unfortunately there is no way to increase your chances, it's all in the luck of the draw. twins happen when a zygote splits into two, or when there are two fertilizations, which is a random occurrence.
BUT-
1) twins are more likely in a family with a history of twins, triplets, etc.
2) women who have a higher BMI or are taller are more likely to have twins
3) older women are more likely to have multiples
4) women who have a daily intake of dairy products are more likely to have multiples
5) use reproductive technology (IVF, drugs stimulating ovulation)
6) women who are on the pill are more likely to have multiples (if they do in fact become pregnant by chance)
^ some of these are out of your control though. none make it 100% certain though
oh. I meant to say there's no way to make it certain in my first sentence haha
Make sure the mother has a history of twins in the family. There will be a greater chance she will have twins too. If she gets pregnant via IVR then that procedure produces twins VERY much (and in some cases more than 2 babies). These are the only ways I know about.
I think it is heredity that usually determines that. If not I think 2 sperm can get into 1 egg and then that is possible. But hey what do I know? I don't even know anyone with twins.
Sure. Some fertility drugs can cause this. Also my girlfriend is on some birth control, and her doctors told her that if she suddenly stops it, there's a chance of her getting twins if she got pregnant, as that drug has a history of this. Still no guarantees though.
Anyway you might wanna talk this over with your girl first. then maybe talk it over with a doctor. The stuff I'm saying is just shit I'm repeating. I have no idea what the effects are, or what this does to her. All I'm saying is that I hear it's possible. So talk about it with her and a few doctors first.
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