All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
It is not permissible for a Muslim woman to marry a non-Muslim man as Allaah Says (which means): {And give not (your daughters) in marriage to Al-Mushrikeen till they believe (in Allaah Alone) And a believing slave is better than a polytheist, even though he might please you. Those invite [you] to the Fire, but Allaah invites to
As regards circumcision, it is one of the best legislations that Allaah legislated for His slaves, and with it He beautified their apparent and hidden charms. It is one of the natural dispositions upon which Allaah created mankind. In addition to this, circumcision has many medical advantages. Furthermore, it is scientifically proven that the white secretions that gather between the foreskin of the penis and the penis cause a continuous scratch to the skin of the penis and to the neck of the womb of the woman with whom this uncircumcised man is married. This continuous scratch causes many diseases to the penis and to the neck of the womb of the wife, like cancer and the like. Nonetheless, circumcision is something secondary for a person who has not yet embraced Islam. Therefore, we advise you to embrace Islam so that you will achieve happiness in this life and the Hereafter and to save yourself from a severe torment on the Day of Judgement. For more benefit and information about Islam, you could refer to Fataawa (plural of Fatwa): 81979, 88906, 88276, 88176 and 89563.
To conclude, if you embrace Islam, it is permissible for you to renew the marriage contract with your wife after her observing a waiting period as she could be pregnant from the illegal sexual intercourse that had taken place between you and her [Because in case she is pregnant, you can not establish a marriage contract with her unless after giving birth to the child]. Then, it will be desirable for you to undergo a circumcision if this does not cause any harm to you.Allaah Knows best.