Brazil Zika Birth Defects

Pregnant women who have travelled to regions with active Zika infections should be given ultrasounds to check for evidence of microcephaly, a birth defect in infants associated with small heads that has been associated with Zika infection. (Felipe Dana/Associated Press)

The U.S. Centers for Disease Control and Prevention on Tuesday issued guidelines for doctors caring for pregnant women during the Zika outbreak, a mosquito-borne illness linked with microcephaly marked by unusually small head size and brain damage.

The new guidelines urge doctors to ask their pregnant patients about their travel history to areas with Zika virus transmission.

Women who had traveled to regions in which Zika virus is active and who report symptoms during or within two weeks of travel should be offered a test for Zika virus infection. 

Pregnant women who had no clinical symptoms associated with the  infection should be offered an ultrasound to check the fetus' head size or check for calcium, two signs of microcephaly. 

Last week, Canadian and U.S. health officials urged pregnant women to consider postponing travel to countries dealing with an outbreak of Zika virus following reports of birth defects in children born to women in Brazil infected with the virus.

The World Health Organization provides an updated list of countries in Latin America and the Caribbean where infection with Zika is a risk. 

With files from CBC News