The Democratic-controlled House yesterday approved a $96.4 billion appropriations bill for major social welfare programs after adding $300 million for education and job training and renewing its opposition to federal financing of abortions for poor women.

Approval of new anti-abortion language, even stronger than that in existing bans on abortion funding, prompted a testy exchange between two leading antagonists on the issue.

In an otherwise bland discourse against abortion, William E. Dannemeyer (R-Calif.) suggested that, as the nation's fertility rate drops, abortions threaten the nation's ability to produce more taxpayers to help pay off the national debt.

"I'm shocked to hear that American women are [regarded as] breeder reactors," Rep. Barbara A. Mikulski (D-Md.) retorted angrily. "I think American women do more than breed to pay off deficits."

The new abortion language, approved 231 to 184, would ban Medicaid funding of abortions. Existing language allows government payment for abortions to protect a woman's life.

However, proponents of the strengthened abortion ban said they expect that existing language, allowing financing of abortions in cases where a woman's life is "endangered," will be retained by a House-Senate conference.

The extra money for schools and jobs, with a promise of even more in a stopgap funding bill that must be passed next week, was accepted by senior Democrats on the Appropriations Committee under pressure from the Democratic leadership and many rank-and-file liberals.

Protests had been growing among Democrats that the bill, as drafted by Rep. William H. Natcher (D-Ky.) and Rep. Silvio O. Conte (R-Mass.), failed to fulfill spending promises in the fiscal 1984 budget resolution adopted by Congress earlier in the year.

Natcher, chairman of the subcommittee with jurisdiction over the programs, succeeded in lopping $100 million from a $400 million add-on proposal by Majority Leader James C. Wright Jr. (D-Tex.).

But Natcher agreed to additional spending in the stopgap "continuing resolution," estimated at $450 million or more, for education and other programs that the House sought to expand in new authorization legislation it passed earlier this month.

Conte, who had warned earlier that any fattening of the bill would prompt a veto, said after the 302-to-111 vote to add the $300 million that he thought President Reagan would sign it if the Republican-controlled Senate "restrained itself." The Senate Appropriations Committee version of the legislation is about the same size as the House bill.

The House bill, approved, 310 to 101, exceeds Reagan's request for discretionary social welfare spending by $3.8 billion, including the $300 million add-on.

But it is $4.4 billion shy of spending all of the money allowed by the congressional budget resolution for the same areas, which include major health, education, nutrition and jobs-related programs.

The fact that the bill was closer to Reagan's budget than to Congress' spending blueprint rankled many Democrats hoping to reverse Reagan's pattern of cutting social welfare programs over the last two years.

While some harsh words were expressed privately outside the chamber, yesterday's debate was a model of gentility, at least partly in deference to Natcher and Conte.

Members also were constrained from more ambitious add-on efforts by the fact that, under rules for consideration of the bill, a point of order could be made against any spending that exceeds current authorization levels. There could be more latitude on the continuing resolution.

With the House and Senate apparently in near-agreement on spending levels that may meet Reagan's approval, the huge labor, health, education and human services bill could be enacted by Oct. 1 or shortly thereafter.

This would be the first time in at least five years that the bill, the largest domestic appropriations measure, has not been funded by stopgap financing, at least for a major part of the year.