Downs?!

Ive been worried about everything since this is my first pregnancy & I’m 39. Im going to be 40 in April. Well, last night my boyfriend mentioned his dad told him to make sure he gets Down syndrome test because of my age. Like wtf why would he even mention it?! Are the odds that high I just need some reassurance I guess. My boyfriend is going to be 30 this year and has 2 healthy children already.. if that’s relevant at all.