What is the ruling regarding someone who had intercourse with his wife a few minutes before the Fajr athan, and continued the intercourse after the athan?

One must abstain from all things that break the fast from the rise of true dawn until sunset, based on the Almighty's saying: ﴿And eat and drink until the white thread of dawn becomes distinct to you from the black thread [of night]﴾. So, whoever is certain of the rise of dawn must abstain. If one was engaged in intimacy and withdrew immediately, their fast is valid. However, if they continued after knowing that dawn had broken, their fast is invalid, and they must make up the day and offer expiation. If their wife was compliant, the same applies to her. But if she was coerced, her fast is valid.

If the adhan relies on the sighting of dawn, one must withdraw immediately upon hearing the adhan. If intimacy continues, the fast is invalidated, and both making up the day and expiation are required. If one withdrew but continued with foreplay until ejaculation, the fast is invalidated, and making up the day is required, but not expiation.

If the adhan relies on clocks and calendars, and intimacy continued for a short period after the adhan without certainty of dawn breaking, the fast is valid. However, it is preferable to be cautious and abstain upon hearing the adhan.