Monkeypox (mpox) is a rare disease caused by the monkeypox virus, a member of the Orthopoxvirus family. Data on the impact of mpox on pregnant individuals are limited, and it is unclear if pregnant people are more susceptible to the virus or if the infection is more severe during pregnancy. However, mpox virus can be transmitted to the fetus during pregnancy or to the newborn by close contact during and after birth. Adverse pregnancy outcomes, including spontaneous pregnancy loss and stillbirth, have been reported in cases of confirmed mpox infection during pregnancy. Preterm delivery and neonatal mpox infection have also been reported.
While smallpox, caused by a similar orthopoxvirus (variola virus), was eradicated in 1980, it was associated with more severe illness during pregnancy and risk for adverse pregnancy outcomes than mpox. The signs and symptoms of mpox virus infection in people who are pregnant appear similar to those in non-pregnant individuals with mpox virus infection, including prodromal symptoms (e.g., fever, headache, lymphadenopathy, malaise, sore throat, and cough) and rash.
During pregnancy, the cause of fever may be difficult to differentiate from other infections, such as intra-amniotic infection (chorioamnionitis), until the rash appears. A rash in a pregnant individual with risk factors for mpox virus infection needs to be differentiated from dermatoses of pregnancy, including polymorphic eruption of pregnancy, and mpox lesions can mimic those in other infections. Thus, patients with rashes initially considered characteristic of more common infections (e.g., varicella-zoster or sexually transmitted infections) should be carefully evaluated for a characteristic mpox rash, and diagnostic testing should be considered, especially if the person has epidemiologic risk factors for mpox virus infection. Co-infections of mpox virus and sexually transmitted infections (STIs) and HIV have been reported, and the presence of an STI does not rule out mpox, so a broad approach to testing is encouraged.
Pregnant individuals with mpox virus infection are more likely to experience severe disease and adverse pregnancy outcomes than non-pregnant individuals. Therefore, medical treatment should be prioritized if needed. While most non-pregnant adults with mpox virus infection experience mild illness and recover spontaneously, pregnant, recently pregnant, and breastfeeding individuals should be prioritized for medical treatment if needed because of the probable increased risk of severe disease during pregnancy, the risk of transmission to the fetus during pregnancy or to the newborn by close contact during and after birth, and the risk of severe infection in newborns.
Close monitoring for severe disease and pregnancy complications is important. The decision to treat and monitor a pregnant individual as an outpatient or in the inpatient setting should be individualized. Tecovirimat (also known as TPOXX or ST-246) should be considered the first-line antiviral for pregnant, recently pregnant, and breastfeeding individuals. Tecovirimat is an antiviral medication that is FDA-approved for the treatment of human smallpox disease caused by variola virus in adults and children. Its use for other orthopoxvirus infections, including mpox, is not approved by the FDA. Therefore, CDC holds a non-research expanded access Investigational New Drug (EA-IND) protocol that allows for the use of tecovirimat for primary or early empiric treatment of non-variola orthopoxvirus infections, including mpox, in adults and children of all ages.
Information about the impact of tecovirimat on reproductive development is limited to animal studies.
Preventing infection is the best approach for pregnant people, especially during outbreaks or in areas with known transmission. To prevent mpox virus infection, pregnant people should follow the same prevention measures as non-pregnant people, which include avoiding close contact with infected animals and people, washing hands frequently with soap and water, and avoiding touching the face, especially the mouth and nose.
If a pregnant person is identified as a close contact of someone with mpox virus infection, they should be evaluated for exposure and monitored closely for symptoms. Vaccination against smallpox, a similar orthopoxvirus, can offer some protection against mpox virus, but routine vaccination against smallpox is no longer recommended in the United States because the disease has been eradicated.
In addition, pregnant people who are at high risk of exposure to mpox virus, such as healthcare workers or laboratory personnel who handle specimens, should be aware of their risk and take appropriate precautions. They should wear personal protective equipment (PPE), such as gloves, gowns, and masks, when handling potentially infectious materials or when caring for patients with suspected or confirmed mpox virus infection.
In conclusion, mpox virus infection during pregnancy is a rare but serious concern, as it can lead to adverse pregnancy outcomes and transmission of the virus to the fetus or newborn. Pregnant people who have been exposed to mpox virus should be closely monitored for symptoms and evaluated promptly if they develop a fever or rash. Treatment with tecovirimat should be considered if indicated, but the risks and benefits should be discussed with the patient using shared decision-making.
Preventing infection is the best approach for pregnant people, and they should follow the same prevention measures as non-pregnant people, including avoiding close contact with infected animals and people, washing hands frequently, and wearing PPE when necessary. Pregnant people who are at high risk of exposure to mpox virus should take extra precautions to protect themselves and their unborn or newborn child.
While data on mpox virus infection in pregnancy are limited, healthcare providers should stay up to date on the latest guidance and recommendations from public health authorities and work closely with their patients to provide appropriate care and management.