I've studied Christian polygamy for some time. It's definitely not prohibited, although I would say the less wives the better if possible. In some scenarios polygamy is beneficial, and certainly should be practiced instead of divorce, which is horrible and sadly commonplace. It's obvious God created polygamy for a purpose, and I hope more people will educate themselves about it rather than judge. Here is a helpful page that supports Christian polygamy using scripture:

http://www.modernpolygamy.com/polygamy-is-biblical/