However, I want to make a small quibble with one bit in this blog. You say that ovulation “occurs precisely at the start of week three of the cycle” and this is most certainly NOT the case for all women. The perfect 28-day cycle is a myth. I don’t know whether every woman’s cycle “should” be 28 days exactly with ovulation occurring precisely at day 14. Maybe that’s how it is for everyone when hormones are in perfect balance. But that isn’t the reality. I ovulate around day 20-23 (and have ~35 day cycles) and some women ovulate around day 10-12.
Birth control pills are often prescribed to regulate hormonal acne. Generally, acne that occurs around the jaw line is hormonal. However, the best way to figure out whether or not hormones are responsible for your acne is to keep a diary of your breakouts. Track them for a good 3 to 4 months. If you start noticing a pattern, such as breaking out during ovulation (14 days after you get your period), before you get your period, or after you get your period, then your acne is probably hormonal. You can also get your hormone levels checked to make sure they are normal.