CHICAGO — Democratic veep candidate Tim Walz has repeatedly heavily suggested his wife used in vitro fertilization to get pregnant.

Turns out she didn’t.

Minnesota first lady Gwen Walz was forced to clarify late Monday that she used a different fertilization procedure — intrauterine insemination — to conceive their two children.

Both IVF and IUI are assisted reproductive technologies, but IUI is when sperm is injected into the woman’s uterus around the time of ovulation, while IVF entails the fertilization of an egg and sperm in a lab dish.

Democrats have pummeled Republicans over their concerns about IVF, lumping the issue in with GOP efforts to restrict access to abortion.

Walz, speaking about IVF to a boisterous crowd in Philadelphia when presidential nominee Kamala Harris unveiled him as her VP pick, had said, “This gets personal for me and my family.”

On a few occasions, the Minnesota governor went further and point-blank claimed that she used IVF.

“Today is IVF day. Thank God for IVF, my wife and I have two beautiful children,” Walz said on MSNBC in July.

In a clip once shared by the Harris campaign, he added, “If it was up to [GOP wannabe veep JD Vance], I wouldn’t have a family because of IVF and the things that we need to do reproductive [sic]. My kids were born, you know, that way.”

The campaign has said Walz’s wife used “reproductive health care like IVF” to become pregnant with their children.

But Walz’s comments led to a widespread belief that his wife used IVF — leading her to finally try to set the record straight.

“Like so many who have experienced these challenges, we kept it largely to ourselves at the time – not even sharing the details with our wonderful and close family,” Gwen Walz told The Post in a statement. “The only person who knew in detail what we were going through was our next-door neighbor.

“She was a nurse and helped me with the shots I needed as part of the IUI process. I’d rush home from school, and she would give me the shots to ensure we stayed on track.”

Vance, who is poised to debate Walz on Oct. 1 on CBS-TV, slammed Walz over the revelation.

“Today it came out that Tim Walz had lied about having a family via IVF. Who lies about something like that?” he chided.

Harris-Walz campaign rep Mia Ehrenberg fired back at Vance.

“The Trump campaign’s attacks on Mrs. Walz are just another example of how cruel and out of touch Donald Trump and JD Vance are when it comes to women’s healthcare,” she said in a statement to The Post. 

While both IVF and IUI are assisted reproductive technologies, they are generally viewed very differently in the anti-abortion movement.

IVF typically involves numerous attempts, resulting in excess embryos.

That aspect — embryo attrition — is generally the sticking point for many anti-abortion activists. They generally feel that the extra embryos should not be discarded.

In February, the issue of IVF was thrust into the national spotlight after the Alabama Supreme Court concluded embryos in IVF procedures can be considered unborn children.

That ruling prompted some IVF clinics to halt operations over fears that they could be liable for embryos lost to accidents.

Parents who lost embryos in lab accidents had filed the lawsuit that triggered the court’s ruling.

Alabama has since passed a law granting criminal and civil immunity to IVF clinics.

In June, Senate Republicans tanked a Democrat-led effort to pass a bill guaranteeing national access to IVF. They argued the legislation went too far, including with its language requiring private health insurance to cover assisted reproduction treatments without religious carveouts.

Senate Republicans have pitched an alternative IVF bill, as most top Republicans in Congress, with a few exceptions, and former President Donald Trump back access to IVF treatments.

Walz has also previously come under fire over other claims he made about his 24 years in the Army National Guard.

Walz had claimed that he deployed to serve in combat. Despite deploying to places such as Italy, he never saw combat. At times, he also talked about “weapons of war that I carried in war.”

A press release from his first congressional campaign described Walz as a “Command Sergeant Major.” However, while he was technically promoted to that position, he left before finishing off the training needed to obtain that title and was therefore still a rank below.

Walz’s 2006 congressional campaign also falsely denied that he was drinking ahead of his 1995 driving arrest. Court records show that he admitted to drinking while driving 96 mph in Nebraska, where the speed limit was 55 mph.