If your cycles last 35 days or longer, you probably ovulate at day 21 or later. Most women who have longer cycles also have irregular cycles, which means the length between their periods varies from month to month. They also may not ovulate at every cycle.

How late can you ovulate in a cycle?

Ovulation lasts only a few hours and usually happens between day 11 and day 21 of the cycle, depending on the length of the follicular phase that preceded it. Ovulation is considered late if it occurs after day 21 of your menstrual cycle.

Does a long period delay ovulation?

According to the Office of Women's Health, the average length of a menstrual cycle is 28 days, but some cycles may last between 21-38 days. People with more prolonged or irregular cycles tend to ovulate later, or they may not ovulate every cycle.