The bill would prevent people from deducting the cost of an abortion from their taxable income, except when the procedure is performed in cases of rape, incest or when a physician certifies that a woman's life would be in danger if she continues the pregnancy.

Current law, known as the Hyde Amendment, bars federal money for abortions, with the same exceptions as those in the bill. But the bill would make the Hyde Amendment federal law, rather than a provision added to other bills that must be voted every year.

Abortion opponents have charged that the health care overhaul contains a loophole for insurance policies. Obama's health care overhaul, passed last year, creates state marketplaces for insurance known as "exchanges." It allows participating plans to cover abortions, provided they collect a separate premium from policyholders and that money is kept apart from federal subsidies.

The bill disallows the tax credit for the expenses of a small employer health insurance plan that includes coverage for an abortion. Democrats said that amounts to a tax increase.

"I thought my Republican friends hated taxes, but apparently they hate reproductive freedom and women's rights even more," said Rep. Lynn Woolsey, D-Calif.

Supporters of the bill passed Wednesday say the health overhaul doesn't go far enough to make sure that no tax money is used to subsidize abortions. Congressional estimates say the bill would raise only a negligible amount of tax revenue.

Opponents say the bill would make it difficult if not impossible for many women to obtain medical insurance that covers abortions — even if they pay for it themselves. They say the legislation could put the Internal Revenue Service in the position of determining whether women who get abortions were sexually assaulted, so the agency can decide whether the procedure is tax deductible.

Rep. Louise Slaughter, D-N.Y., said the bill is really an effort to prevent insurance companies from covering abortions.

By law, people can deduct medical expenses that exceed 7.5 percent of their adjusted gross income, a threshold that increases to 10 percent in 2013. They can set aside tax-free money in health savings accounts and spend it on approved medical expenses. The IRS lists the cost of an abortion as an approved medical expense.

Although the House-passed bill is unlikely to go anywhere in the Senate, anti-abortion senators are pursuing similar legislation.

Sen. Orrin Hatch, R-Utah, who is up for re-election next year, is leading a group of senators who this week are introducing a bill to write the Hyde Amendment into permanent law.