I never thought about anything like this with DD1 but I was worried up till 12 weeks with DD2 as I had no signs or sympotms that I was pregnant. Just after I fell pregnant with these two tho, my best friends SIL went into labour at 40wks and her precious little boy was still born. She'd only been checked by her OB 3 days before and everything was perfect. Since then I have been a bit paranoid every day and if I don't feel one of the twins move for more than a day I go get checked by one of my doctors. I feel a bit stupid when they get the portable ultrasound and everything is fine but my doctors are really good and say that we're better off checking and setting my mind at ease than having me stressing out over it.
Hoping everything goes well with everyones pregnancies!