No, but you may notice baby noticing the further along you get. I am 26 weeks 3 days and had sex with my man 3 days ago, i swear to you i will never forget what i felt at the end, it made me laugh so hard. When all was said and done, i went to put my hand on my stomach, instinct for me, and i noticed baby was all balled up on my right side up by my hip lol. it was like she was saying OH GOD PLEASE MAKE IT STOP rofl. But on a more serious note, for most it is safe, i am high risk and its still safe for me, So really unless your doctor specifies that sex is a no go for you i would assume its perfectly safe :) just inquire about it at your next ultrasound, or call your OB that you have been dealing with, they will be able to tell you for sure :)
Nope. Not unless the Dr tells you otherwise