Rep. Keven Stratton, R-Orem, the bill's sponsor, said two rounds of drugs are used in a medically induced abortion, and research shows that 15 percent to 50 percent of fetuses are still viable after just the first pill and might be carried to full term if a woman changes her mind.
His bill requires that women be given such information before the procedure.
But House Minority Leader Brian King, D-Salt Lake City, said the mandated information "is something that is simply not well established in science," adding that it is based on an experiment with "a handful of patients, literally. ... It's simply not sound science."
Stratton and allies disagreed. Rep. Ray Ward, R-Bountiful, a physician, said medical groups believe the information "is medically accurate. Not only is it accurate, it is reasonable and important information for a woman to have as she finds herself in this type of a situation."
The Utah Medical Association opposes the legislation, said spokesman Mark Fotheringham.
The American Congress of Obstetricians and Gynecologists has issued a fact sheet that confirms that pregnancy will continue in 30 percent to 50 percent of cases where a woman takes only the first medication.
It has recommended that "in the rare situation where a woman takes mifepristone and then changes her mind, doing nothing and waiting to see what happens is just as effective as any" course of intervention in continuing the pregnancy, and without the potential side effects.
Medically induced abortions comprise just 16.5 percent of U.S. abortions, according to a 2014 bulletin of the physicians' group.
King complained that legislators every year find additional ways to "interject ourselves between a woman and a doctor about the decision that she makes and has made to proceed with an abortion, which is perfectly legal."
Last year, Utah lawmakers required physicians to provide anesthesia to any woman seeking an abortion after 20 weeks to "eliminate or alleviate organic pain to the unborn child" a highly disputed claim. Some of the handful of doctors who perform abortions in the state recently told The Associated Press that they are not complying with the law because they can get no guidance from the state on how to do so safely.
King said Republicans often fight federal micromanagement or "nanny state-ism," but he said, "Why is it so difficult to live that way on this issue of abortion?"
Agreeing was Rep. Susan Duckworth, D-Magna, who added, "I am opposing the fact that men continually make these presentations and these arguments about what should be done to a woman's body." Men outnumber women in the House by a 61-14 margin.
But Rep. Karianne Lisonbee, R-Clearfield, rose as a woman to defend what she said is simply "an informed-consent bill. It requires physicians to provide scientifically factual information to their patients."
King also started a minor brouhaha when he said he is tired of some lawmakers who contend that abortion is "killing babies."
He said, "What we are talking about are zygotes and fetuses and embryos. …. When I hear an individual refer to an unborn child as a baby, I know immediately they are not to be taken seriously."
Some lawmakers called points of order, saying King was violating House decorum, but Rep. Eric Hutchings, R-Kearns, who was acting as chairman at the time, ruled he had not attacked any individual by name and therefore had not violated rules.
It led others to stand to defend their beliefs against abortion.
Rep. LaVar Christensen, R-Draper, said, "There most definitely is life in the womb, and that the Constitution protects life and liberty."
He added, "I personally believe in being faithful to 'in God we trust' and the creator."
He added, "I also disagree with the proposition that our vocabulary and our terminology is somehow wrong and that we are to accept the alternative premise that there is no life until there is a breath taken outside the womb."
Stratton said, "This is not a pro-life or a pro-choice bill. It is an informed-consent" bill, but added, "I will openly say that I am very concerned about the over 900,000 termination pregnancies we have in our country at this time."
He said his bill also would help to "honor womanhood, and the dignity and the grace and honor that it adds to the human experience. ... I am so grateful for my mother and all of our mothers whose choice to carry us and give us birth is a remarkable blessing to all of us today."