The Trump administration announced Thursday that human fetal tissue derived from abortions can no longer be used in research funded by the National Institutes of Health.

The policy, long urged by anti-abortion groups, expands restrictions issued during President Donald Trump’s first term.

The government has funded research involving fetal tissue for decades, under both Republican and Democrat administrations. The tissue, which otherwise would be thrown away, has been critical for certain research, including ways to fight HIV and cancer. Opponents of fetal tissue use say there are now alternatives, although many scientists say there aren’t always adequate substitutes.

In a statement Thursday, NIH Director Jay Bhattacharya acknowledged the agency “has long maintained policies governing the responsible and limited use of human fetal tissue in biomedical research.”

Its use has declined since 2019. The $47 billion agency counted just 77 projects funded in 2024 that included fetal tissue.

The first Trump administration ended the use of fetal tissue on NIH's campus and set up additional hurdles for non-government scientists seeking NIH funding, restrictions that were subsequently lifted by the Biden administration. Thursday's new policy covers all NIH-funded research.

NIH documents say the policy doesn’t end the use of “cell lines” created years ago from fetal cells. Those are cloned copies of cells, such as embryonic stem cells, adapted to grow continuously in labs. Bhattacharya’s statement said NIH will soon seek comment about potential ways “to reduce or potentially replace reliance on human embryonic stem cells.”