Blood test

Hi all, just wanna check during first trimester appt at KKH, will they take husband’s blood test as well? My 2nd appt is on 30 Mar and was told that there was going to be Down Syndrome test and some blood tests, can’t remember if they mentioned need husband for blood test as well. If yes, what do they need it for? And what if husbands are not able to be around for quite some time like working overseas for few months, etc? Update: husband had to take a blood test