Does divorcing with the words "you are divorced" three times in one sitting, with the intention of a single divorce, constitute three divorces? And does having intercourse with one's wife after she becomes pure and before the divorce affect the validity of the divorce?

1. A man divorcing his wife during a period of purity in which he had intercourse with her is an innovated (bid'i) and forbidden divorce. The correct view is that it does not take effect. 2. The preponderant opinion regarding a triple divorce is that it counts as a single divorce, whether uttered in one phrase or in separate phrases in a single session or in successive sessions not interrupted by a return (raj'ah) or a new marriage contract. This is the choice of Shaykh al-Islam Ibn Taymiyyah and those who followed him, and they based their evidence on what Muslim narrated from Ibn Abbas, may Allah be pleased with them both.

Based on the foregoing, if your divorce of your wife occurred during a period of purity in which you had intercourse with her, then it does not take effect.