Question

If twins run in our families, how likely is it that my husband and I will have twins?

Answer

Twin pregnancies have many more complications than singleton pregnancies, so don't pray too hard! If you do conceive twins, you automatically move into a "high risk" category, so while twins are cute and fun, I'd rather see you conceive one baby and have an uncomplicated pregnancy. In the U.S. the overall rate of dizygotic twins (fraternal) is 12 for every 1,000 births. The rate for monozygotic twins (identical) is about 4 for every 1,000 births. Dizygotic twins are usually due to multiple ovulation, which might run in families, and the likelihood of having them depends in part on the age of the mother (women over 35 have twice as many dizygotic twins as younger women).

The best predictive evidence we have is this: If the woman is a dizygotic twin or has dizygotic twin siblings, that might mean her mother released several eggs when she ovulated; therefore she might do the same and conceive twins. Twins are not known to occur more frequently when it is the husband who is the twin, because twinning depends on the woman's egg, or eggs!