WASHINGTON — Rep. Michelle Steel, a two-term Republican congresswoman from a competitive Orange County-area district, announced Thursday she’s withdrawing her co-sponsorship of the Life at Conception Act, saying she favors in vitro fertilization.

“I do not support federal restrictions on IVF,” Steel said on the House floor. “I’m removing myself from the bill because it could create confusion about my support for the blessings of having children through IVF. I hereby remove my name as cosponsor.”

The reversal comes two days after Steel won her primary to advance to the general election this fall, securing enough support from Republicans to move forward. Also on Tuesday, NBC News reported that Steel was voicing support for IVF even as she co-sponsored the bill, which could threaten the use of IVF for pregnancy, a process in which unused embryos can be discarded. At the time, her office didn’t respond to queries about how she reconciles those stances.

NBC News has not projected who her opponent will be, but veteran Derek Tran, a Democrat and consumer rights attorney, is currently leading other rivals for the second of the top two positions. He responded Thursday to Steel’s shift in position by calling her a liar.

“Michelle Steel just admitted she’s been lying to every one of her constituents about her abortion-banning, IVF-restricting legislation,” Tran said in a written statement. “She can try to explain this away all she wants, but Californians see her exactly for who she is — a reproductive right-dismantling extremist who has no business representing the interests of California’s 45th District. That’s why we’re going to defeat her this November.”

Steel’s about-face represents a broader dilemma for Republicans over IVF in the wake of an Alabama ruling against reproductive rights that threatened the procedure and elevated it into the national consciousness.

The congresswoman has rolled out a nonbinding resolution expressing support for the use of IVF to achieve pregnancy but has not signed on to legislation that would assure legal protections for it.