Friendship and pregnancy

MiRo
Hi girls ! I would love your opinion ! I had 4 good friends which they all a have small kids.until now they were all hanging out together with their kids and husbands and leave my be and me on the outside just because we had no kids. They were just invite us on their kids birthdays. Now, I'm 7montjs pregnant and I thought they would like to hang out with us but they don't ! And every time we see them on a dinner together they are all like oh hi we just sit ! 
It pains so much see them all together  and in jealous too but I believe they don't like our company anymore! How should I behave from now on especially when our baby arrives? Should I talk to them first again and ask hanging out together ?