Some basic knowledge about menstrual cycles:
⭕ A menstrual cycle is an "ovulatory cycle," in which ovulation is the main event.
⭕ Most other types of bleeds are either pill-bleeds or anovulatory cycles (breakthrough bleeding), such as what happens with PCOS, and on the implant, injection or mini-pill.
⭕ You can confirm ovulation by tracking basal body temperatures.
⭕ Ovulation comes first and then a period almost exactly two weeks later.
⭕ If you're not ovulating, but still having "periods," then you are having anovulatory cycles.
⭕ If you're not having bleeds, then you have either not ovulated or you're pregnant.
⭕ When you come off the pill, you can become pregnant without ever seeing a bleed because ovulation comes first and THEN the bleed. That's why you need to take some action to avoid pregnancy - barrier or withdrawal - even when you have amenorrhea (no periods).
⭕ It's (usually) not possible to ovulate but then not get a period or be pregnant. (The main exception is the hormonal IUD which can let you ovulate but not bleed.)
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