Questions & Answers
Smallpox - Vaccine Safety
Back to Parent Q&A Category Back to All Smallpox Q&A Back to All Q&A Back to Smallpox

Reproductive Health

Questions
Answers
  1. Should pregnant women receive the smallpox vaccine?

    No. Pregnant women should not receive the smallpox vaccine, unless they have been exposed to smallpox. Most of the time, when pregnant women get smallpox vaccine, the pregnancy goes well. In an outbreak, personal benefit from vaccination may outweigh the risks of vaccination. Women who are pregnant or planning to become pregnant within 4 weeks after vaccination should NOT get the smallpox vaccine. In addition, anyone who has a close contact who is pregnant should not get the vaccine. Close contacts include anyone living in your household and anyone you have close, physical contact with such as a sex partner or someone you share a bed with.

    Smallpox vaccine can cause a very rare but serious complication in the fetus called fetal vaccinia. Less than 50 cases of fetal vaccinia have ever occurred. Most babies born to women who got smallpox vaccine will be fine. If a woman is vaccinated, she should avoid pregnancy for a month. She should wait until the vaccination site has completely healed and the scab has fallen off before trying to become pregnant after vaccination. Until that time, effective measures should be taken to prevent pregnancy, such as abstinence, birth control pills, injections, implants, or IUDs. Other methods of birth control, such as condoms, diaphragms, spermicide, and natural family planning are less effective than abstinence.

    Women uncertain about whether or not they are pregnant should get a medical evaluation. Clinics should display warning signs about asking women if they are pregnant. Urine or blood tests can help women find out if they are pregnant before immunization.



  2. Should women or men defer conceiving a child after receiving the smallpox vaccine?

    Women receiving a smallpox vaccination should wait until the scab has fallen off and the vaccination site has completely healed before trying to become pregnant after vaccination. Generally, this means vaccinated women should wait four weeks after their smallpox vaccination. Until that time, effective measures should be taken to prevent pregnancy, such as abstinence, birth control pills, injections, implants, or IUDs. Other methods of birth control, such as condoms, diaphragms, spermicide, and natural family planning are less effective than abstinence.

    Vaccinated men may wish to wait a similar amount of time before fathering a child. Until the vaccination site has completely healed, they can be the source of spreading vaccinia to a close contact (such as a sex partner). Covering the vaccination site is very important for both men and women.



  3. Does the vaccine cause sterility?
    No formal studies have ever been performed on sterility rates after smallpox vaccination. Smallpox vaccine has been given to billions of people around the globe over many decades and no effects on sterility have ever been found.

  4. Is smallpox vaccine safe for women who are breastfeeding?

    Women who are breastfeeding should not get the smallpox vaccine. Breastfeeding places the baby close to the vaccination site on a woman's arm. This advice is true even if women are pumping and then bottle-feeding breast milk. It is unknown whether the vaccine virus or antibodies pass on to the baby through breast milk. A woman who desires to maintain her milk supply may continue to pump breast milk, but the milk should be discarded until the vaccination site has completely healed and not be given to the baby.



  5. Is it safe for a woman to breastfeed her baby if a close contact received the smallpox vaccine?

    Yes, if clothing is not contaminated and proper hand washing is used. Anyone who receives the smallpox vaccine should remember to wash their hands with soap and warm water after direct contact with the vaccination site, or anything that has touched the vaccination site (bandages, clothing, towels, bedding, etc.). This is will help prevent the spread of vaccinia virus to contacts, including young babies.



  6. If a breastfeeding mother who has close contact with a recently vaccinated person develops a rash, should she stop nursing?

    First, she should check with her healthcare provider to determine if the rash is related to the smallpox vaccine. If she has a vaccine-related rash, breastfeeding should not take place until all scabs from the rash have fallen off and the skin is completely healed. A woman who desires to maintain her milk supply may continue to pump breast milk, but the milk should be discarded until her scabs fully separate and the skin is completely healed.



  7. Is smallpox vaccination or close contact with a recently vaccinated person during pregnancy a reason to consider pregnancy termination?

    There have been less than 50 cases of fetal vaccinia ever reported in the world. Because fetal vaccinia is so rare, smallpox vaccination during pregnancy should not be a reason to consider termination of pregnancy.



  8. Are pregnant women who receive the smallpox vaccine more likely than other pregnant women to have a miscarriage?

    Smallpox vaccine has not been associated with an increased risk of miscarriage. There is no evidence that smallpox vaccine causes spontaneous abortion (miscarriage).



  9. Are there any other special risks after birth for children who are born to mothers who received smallpox vaccine during pregnancy?

    Except for the rare case of fetal vaccinia, smallpox vaccination of pregnant women has not been linked with premature birth, low birth weight, or other serious birth problems.



  10. Are there special considerations at the time of delivery for women exposed to smallpox vaccine during pregnancy?

    Most women who receive smallpox vaccine during pregnancy will deliver normal babies, and standard delivery procedures should be followed. All pregnant women who have received the smallpox vaccine during pregnancy should let their healthcare provider and their baby's healthcare provider know about their vaccination. Their providers should contact the registry by calling 619.553.9255 or e-mailing NHRC-birthregistry@med.navy.mil.



  11. What is being done to learn more about the effects of smallpox vaccine on pregnant women and their babies?

    DoD works with the CDC in operating the National Smallpox Vaccine in Pregnancy Registry. This registry is used to monitor the outcomes of pregnant women who received the smallpox vaccine. This will help us better understand the risks of smallpox vaccine in pregnancy. The registry has already provided important information, which is generally reassuring to women in these circumstances.

    Pregnant women who received the smallpox vaccine, or pregnant women whose close contacts received the smallpox vaccine, may contact their healthcare provider or their state health department for help in enrolling in the registry. Health-care providers and staff from state health departments (see http://emergency.cdc.gov/agent/smallpox/faq/pregnancy.asp) are encouraged to report all exposed pregnant women to the registry by calling 619.553.9255 or e-mailing NHRC-birthregistry@med.navy.mil. To learn more, click here: www.smallpox.mil/pregnancy