My husband would love a 3rd child, from my understanding things that could increase your chances of having twins are:
Being a twin
Twins in the family
Having had previous pregnancies
Being over 30
Being of a BMI over 30
Nearing Perimenopause
Aided Fertility.
Given that I am a fraternal twin, twins run in both families, I have 2 children, Being 33, a BMI over 30 & have high FSH levels (even though I'm a lot younger than most I am nearing perimenopause) I wonder if twins would be a more likely outcome?