The country's Roman Catholic Church has crusaded against the measure, which would make Uruguay only the second country in South America, along with English-speaking Guyana, to allow abortion without restriction in the first 12 weeks of pregnancy.
The nation's bishops issued a statement on Saturday saying that any lawmakers voting for the measure would be automatically excommunicated.
Socialist President Vasquez, himself a physician, said last year that he doesn't agree with legalized abortion - "neither philosophically nor biologically" - and would veto any bill to remove penalties.
Abortion is now banned altogether in Uruguay, a nation of 3.3 million people, though researches estimate that about 33,000 are performed each year at a cost of up to $800. Three Uruguayan doctors were sentenced to prison earlier this year for performing abortions.
Most countries in Latin America allow abortion only in cases of rape, when the mother's life is in danger or if the fetus has severe deformities. Only Cuba and Guyana allow abortions without restrictions in the first trimester.
Nicaragua banned abortion in all cases in 2006 and efforts to overturn full bans on abortion have repeatedly failed in other countries.
Mexico City last year approved abortion without limitation in the first trimester, but that is banned elsewhere in the country.