Overbearing inlaws

Ok I just need to vent. My mil works at our local hospital (also so do I) but she works in surgery, with a lot of the OB drs. She keeps going to each one before my next apt asking them questions, nothing patient information related really, but annoying nonetheless. So this past weekend I told her I was 15 weeks and some days and our next apt was a blood draw only then the anatomy scan would be a few weeks later. She then proceeded to go to the dr she knew I was seeing and said “she’ll be 18 weeks can’t they go-ahead and find out the gender?” MEANWHILE, she’s discussing this with her husband and son, but leaves me out of the conversation. Obviously listening to anyone other than her sons is a problem bc I literally told her 3 days prior I was only 15 weeks 🙄. So then she got our hopes all up just to talk to another dr who said “this apt is a blood draw and then 2 weeks later they’ll get an ultrasound and go over the results and find out the gender” EXACTLY WHAT I TOLD HER. My sister in law had a baby in May and said that she did the same thing and ran to the drs after every appt when they told her about it. I seriously love my inlaws, they’re so sweet and would do anything for us, but damn, boundaries!? I need some advice on how to stop all this without being a complete ass. Anything would be appreciated!!