Basal Body Temperature (BBT)
Many women are interested in tracking their basal body temperatures when getting ready to conceive. Basal body temperature refers to the temperature of your body when it is at rest. Slight changes in this temperature can help you determine when you are ovulating. This can help you increase your chances of becoming pregnant by helping you select the optimum time during your menstrual cycle to have intercourse.
Start by preparing a chart to keep track of your daily findings. It is very important that you take your temperature before you get out of bed in the morning. Take it as soon as you wake up and try not to move around. It is easiest to keep up with your daily temperature if you keep the thermometer and chart next to your bed. Make it part of your morning routine.
Many women start charting their basal body temperature around the first day of their menstrual period. If you are ovulating normally, then you should see a change around day fourteen of your cycle (in a 28-day cycle), day one being the first day of your period. You may see as little as a 0.4 degree change and it should stay at this point for a few days. During this time of higher temperature is when you can assume that ovulation has taken place. You may even notice a slight drop in temperature the day before the rise.
Hormone levels and changes are what cause your basal body temperature to change. The initial rise in temperature usually occurs the day after ovulation. Your best chances of getting pregnant are the few days before and the day of ovulation. Therefore, you need to determine when your body temperature rises and calculate when it will happen again. Have intercourse during the five days leading up to the temperature rise. Sperm can live for up to 72 hours (and even as long as seven days) inside of your uterus, so having sex before ovulation will help eunsure that your egg will encounter the sperm.
If you are trying to avoid pregnancy, then you should abstain from sex for about a week prior to ovulation. Be aware that many things such as lifestyle, medications, illness, environment and diet can change the day that you ovulate. Only women with extremely regular menstrual periods have been successful in using basal body temperature and ovulation timing as a form of birth control. Even then, there have been quite a few surprises.