While the science is still being processed on this one, and the verdict is still out, it is believed that diet could also play a role in the conception of twins. Certain foods may contain higher levels of hormones that act similarly to estrogen,. Yams are known to contain these estrogen-like hormones. If a woman eats a lot of yams, it is thought that all that yam eating may may influence her ovulation and conception.
Also, a study performed by Gary Steinman, MD of the Long Island Jewish Medical Center in New York, found that women who eat a diet rich in dairy and animal protein prior to becoming pregnant are also more likely to conceive twins. He found that when he compared the twin birth rate of Vegan Moms, who do not eat animal products or dairy, to those Moms that consumed these products, the milk and meat consuming moms were five times more likely to have twins over the Vegan moms.
So we figure, if you are hoping to have multiples, you should
1. move to Massachusetts
2. try to get pregnant in July
3. try to get pregnant after your 35th birthday
4. and start eating and drinking lots of yams, beef, ham and milk.
Good Luck! :):):):)
Some of our great facts came from - http://baby.lovetoknow.com/wiki/Genetic_Research_of_Identical_Twins