It's been a long while since I've used birth control pills, and thankfully no longer need to worry about pregnancy. Of all the warnings they give you about possible side effects, I don't recall ever hearing that the "pill" was a "vitamin robber".
I came across this promotion for a book, "The Pill Problem by Ross Pelton" in my email. For those taking the pill, or even considering it, it might be worth reading. Available not only in paperback, but also your electronic devices as well: http://www.naturalpharmacist.net/books/thepillproblem/
The book's intro reads: "Birth control pills are currently taken by over 12 million women in the United States and over 100 million women worldwide. Unfortunately, most don’t realize that taking birth control pills substantially increases the risk of having many health problems, some of which are potentially very serious. In his new book Ross Pelton, the world's leading expert on drug-induced nutrient depletions, teaches how to protect your health from the dangerous side effects of oral contraceptives.
I have no vested interest in this at all. Given our interests, if not obsessions, with well-being and good health, I thought sharing this would be beneficial to many women.