Health officials say tens of thousands of IUDs and other forms of birth control are badly needed in Puerto Rico to help prevent unintended pregnancies during an outbreak of Zika, the tropical disease linked to birth defects.

The Centers for Disease Control and Prevention released the estimate Friday. CDC officials said 138,000 young Puerto Rican women do not want to get pregnant but are not using effective .

Zika virus is mainly spread by mosquitoes. An epidemic in Latin America and the Caribbean is now hitting Puerto Rico. Zika causes no illness in most people. But there's mounting evidence linking infection in pregnant women to subsequent .

The CDC also released new guidance about how to protect against possible sexual spread of Zika.

More information: CDC report: www.cdc.gov/mmwr