Holy tentacular twins, Batman! This is crazy news, the first study linking the incidence of twins with environmental factors. The culprit is growth hormone fed to cows to increase milk production. According to this Wikipedia article, a third of all dairy cattle use Monsanto’s rBGH (or rBST) brand Posilac®, so obviously, use is widespread.
FEED – July 2006 (from the Union of Concerned Scientists)
1. Engineered hormone in milk may be linked to twinning. A recent study found that women who consumed dairy products were five times more likely to give birth to twins than vegan women. The study suggested that the use of engineered bovine growth hormone/bovine somatotropin (BGH/BST) to boost milk production in dairy cows may be related to the higher level of twinning. BGH is known to increase twinning in dairy cows. In addition, the rate of human twinning is twice as high in the United States, where BGH is used, as in Britain, where BGH is banned. BGH affects twinning rate by increasing insulin-like growth factor (IGF), a protein produced in the milk of both animals and humans, that promotes ovulation and may help early-stage embryos survive. A separate study found that levels of IGF were 13 percent lower in vegan women than in women who consumed dairy products. Read a press release about the study, which was published in The Journal of Reproductive Medicine.
If true, no woman should ever drink “conventional” milk (non-organic, non rGBH free, etc). Twins are fun, I love my twin nieces very much, but they are much more difficult to carry and deliver, and there are more complications.
Scary, but I suspect this is the tip of the iceberg as far as environmental effects on childbirth are concerned.