More than 2100 pregnant Colombian women are infected with the mosquito-borne Zika virus.
Colombia's national health institute announced the statistic on Saturday (local time), as the disease continues its spread across the Americas.
The virus has been linked to the devastating birth defect microcephaly, which prevents foetus' brains from developing properly. There is no vaccine.
There are 20,297 confirmed cases of the disease in Colombia, the national health institute said in an epidemiology bulletin, among them 2116 pregnant women.
There are so far no reported cases of microcephaly or deaths from the virus in Colombia.
Zika cases have been confirmed in 23 countries and territories in the Americas and scientists are racing to develop a vaccine for the virus.
The health ministry has said Zika infection falls within the health requirements women must meet to get abortions in the country, which restricts the procedure unless patients are victims of rape, have significant medical problems or the foetus is fatally deformed.
Many women, especially those living far from large cities, struggle to find abortion providers even when they meet the legal requirements and illegal abortions are widespread.
The government has urged women to delay pregnancy for six to eight months to avoid potential infection. Officials expect up to 700,000 cases.
Brazil is the country hit hardest by the disease. It has reported around 3700 cases of microcephaly strongly suspected to be related to Zika.