[ondry]

to determine your next menstrual period..where do you start counting? from when your first bleeding arrive the last month or from when the bleeding stops? Thanks

[jns]

From when the bleeding starts.

[midnightwishes]

From when the bleeding stops, since it's never the same.

[jns]

From Wikipedia: "By convention, the length of an individual menstrual cycle in days is counted starting with the first day of menstrual bleeding."
From womenshealth dot gov under "The Menstrual Cycle": "Day 1 starts with the first day of your period."
womenshealth dot gov is from the Office on Women's Health, U.S. Department of Health and Human Services

If you use a non-standard convention, make sure you explain it completely when talking with a health professional who uses the standard convention.

[Romy]

Definitely on the day I start bleeding.

[chaya]

Mine is so irregular that it don't do much good to count. It is around every 4 weeks, plus or minus a week. Sometimes very light, sometimes very heavy or sometimes nothing at all. It is either, only having one ovary of maybe a diabetes thing. I've tried BCPs to regulate them but they made me feel like crap so I just live with it.