The Democratic vice presidential candidate, Minnesota Gov. Tim Walz, has been exposed for his tendency over the years to embellish his background and personal stories with half-truths and outright lies, most notably about his prior criminal history and military service record.

Walz has now been called out by Sen. JD Vance (R-OH), the Republican vice presidential nominee, for having been deceptive and dishonest with the public about the kind of fertility treatment he and his wife Gwen received to have children, according to CBS News.

The governor has strongly implied, if not directly claimed, that his two children were conceived through in vitro fertilization, or IVF, a method at the center of intense political debate this year, but his wife Gwen recently revealed that they actually received the far less controversial fertility treatment known as intrauterine insemination, or IUI.

Walz repeatedly implies IVF responsible for his children

The political controversy over IVF treatments erupted earlier this year when the Alabama Supreme Court, in a case involving the state's Wrongful Death of a Minor Act, ruled in February that the frozen embryos created during the IVF process counted as human beings for the purpose of wrongful death lawsuits.

Shortly after that, as the political debate over IVF intensified, Gov. Walz and his wife went public about their own experience with fertility treatments nearly two decades, with the governor often and repeatedly making it seem as though IVF was the sole reason he and his wife were able to have two children after struggling for years to get pregnant.

In a social media post after the Alabama ruling, per CBS News, Walz wrote, "Gwen and I have two beautiful children because of reproductive health care like IVF. This issue is deeply personal to our family and so many others. Don't let these guys get away with this by telling you they support IVF when their handpicked judges oppose it."

In July, after Vice President Kamala Harris' upstart campaign attacked Sen. Vance for, like nearly all other Republican senators, voting against a Democratic virtue-signaling bill that would have enshrined IVF treatments with federal protection, Walz jumped into the fray and again strongly implied that his beloved children were the direct results of the IVF procedures.

In an X post that shared the Harris campaign's critique of Vance, Walz wrote, "Even if you’ve never gone through the hell of infertility, someone you know has. When Gwen and I were having trouble getting pregnant, the anxiety and frustration blotted out the sun. JD Vance opposing the miracle of IVF is a direct attack on my family and so many others."

Gwen Walz received IUI treatments, not IVF

However, in a recent Glamour magazine profile piece about the Walz family's "fertility struggles" more than two decades ago, Gwen revealed that she did not ultimately get pregnant with their two children -- a daughter named Hope, 23, and a son named Gus, 17 -- through the IVF process but rather by way of the IUI procedure.

According to NBC News, there is a substantial difference between those two fertility treatments, as IVF involves fertilizing eggs in a laboratory to create frozen embryos that are then implanted in the mother's uterus while IUI simply involves injecting sperm directly into the uterus to fertilize an egg naturally.

The controversy over IVF stems from the fact that multiple frozen embryos are typically created in a lab and are then later discarded as trash once one has been successfully implanted. There is no similar controversy over the IUI process because a successful procedure results in a natural pregnancy with no leftover frozen embryos to throw away in the garbage.

Vance calls out Walz's IVF lies

On Tuesday, Sen. Vance responded to a video posted by Gov. Walz earlier in the month in which he dubiously claimed, "If it was up to JD Vance, I wouldn't have a family because of IVF."

Referencing the Glamour magazine article, Vance wrote, "Today it came out that Tim Walz had lied about having a family via IVF. Who lies about something like that?"

According to NBC News, the Ohio senator also told reporters of Walz's apparent compulsive -- or perhaps partisan -- dishonesty, "It’s just such a bizarre thing to lie about, right? There’s nothing wrong with having a baby through IVF or not having a baby through IVF. Like, why lie about it? I just don’t understand that."