Twins in the Family

Just a random snapshot to make this post more aesthetically pleasing.

The question I've gotten the most often when people find out we are having twins is

"Do twins run in your family?"

The short answer is yes. But I don't know how much it upped our chances of having twins based on the current theories on what causes twins to happen more often.

Ever since 7th grade science I've been interested in genetics. I did a little research on the genetics behind twins.

Here are a few sites I used for research if you are interested and so you know I didn't just make this stuff up. Most facts I tried to verify from more than one source so I'm pretty sure they are accurate but I don't guarantee it.:
WebMD
Increased chances of having twins (only #8 and possibly #1 apply to me, #4 is interesting)
Myths about Multiples (skipping a generation, father's gene contribution)
Good ol' Wikipedia (good overview)

On Matt side:
His maternal Grandmother had a fraternal set of boys AND an identical set of girl twins. That's crazy I know! That's on top of 3 more children in a very short time frame. These grandparents definitely have some good twin advice. His grandma says if she could have died from lack of sleep she would have died. Very reassuring. She also says sometimes you figure out how to do something that seems impossible because there is no other choice. It has to be done.

So this must have really upped our chances for twins, right? Wrong. According to "the experts" the father's family history has nothing to do with whether there are two eggs dropped or if the egg splits. So even though we are the first of the kids or grand kids to have twins after Grandma her genes probably weren't a factor for us.

My side:
My maternal aunt had fraternal twins, a boy and a girl. This could have upped my chances as it is inherited from the mother's side and fraternal twins are genetic.

My cousin Alison had identical twins boys in 2008. Identical twins aren't genetic, just chance.

My other cousin Stefani (Alison's sister) had identical twin girls in 2009. See reason above. Pretty cool that they both had twins right after each other. Makes you wonder if the scientists have it wrong and identical twins can also be genetic.

My cousin Nathan and his wife Melissa have fraternal twins, a boy and girl. But again I'm related to Nathan who is on my dad's side and I don't share any genes with Melissa.

According to the ultra sound tech, who does a lot of multiple ultrasounds she is pretty sure our twins are fraternal. Although this website says it can be difficult to tell without DNA testing. They are both in separate amniotic sacks, which is better as far as less competition for nutrients and less possible complications during birth with tangled cords etc., and they think there are two placentas. The membrane between the 2 babies is also pretty thick, another good sign that they are fraternal. She even looked at my ovaries in the ultrasound and she is pretty sure she can see where my left ovary dropped 2 eggs. So unless an egg split really early they are probably fraternal. I am good with that. I worry about mixing up twins and they will have enough in common as it is.

Here's the scary part about fraternal twins. Unlike identical twins, which aren't inherited and aren't more likely to happen again, if you have fraternal twins your chances of having twins again is quadrupled. Yikes!

***Disclaimer- if I missed any twins or got the identical/fraternal wrong let me know. I'd also be interested to hear how many of my twin relatives have had DNA testing to verify if they are identical or fraternal (# of placentas, 2 sacks can be inconclusive). DNA testing usually isn't necessary with boy/girl twins (only 3 cases of identical boy/girl twins recorded see unusual twinnings). Yeah I didn't know that was possible either.

Make a guess in the poll to the right>>>>>>>>>>>>>>>>>>>>>>

They will hopefully both cooperate for my next ultrasound (between 16-19 weeks) to see if they are boys or girls. If you want to tell me what you voted in the comments (especially close family members) that would be great. I made a chart of guesses for Charlotte's baby book and I'm sure the twins will find it interesting as well.