It is compulsory on any new Muslim man to get himself circumcised.
Circumcision for him is an obligatory act (Wajib). If he does not
perform this obligatory act, his Tawaaf around the Ka’aba will be
invalid and if he slaughters any animal, that animal will be not be
As far as having children with his Muslim wife, it is permissible in principle, but
his Muslim wife should be sure that he is really a Muslim who does not object
to the rules of Islam.
The Muslim women should be sure about the future of her marriage future with him and should not, God-forbid, have to face unexpected situation that he rejects the rules of Islam.