The Department of Health and Human Services (HHS) launched a review and audit in September into federal funding of research involving fetal tissue.
As for future aborted-tissue research that applies for federal funding but takes place outside NIH, "an ethics advisory board will be convened to review the research proposal and recommend whether, in light of the ethical considerations, NIH should fund the research project-pursuant to a law passed by Congress".
Now, the government will also not renew a $2m (£1.5m) contract with the University of California San Francisco (UCSF) for research using tissue from elective abortions. There have always been strict rules around how it can be procured and used.
Ending the use of fetal tissue by the National Institutes of Health has been a priority for anti-abortion activists, a core element of President Donald Trump's political base.
Scientists were incensed."I think it's ultimately a bad, nonsensical policy", said Larry Goldstein, distinguished professor in the University of California San Diego's department of cellular and molecular medicine, who has advised scientific groups that use fetal tissue. "Taxpayer funding is better spent promoting alternatives that are already being used in the production of treatments, vaccines, and medicines and to expand approaches that do not depend on the destruction of unborn children often through late-term abortion", Dannenfelser added. Yet the Trump administration is ending the medical research by government scientists using human fetal tissue.
Wednesday's announcement turns on its head an assurance late previous year at an invitation-only workshop at NIH on the debate over federal support for fetal tissue research by Brett Giroir, HHS' assistant secretary for health. This new ruling will also not prevent privately funded research from using tissue samples harvested from abortions.
Megan Thielking contributed reporting. NIH said that $98 million figure represents the entire budget for the grants at issue, even if only a smaller portion of a particular grant was devoted to fetal tissue research. As a result, NIH froze procurement of new tissue.
In December, the National Institutes of Health informed a principal investigator at one of those labs - at UCSF - that it was withholding the next $2 million annual installment of a multiyear contract that is the lab's only source of funding.
Critics argue that modern science has alternatives to replace fetal tissue in the laboratory, such as using tissue from infants who undergo heart surgery or stem cells that grow into organ-like clumps in lab dishes. The contract previously had been renewed annually and later in 90-day increments.
At a House hearing on the issue last December, neuroscientist Sally Temple told lawmakers the consensus opinion in the scientific community is that there is now no adequate substitute for fetal tissue in some research areas.
At least one university's government funding will be terminated, effective immediately, although officials suggested that other research may allowed to continue under intense scrutiny.
At the invitation-only workshop at NIH late a year ago, Giroir, who oversaw much of the audit, told participants that any alternative source of tissue "must be as predictive, as reliable and as validated as existing models", according to a scientist who was present.