Ibrahim (may Allah have mercy on him) said: "If someone has taken an oath of abstinence (ila) from his wife, and the woman is not able to have intercourse due to menstruation, postnatal bleeding, or any excuse, then the husband should announce his return; she will remain his wife."
Hadith Referenceسنن سعید بن منصور / كتاب الطلاق / 3074