Must the husband renew the marital contract after khalwah (valid seclusion) without consummation, if the wife apostatizes and then repents during her iddah (waiting period)? And what is her prescribed iddah if her menstruation only occurs by taking pills? And does a new iddah begin if the same mistake is repeated during the first iddah?

The valid seclusion [between a husband and wife] is equivalent to consummation. A woman with whom consummation has occurred is obligated to observe the waiting period ('iddah (definition)), and the husband has the right to take her back during this period after a divorce.

In the case of apostasy, the marriage contract is annulled. If the woman repents during the 'iddah, she remains married. If she repents after the 'iddah, a new contract is necessary.

Not all sins are expiated, but some are. Apostasy is one of the sins that Allah Almighty does not forgive; it nullifies good deeds and necessitates eternal residence in Hell if a person dies upon it.

The waiting period ('iddah) is three menstrual cycles for a menstruating woman, even if the cycles are spaced out due to medication or other reasons, and three months for a woman who has reached menopause or has not yet menstruated.