Premenstrual syndrome (PMS)

Menstrual cycle calendar

If you want to learn more about your own body and be able to predict when you are most fertile, you can use a menstrual cycle calculator to do so. It will help you to either encourage or avoid pregnancy, whatever your aim is. Besides, knowing when your next period is expected can also be very useful for making many decisions – for example, for scheduling a vacation.

First of all, get some graph paper, which will carry your temperature diagram. Make the vertical axis the temperature reading by writing on it the numbers from 97.5 to 99.5, including each 1/10 of a degree. The horizontal axis, at the very bottom of the graph, will represent the days in your cycle, so you need to write the numbers from 1 to 28 or some more if your cycle continues longer than 28 days. The current day will be the top horizontal axis.

Start charting your menstrual cycle from the 1st day of your period. That first day will represent cycle day 1. In order to indicate that you are menstruating, put a letter “M” under the numbers on the horizontal axis. Keep doing this every day you have your period within the current cycle.

Start taking the oral temperature by day 2 of your cycle. This should be the first thing to do in the morning, after at least 6 hours of sleep, at the same time each day (even weekends!), just after you woke up and before you get out of bed – even before going to the bathroom! You will need to use a basal body temperature thermometer for measuring your basal temperature, because a regular thermometer for reading a fever may be not sensitive enough. You can get a special basal body temperature thermometer at almost any drug store or pharmacy.

After measuring your temperature, draw a dot next to the number on the vertical axis corresponding with your temperature result. Make sure this dot is also in line with the current cycle day number and date written on your horizontal axis. Repeat the procedure every day. As the days go by, connect your dots with a straight line to receive a graph.

Somewhere at the middle of the cycle you will determine your ovulation day. When you see a rise of about 0.4F in your body temperature which sustained itself for at least three days, it will mean that you had probably ovulated right before the 1st temperature rise. Now you need to go back in your chart and mark the day before the first temperature rise by brightly colored crosshairs.

After ovulation, you may expect your period to arrive in somewhere between 10 to 16 days. The phase of your cycle lasting from ovulation day to first menstruation day is called “luteal”. It is normally consistent each cycle for the same woman, which means that after you have drawn your basal temperature graph for a few months, it will show you how long your luteal phase will last each month.