The males need to be seperated from the females asap although the females may already be pregnant. Good breeders do not leave different sex pairs together all of the time although it does not often occur to the general public to seperate them. Chinchillas have a major hereditary problem called Malloclusion where the root of a tooth may contoinue to grow and grow causing death eventually. Good breeders try to only breed from Chins whose history is known and then only from non-maloccluding lines. Malloclusion may sometimes be detected by an expert examining the jaw but more often that not an xray is required. The baby should be removed at 8 weeks if it is a male and can normally be placed with an adult male. He can then be rehomed at about 12 weeks old. If the males are neutered they will still need to be apart from the females for 6 weeks and even then, only one neutered male can be kept in a cage as they will still fight other neutered or un-neutered males in the same cage.

Just one cage will not be a possibility with more than one male for the reasons stated previously. I have 2 neutered males. One lives with 3 females and the other lives with 2 females. Introductions between chins who have never lived together before can also be fraught with difficulties unless you know how to do it. Here is a website to help you further. (It also has an excellent forum to join where they will help you further) Chinchilla World