Specialists monitor these pregnancies closely with advanced ultrasounds.

Receiving a diagnosis of cytomegalovirus (CMV) during pregnancy can feel overwhelming and frightening. It is often a virus many parents have never heard of until it affects their own family [1][2]. If you are feeling anxious, confused, or even guilty, please know that these emotions are a natural response to an unexpected medical challenge [2][3]. CMV is an extremely common virus, and most people contract it at some point in their lives, often without ever knowing it [4][5].

Many pregnant individuals wonder how they caught the virus. CMV is most commonly contracted through contact with the saliva or urine of young children, particularly toddlers [6][7]. Understanding this often helps alleviate the heavy maternal guilt that frequently accompanies a diagnosis.

What is CMV?

Cytomegalovirus (CMV) is a member of the herpesvirus family [4]. In healthy adults and children, it usually causes mild symptoms—like a common cold or fatigue—or no symptoms at all [4]. However, when a person is infected for the first time while pregnant, or if a previous infection reactivates, the virus can potentially pass through the placenta to the developing fetus. When this happens, it is called congenital CMV (cCMV) [4][8].

Understanding the Type of Infection

Doctors categorize maternal CMV infections into two main types, which help determine the risk of the virus passing to the baby:

  1. Primary Infection: This occurs when a person catches CMV for the very first time during their pregnancy [8]. This type carries a higher risk of passing the virus to the fetus, ranging from about 30% to 50% [9][8].
  2. Non-Primary (Recurrent) Infection: This happens when a person who was infected with CMV in the past has the virus “wake up” (reactivation) or is infected with a different strain of the virus (reinfection) [8]. The risk of passing a non-primary infection to the fetus is much lower, estimated at approximately 1% to 3.5% [10][11].

Stabilizing Facts for New Diagnoses

While the uncertainty of a CMV diagnosis is difficult, there are several key facts that can provide a clearer perspective on the situation:

  • Transmission is not guaranteed. Even with a primary infection—the type with the highest risk—more than half of all fetuses (approximately 50% to 70%) remain completely uninfected by the virus [9].
  • Most babies are born without symptoms. If the virus does pass to the baby, the vast majority (about 85% to 90%) are asymptomatic at birth, meaning they show no outward signs of the infection [12][8].
  • Medical monitoring is highly effective. Advanced tools like specialized serial ultrasounds and fetal MRIs allow your care team to closely monitor the baby’s development and look for specific markers of the virus [13][14].
  • Delivery plans usually don’t change. A cCMV diagnosis does not automatically require a C-section. Vaginal delivery is typically safe and appropriate unless there are other obstetric reasons [15].

Next Steps in Your Care

A diagnosis is the first step toward specialized care. Your medical team may recommend a consultation with a Maternal-Fetal Medicine (MFM) specialist—an expert in high-risk pregnancies—to discuss options for monitoring or potential treatments [16][17]. Confirming the timing of the infection is often done through serology testing, which looks at different antibodies (IgG and IgM) and their avidity (how strongly they bind to the virus) to estimate when the infection occurred [18][19]. This information helps your doctors tailor a plan that is specific to your pregnancy [20].

Common questions in this guide

What is the risk of passing CMV to my baby during pregnancy?
If you catch CMV for the first time during pregnancy, the risk of passing it to your baby is about 30% to 50%. If you have had CMV before and it reactivates or you are infected with a new strain, the risk is much lower, at roughly 1% to 3.5%.
Will my baby have symptoms if they get congenital CMV?
The vast majority of babies who contract the virus in the womb are asymptomatic at birth. About 85% to 90% of these infants will show no outward signs of the infection when they are born.
How did I catch CMV while pregnant?
CMV is a very common virus that is most frequently caught through contact with the saliva or urine of young children, particularly toddlers. Many adults experience only a mild cold or no symptoms at all when they are infected.
How do doctors monitor my baby after a CMV diagnosis?
Your care team will closely monitor your baby's development using specialized tools like serial ultrasounds and fetal MRIs. These detailed imaging tests allow doctors to check for specific markers of the virus throughout your pregnancy.
Does a fetal CMV diagnosis mean I need a C-section?
No, a diagnosis of congenital CMV does not automatically require a C-section. Vaginal delivery is typically safe and appropriate unless there are other, unrelated obstetric reasons that make surgery necessary.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Was my infection 'primary' or 'non-primary,' and what does that mean for my baby's risk?
  2. 2.Given the timing of my infection, what is the specific likelihood of the virus passing to the fetus?
  3. 3.What are the next steps for monitoring the pregnancy, such as specialized ultrasounds or fetal MRI?
  4. 4.If the virus has been transmitted, what are the chances that my baby will have no symptoms at birth?
  5. 5.How will we confirm the baby’s status immediately after birth (e.g., saliva or urine testing)?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

References (20)
  1. 1

    Neonatal screening for congenital cytomegalovirus infection in Tehran, Iran, using Guthrie cards.

    Noorbakhsh S, Farhadi M, Haghighi F, et al.

    Iranian journal of microbiology 2020; (12(3)):198-203.

    PMID: 32685115
  2. 2

    Awareness of Cytomegalovirus Infection among Pregnant Women in Geneva, Switzerland: A Cross-sectional Study.

    Willame A, Blanchard-Rohner G, Combescure C, et al.

    International journal of environmental research and public health 2015; (12(12)):15285-97 doi:10.3390/ijerph121214982.

    PMID: 26633451
  3. 3

    Perspectives of women on screening and prevention of CMV in pregnancy.

    Beaudoin ML, Renaud C, Boucher M, et al.

    European journal of obstetrics, gynecology, and reproductive biology 2021; (258()):409-413 doi:10.1016/j.ejogrb.2021.01.035.

    PMID: 33548895
  4. 4

    Cochlear implant performance in children deafened by congenital cytomegalovirus-A systematic review.

    Kraaijenga VJC, Van Houwelingen F, Van der Horst SF, et al.

    Clinical otolaryngology : official journal of ENT-UK ; official journal of Netherlands Society for Oto-Rhino-Laryngology & Cervico-Facial Surgery 2018; (43(5)):1283-1295 doi:10.1111/coa.13142.

    PMID: 29768731
  5. 5

    Burden of sequelae and healthcare resource utilization in the first year of life in infants born with congenital cytomegalovirus (cCMV) infection in Germany: A retrospective statutory health insurance claims database analysis.

    de Lepper M, Stephan AJ, Wölle R, et al.

    PloS one 2023; (18(11)):e0293869 doi:10.1371/journal.pone.0293869.

    PMID: 37972113
  6. 6

    Pregnant women's knowledge and behaviour to prevent cytomegalovirus infection: an observational study.

    Vena F, D'Ambrosio V, Pajno C, et al.

    Journal of perinatal medicine 2021; (49(3)):327-332 doi:10.1515/jpm-2020-0301.

    PMID: 33095754
  7. 7

    Development and Assessment of a Prenatal Cytomegalovirus (CMV) Educational Survey: Implementation and Impact in a Metropolitan University-Based Clinic.

    Schaefer MR, Holttum J, Olson M, et al.

    International journal of women's health 2020; (12()):1205-1214 doi:10.2147/IJWH.S276214.

    PMID: 33363413
  8. 8

    Maternal cytomegalovirus immune status and hearing loss outcomes in congenital cytomegalovirus-infected offspring.

    Demmler-Harrison GJ, Miller JA,

    PloS one 2020; (15(10)):e0240172 doi:10.1371/journal.pone.0240172.

    PMID: 33035237
  9. 9

    Diagnosis and antenatal management of congenital cytomegalovirus infection.

    , Hughes BL, Gyamfi-Bannerman C

    American journal of obstetrics and gynecology 2016; (214(6)):B5-B11.

    PMID: 26902990
  10. 10

    Human cytomegalovirus non-primary infection during pregnancy: antibody response, risk factors and newborn outcome.

    Zelini P, d'Angelo P, De Cicco M, et al.

    Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases 2022; (28(10)):1375-1381 doi:10.1016/j.cmi.2021.09.013.

    PMID: 34555536
  11. 11

    Cytomegalovirus infection in pregnancy.

    Davis NL, King CC, Kourtis AP

    Birth defects research 2017; (109(5)):336-346 doi:10.1002/bdra.23601.

    PMID: 28398680
  12. 12

    Secondary cytomegalovirus infections: How much do we still not know? Comparison of children with symptomatic congenital cytomegalovirus born to mothers with primary and secondary infection.

    Scaramuzzino F, Di Pastena M, Chiurchiu S, et al.

    Frontiers in pediatrics 2022; (10()):885926 doi:10.3389/fped.2022.885926.

    PMID: 35928677
  13. 13

    First-line noninvasive management of cytomegalovirus primary infection in pregnancy.

    Denef M, Noel L, Bruck G, et al.

    Journal of perinatal medicine 2022; (50(3)):270-276 doi:10.1515/jpm-2021-0384.

    PMID: 34923781
  14. 14

    Cytomegalovirus (CMV) seroprevalence among women at childbearing age, maternal and congenital CMV infection: policy implications of a descriptive, retrospective, community-based study.

    Ben Shoham A, Schlesinger Y, Miskin I, et al.

    Israel journal of health policy research 2023; (12(1)):16 doi:10.1186/s13584-023-00566-9.

    PMID: 37098565
  15. 15

    Amniocentesis to diagnose congenital cytomegalovirus infection following maternal primary infection.

    Dinsmoor MJ, Fette LM, Hughes BL, et al.

    American journal of obstetrics & gynecology MFM 2022; (4(4)):100641 doi:10.1016/j.ajogmf.2022.100641.

    PMID: 35526782
  16. 16

    Congenital Cytomegalovirus Targeted Screening Implementation and Outcomes: A Retrospective Chart Review.

    Ronner EA, Glovsky CK, Herrmann BS, et al.

    Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery 2022; (167(1)):178-182 doi:10.1177/01945998211044125.

    PMID: 34520270
  17. 17

    Short- and long-term neurological outcomes of congenital cytomegalovirus infection.

    Özdemir FMA, Taşçi Yildiz Y, Gümüşer Cinni R, et al.

    Turkish journal of medical sciences 2024; (54(3)):529-536 doi:10.55730/1300-0144.5819.

    PMID: 39050004
  18. 18

    Congenital cytomegalovirus infection in pregnancy: a review of prevalence, clinical features, diagnosis and prevention.

    Naing ZW, Scott GM, Shand A, et al.

    The Australian & New Zealand journal of obstetrics & gynaecology 2016; (56(1)):9-18 doi:10.1111/ajo.12408.

    PMID: 26391432
  19. 19

    Pathogenesis of developmental anomalies of the central nervous system induced by congenital cytomegalovirus infection.

    Kawasaki H, Kosugi I, Meguro S, Iwashita T

    Pathology international 2017; (67(2)):72-82 doi:10.1111/pin.12502.

    PMID: 28074532
  20. 20

    Congenital Cytomegalovirus Infection: From Silent Threat to Vaccine Horizon.

    Moutsopoulou RA, Markou A, Lianou A, et al.

    Vaccines 2025; (13(9)) doi:10.3390/vaccines13090929.

    PMID: 41012132

This page provides educational information about fetal CMV during pregnancy. Always consult your Maternal-Fetal Medicine specialist or obstetrician for advice tailored to your specific diagnosis and pregnancy.

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