Basal Body Temperature During Pregnancy

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Basil body temperature is the temperature of a woman’s body while at rest. Many people are aware that charting basil body temperature (BBT) is an important and helpful method of helping a woman determine when she is going to ovulate, thereby optimizing the best chance for pregnancy.

To make sure the BBT is accurate a woman should:
• Use a basil body temperature thermometer. These are inexpensive and can be purchased at any pharmacy.
• Take her temperature each morning at the same time as soon as she wakes up after having slept at least four hours.
• Take her temperature before she gets out of bed, eats, drinks, smokes or uses the bathroom.
• Use a BBT chart to record her temperature everyday starting with the first day of the menstrual period.

A woman’s BBT will drop just prior to ovulation signaling when she is most fertile. A woman should continue to take her basil body temperature every day for the rest of her menstrual cycle. If she is not pregnant she should start a new BBT chart on the first day of her next period.

One thing a woman should look for as she continues to take her basil body temperature after ovulation is the implantation dip. This is usually a one day dip that occurs about a week after ovulation. The phase of the menstrual cycle between ovulation and the next period is the luteal phase. Implantation of a fertilized egg usually occurs between day 7 and 11 of the luteal phase.

Further, basil body temperature can be one of the first indicators that a woman is pregnant. Basil body temperature remains elevated when pregnancy has occurred. If basil body temperature remains elevated for 18 days after ovulation, a woman should consider taking a pregnancy test.

Remember that basil body temperature measurement is not an exact science. It may take a couple of menstrual cycles to get the hang of charting BBT. If, after six months of consistently taking BBT and having intercourse at the optimal time, pregnancy does not occur, it might be time to seek the help and advice of a fertility specialist.


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