Charting Your Fertility Pattern-BBT Charting

Knowing when you re most fertile will help you plan a pregnancy. (Not useful as a birth control method). There are three ways you can keep track of your fertile times. They are: basal body temperature method, the calendar method and the cervical mucus method. Below is information on the basal body temperature method. Also print your own Basal Body Temperature Chart to track your ovulation. View a sample BBT chart.

Basal body temperature method - Basal body temperature is your temperature at rest as soon as you awaken in the morning. A woman s basal body temperature rises slightly with ovulation, and remains elevated throughout the remainder of her cycle. So by recording this temperature daily for several months you ll be able to predict your most fertile days.

Basal body temperature differs slightly from woman to woman. Anywhere from 96 to 98 degrees orally is average before ovulation. After ovulation most women have an oral temperature between 97 and 99 degrees. The rise in temperature can be a sudden jump or a gradual climb over a few days.

Usually a woman s basal body temperature rises by only 0.4 to 0.8 degrees Fahrenheit. To detect this tiny change, women must use a basal body thermometer. These thermometers are very sensitive. Most pharmacies sell them for around $10. You then record your temperature on a special chart (a BBT Chart). See our pages on BBT Charts.

The rise in temperature doesn t show exactly when the egg is released. But almost all women have ovulated within three days before their temperature spikes. Once you notice the temperature spike, ovulation has already occurred. Your body temperature stays at the higher level until your period starts.

You are most fertile and most likely to get pregnant: two to five days before your temperature hits the highest point. The best time to try to conceive is starting 2-3 days before you expect ovulation because & A man s sperm can live for up to three days in a woman s body. The sperm can fertilize an egg at any point during that time. So if you have unprotected sex a few days before ovulation, this is the time when you have the greatest chance of becoming pregnant.

Many things can affect basal body temperature. To get the most useful chart you should take your temperature every morning at about the same time. You should avoid doing anything before you take your temperature. Things that can alter your temperature include:

drinking alcohol the night before smoking cigarettes the night before getting a poor night s sleep having a fever doing anything in the morning before you take your temperature  including going to the bathroom and talking on the phone, or having a glass of water.

To most accurately track your fertility, use a combination of all three methods (BBT charting, calender & cervical mucus methods). This is called the symptothermal method.

This information is supplied by The National Women s Health Information Center. The National Women s Health Information Center is Sponsored by the Office on Women s Health in the U.S. Department of Health and Human Services.