Zika Virus Infection and Pregnancy



A specific type of mosquito can pick up Zika when it bites a person with the infection. The mosquito can then pass the virus to the next person it bites. Most Zika infections pass this way.

Zika can also pass from person to person. It may pass:

  • During sex when one partner has an active Zika infection
  • To an unborn baby if the mother had Zika during or just before pregnancy

Risk Factors

The risk is greater in those who have spent time in a high risk place without mosquito protection. Zika happens in:

  • South America, mostly Brazil; Colombia, Bolivia, Ecuador, French Guiana, Guyana, Paraguay, Suriname, and Venezuela
  • Mexico and Central America, mostly Guatemala, El Salvador; Honduras, and Panama
  • The Caribbean, mostly Barbados, Dominican Republic, Guadeloupe, Haiti, Martinique, Puerto Rico, and Saint Martin
  • Southeast Asia and the Pacific Islands
  • Africa



Symptoms do not always happen. If they do, they may show up a few days after the bite. These problems may last a few days to a week:

  • Fever
  • Rash
  • Eye redness and irritation
  • Headache
  • Joint and muscle pain

Zika infection in pregnant women may cause these problems for the baby:

  • Microcephaly—a small head due to poor growth of the brain
  • Brain defects
  • Eye problems
  • Hearing loss
  • Slow growth
  • Muscle stiffness and spasms
  • Seizures
  • Joints that are not normal


The doctor will ask about any recent exposure to Zika from travel or sex.

Blood and urine tests may be done to confirm Zika. Tests will look for the virus or signs that the body has fought the virus. It may be given to pregnant women who:

  • Are at risk and have symptoms of Zika
  • Have not had symptoms of Zika but who are at risk
  • May have been exposed and have had abnormal ultrasounds during pregnancy

A woman with a positive test may be referred to a maternal fetal medicine or an infectious diseases specialist. Those with an abnormal ultrasound will be referred to a maternal fetal specialist.



Medicine cannot treat Zika. Symptoms should pass on their own in a week. Rest and fluids can help.

Acetaminophen may be given to ease fever or pain. Nonsteroidal anti-inflammatory drugs (NSAIDs) and aspirin can cause problems in women who may also have dengue infection. NSAIDs should not be used until dengue infection is ruled out.

If a mosquito bites a person who is infected, it can pass the infection to someone else. Steps will be needed to avoid mosquito bites for about a week.


People who are pregnant or trying to become pregnant should not travel to places where Zika is spreading.

Those who are pregnant and live in areas with ongoing Zika transmission should:

  • Take steps to avoid mosquitoes
  • Not have sex, OR
  • Correctly use condoms with each act of vaginal, anal, or oral sex

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.