Musannaf Ibn Abi Shaybah

Hazrat Ash'ath (may Allah have mercy on him) narrates that Hazrat 'Amir (may Allah have mercy on him) and Hazrat Hakam (may Allah have mercy on him), both of these personalities, stated: If a Muslim apostatizes from Islam and goes to the land of the enemy, both of them said: If his wife experiences menstruation, she will observe a waiting period ('iddah) of three menstrual cycles. And if she does not menstruate, she will observe a waiting period of three months, and if she is pregnant, her waiting period will be until childbirth. Then the inheritance of this apostate will be distributed among his wife and Muslim heirs. Then, if the woman wishes, she may marry. And if the apostate returns and repents before his wife's waiting period is completed, then both of them will remain upon their previous marriage.

Hazrat Sha’bah (may Allah have mercy on him) narrates that Hazrat Hakam (may Allah have mercy on him) said regarding the man who becomes a polytheist and goes to the land of the enemy: his wife cannot marry another man. And Hazrat Hammad (may Allah have mercy on him) said: his wife can marry.