Basal Body Temperature as a Means To Confirm Pregnancy?

[Aly__0]

  I have been concerned that I am approximately four weeks pregnant, however, my hpts have come out negative.
  My OB-GYN told me take my temperature every  morning immediately upon waking up with a basal body thermometer and if it was over 98 degrees for a coupel of days, I was most likely prengant.
  Is that correct?  Can you explain to me the basal body temp.?
  Also, can your temperature tell you if you are pregnant or not?
  Any info would be helpful.  Thanks.

[hfhs.md.db]

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Dear Ally
All of the responses posted to your question have valuable information about basal body temperature monitoring (BBT). Basically, BBT works because the hormone progesterone (produced by the ovary and later by the placenta)is thermogenic, in other words, it tends to produce a rise in the body temperature of approximately one half a degree Farenheit. Although this thermogenic effect is present all of the time, you measure the BBT first thing in the morning to remove the influence of other daily activities that can alter your body temperature (such as muscular activity, showering, eating, etc.).
Progesterone levels rise after ovulation, in the second part of the normal menstrual cycle. If conception does not occur in that cycle, the progesterone levels start to naturally decline starting around 7-10 days after ovulation. However, if conception occurs, the early pregnancy hormone hCG stimulates the ovary to continue to produce progesterone for 6-8 weeks, at which time the progesterone production is taken over by the placenta.
Therefore, a BBT that does not decline as expected in the second part of the cycle may indicate a conception, as your doctor has indicated. However, it is important to remember that there often is some variability in early pregnancy events. Therefore, I would suggest that you wait until after you have missed an expected menses before testing for pregnancy (with a urine hCG test). In general, urine hCG tests--the home pregnancy test first become positive at about the time you miss your first period.
Hope this helps!