Golf fans attending the third round of the US Open at Shinnecock Hills Saturday were left stunned when an airplane buzzed the course towing an advertisement promoting obtaining abortion pills by mail.

The ad was paid for by Mayday Health, a Massachusetts-based nonprofit dedicated to highlighting the availability of abortion medication and birth control pills across the country.

“It just felt gross and divisive. I’m sure that’s exactly what this group intended, which is a real shame,” one fan told The Post about the stunt.

“These kids kept pointing at the banner asking their parents ‘What does that say?’ And it was clear they had no clue how to respond. I mean, what do you even say?

“Especially when there are so many golfers and spectators who are strong in their faith — this felt like an intentional distraction by outside agitators to undermine the tournament,” the fan added.

The banner flew over the Southampton property for about 90 minutes, witnesses said.

The choice of venue was likely no accident, as the US Open famously concludes on Father’s Day weekend each year.

Mayday Health was founded in 2022 after the Supreme Court’s Dobbs v. Jackson Women’s Health Organization decision, which struck down its 1973 Roe v. Wade ruling and allowed each state to set its own abortion policy.

Mayday’s advertising ploys have caused controversy across America. In 2022, Mississippi clashed with the group over its billboards touting ways women can terminate their pregnancies.

In March, the group reached a settlement with South Dakota in which it agreed to “remove any signs with deceptive and unlawful advertisements,” according to the state attorney general’s office.

The United States Golf Association and Mayday Health did not immediately respond to requests for comment.

Wyndham Clark secured his second US Open win on Sunday, shooting a four-under-par 276 to hold off Sam Burns by one shot.