It doesn't matter if twins run in your boyfriends family, that wouldn't affect you. If it runs on your mum's side (women like maternal nan, sister...) then you are more likely to follow suit as it has more to do with you ovulating more than one egg in a cycle for non identical twins and also the risk increases with age and number of pregnancies. Identical twins don't run in families as such as that is due to the fertilised embryo dividing down the middle to create two babies. Hope that makes sense!
I'm scared that will happen to me I go Friday for another ultra sound but I haven't had one since 7 weeks & we couldn't see much but twins run in the family of my boyfriend
I know of someone where they went for their 20 week ultrasound and found out there that they were having twins....I guess it is common.