Taylor Swift Is Upset That Lady Gaga Addressed Pregnancy Rumors

Taylor Swift is shaking her head over the fact Lady Gaga spoke out on pregnancy rumors -- saying she shouldn't have had to do it ... let alone deal with people's speculation.

The singer commented on Gaga's video from yesterday -- where she straight up denied she's got a bun in the oven ... something a lot of people thought was the case after some photos of her at her sister's wedding over the weekend went viral.

The pics made it look like LG's belly was somewhat protruding, and amid a lot of questions -- Gaga finally shot it down ... and did so by invoking one of TayTay's own lyrics, no less.

In her caption from Tuesday, Gaga wrote ... "not pregnant - just down bad cryin at the gym."

That's from one of Taylor's songs -- which may be why Taylor commented Wednesday, writing ... "Can we all agree that its invasive & irresponsible to comment on a woman's body. Gaga doesn't owe anyone an explanation & neither does any woman."

Of course, what's interesting here is the fact that Taylor herself has (unfortunately) also been subjected to pregnancy rumors of late -- with some suggesting she was expecting based on her appearance at recent "Eras" tour concerts.

On its face, it appears Taylor is making a statement about this whole phenomenon as it pertains to her too -- clearly, she knows what it's like to have folks gawking/gossiping.

Gaga and Taylor are friendly ... so it's not really surprising T-Swift is weighing in. Still though ... Taylor doesn't comment on a ton of stuff on social media usually, so this is significant.