Seems like every time we talk to someone about the fact that we are carrying twins, we discover a new and exciting fact about twins. It occurred to me that I must still be in shock, otherwise I would be out there reading and researching our current situation instead of walking around in an ignorant haze.

So I did some research.

Here is what I found.

1. Are we having identical or fraternal twins?

The likelihood of identical twins is uniformly distributed in all populations around the world. The exact cause for the splitting of an embryo is unknown. It is spontaneous and not effected by family history or fertility drugs. They occur in 1 out of 250 births on average worldwide. Our twins have two separate sacs and two separate placentas but this does not rule them out as identical. 

Most twins are fraternal.  Fraternal twins develop from two separate eggs. Fraternal twins are conceived when two eggs are released during ovulation. Because of fertility drugs, the birth rate for twins has gone up 65 percent since 1980. Before it was one in 89. These days, about one in 32 births are twin births.

2. Are there any factors that may have increased my chances of having twins?

If fraternal twins run in a female’s family, her odds of conceiving twins are much greater. It is passed down from mother to mother. Or if the mother carries the twin gene and has a son, he may pass it down to one of his daughters who will then be more likely to have twins. My mother is not a twin. Nor is my husband’s mother.

Decreasing our chances even more is my Asian ethnicity. China has the lowest rate of twins with the chance for multiple births averaging only one in 300.

Another factor that increase twins that doesn’t fit us – we did not previously have a multiple pregnancy. 

Also, we did not take any fertility drugs. Fertility drugs increase your chance of having multiples from one in 89 to one in 4.

With each pregnancy you are more likely to conceive twins. Perhaps having two other children previously is a factor for us.

More twins are conceived in July, and the least in January. We conceived July.

More multiple births occur if the mother is obese. I was not obese when I conceived. Maybe soon I will be, though.

Older mother’s have an increased chance of conceiving twins. I’m 38 years old. That’s old.

3. I also read that twin have a 50% chance of delivering before 37 weeks. Maybe I won’t have Taurus babies after all.

4. I am more likely to have a boy/girl combo. Between 30-39 you are more like to have opposite sex. Older women are more likely to produce more than one egg at a time. Between 20-29, same sex is more likely.