In adults, normal menstrual cycles occur every 24 to 35 days and last a week or less. Teenagers and women near menopause are
more likely to experience irregular cycles, but a good rule of thumb is that periods should not come closer than three weeks apart and
the bleeding should not last more than eight days.
The beginning of the cycle, called Day 1, is the day bleeding begins. The flow usually lasts about 3 to 5 days. Usually by Day 7 some
of the eggs in the ovaries start ripening. One egg is released from the ovary on about Day 14. The other ripening eggs stop growing
and dry up. The time from menstruation to ovulation, may vary from 13 to 20 days in length from one woman to another, but also
differs in some women from month to month. Such common circumstances as sickness, worry, physical exertion, and even sudden
changes in climate may occasionally upset a regular pattern by shortening it or extending it.
During ovulation the egg travels down the fallopian tube toward the uterus. If a single male sperm unites with the egg while it is in the
tube pregnancy begins. If fertilization doesn't take place, the egg cell will break apart in a day or two. About Day 25, hormone levels
drop. This causes the lining of the uterus to break down and in a few days it is shed in a menstrual period. Another cycle has begun.
This part of the cycle, from ovulation to menstruation, is about the same length in all women. The egg is released consistently 14 to
16 days before the onset of menstruation, regardless of the length of a woman’s menstrual cycle.
Charting the signs of our menstrual cycle is a good way to keep in touch with our bodies, our feelings, and our health. It is also a
good way to predict our days of menstruation in advance, even if menstrual cycles are irregular, and to know the most fertile times if
we are hoping to conceive.
Keeping track of when you get your period each month and knowing how long it is likely to last is certainly practical, as it allows you to
avoid potentially embarrassing or uncomfortable situations by being prepared accordingly - for example, having pads and ibuprofen
But knowing when to expect your menstrual cycle also can provide important information when it comes to figuring out if you are
pregnant, are planning to conceive, or if you or your practitioner suspect a menstrual problem. That's why it's good to get into the habit
of using a menstrual calendar.
Your doctor may want to see a record of your menstrual cycles if there are any concerns about menstrual irregularities or if you are
trying to get pregnant.
Most women have premenstrual syndrome (PMS) symptoms occur in cycles, coming and going at roughly the same time each month. If you are having premenstrual-like symptoms, your health professional may ask you to keep a menstrual diary and to track when your symptoms occur.
Why Do You Need a Menstrual Calendar?
Here are just a few of the reasons why you should have an up to date menstrual diary:
Vacation: Going on vacation would be so much fun if you could plan it for the time when you will not be having your period.
Doctors: When you go to see a doctor he/she would need to know when was your last menstrual cycle. Especially your ObGyn, who
will need to know all the details to determine if there is any problem.
Family Planning: Your fertility periods are determined by your ovulation. And ovulation can be calculated from your menstrual diary. But
you need to have data at least for 6 month. A year is better.
Social Life: If you have heavy PMS you can be prepared and you can avoid problems and conflicts. You can also avoid going to a party
or take a day off.
Sex Life: If you are dating it will be good to choose the appropriate time for a special night according to your fertile and not-fertile days.
See below example of menstrual calendar and empty calendar for free downloading.
10 Things You Need to Know About Periods (from Tina Kells)