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Q: BBT Temps after Ovulation ( Answered 5 out of 5 stars,   2 Comments )
Subject: BBT Temps after Ovulation
Category: Health > Women's Health
Asked by: tryin41more-ga
List Price: $30.00
Posted: 27 Apr 2006 14:25 PDT
Expires: 27 May 2006 14:25 PDT
Question ID: 723468
FF suggests that I ovulated on CD 13 - my monitor says CD 15. 
According to FF and my temps, I am 14 dpo today.  Up until yesterday,
it suggest a triphasic pattern.  My temps yesterday was 97.92 and
today it dropped down to 97.27.  It was cooler in our room than usual,
so I am not sure if this could have an effect on the temps???  My
coverline is 96.97, so my temps are still above the coverline.  My
question is, since this big drop in my temps, is this a for sure sign
that my period is getting ready to show up???

Thanks for your help!
Subject: Re: BBT Temps after Ovulation
Answered By: boquinha-ga on 27 Apr 2006 21:50 PDT
Rated:5 out of 5 stars
Hello tryin41more-ga!

As a mother myself I can certainly identify with the emotions you must
be feeling now as you contemplate pregnancy. Interpreting the many
things you are feeling and recording right now can get tricky and, at
least for me, EVERYTHING I experienced became a major point to
consider and I found myself researching A LOT! As you know by now, the
internet is FULL of information regarding pregnancy, and it?s hard to
weed through it all. I have tried to pick out the most relevant pieces
of information to your situation and organize it for you.

Some of what I present initially will most likely be things of which
you are aware, but for completion?s sake I have included it. It seems
like in medicine, and the obstetrical world in particular, there are
no ?sure things,? so ultimately you will need to draw your own
conclusions based upon the information you have in front of you. And,
of course, none of the information I am presenting is a substitute for
the advice of your own personal health care provider. With that said,
here we go!

- - - - - - - - - - - - - - - - - - - -


FAM (or natural family planning) involves monitoring body changes that
occur during a menstrual cycle. Ultimately, the most important thing
to identify is the timing of ovulation. Since pinpointing this event
exactly is extremely difficult, you must identify a period of time
during which you are most fertile. To do this monitoring a number of
things is useful. These are:

* Calendar method: Estimating ovulation based upon past menstrual
cycles, with ovulation beginning 14 days prior to menstruation.
* Basal body temperature (BBT) method: The BBT is the lowest body
temperature during the day, usually in the morning before getting out
of bed. The BBT dips slightly before ovulation and rises again 1-2
days after. It then, in many cases, returns to baseline prior to
* Cervical mucus method: The cervical mucus changes in amount and
consistency immediately after menstruation, and then again before and
during ovulation.
* Hormone monitoring: Home ovulation kits can be purchased to test for
hormone levels that change around ovulation.
* Combined (symptothermal) method: This method uses any combination of
the above to increase the accuracy of your prediction of ovulation.

For a more complete description of these methods and FAM see:

Here is more information about FAM.

- - - - - - - - - - - - - - - - - - - -


There are literally dozens of sites out there dedicated to charting
the BBT. is one of which you seem to be aware, but
there are many others. I found a lot of information on the BBT and
have tried to find the information that you will find most relevant
and interesting.

Determining your ?coverline? is an important first step in temperature
charting. Once you observe the slight rise in BBT associated with
ovulation, look over your temperatures over the past 6 days. Find the
highest among those, and draw your ?coverline? here. For more details

While the coverline is a useful tool to help track temperature, it
?carries no physiological meaning. . . .It is just a visual tool to
help you see your ovulation pattern.? Don?t make a judgment based upon
one temperature reading?observe the ?big picture? and look for trends.

?A minimum temperature [BBT] rise of 0.4 to 0.6 degrees F can be
measured [just prior to ovulation] - and this change will last through
the duration of the menstrual cycle. By monitoring when this
temperature change takes place, you can estimate when ovulation has
taken place.?

?When a woman ovulates, progesterone is released into the body. One of
the effects of this hormone is to slightly raise your waking
temperature, typically by about 0.2 to 0.4 Fahrenheit / 0.1 to 0.2
Celsius over several days.?

?Triphasic temperature patterns are often indicative of implantation
during a cycle and may occur before a home pregnancy test can return
positive results. They are called triphasic because they represent a
third level of high temperatures typically reached seven to ten days
after ovulation. (The first level of temperatures are those preceding
ovulation, the second level of temperatures are those immediately
after ovulation, the third level of temperatures are those after

While a triphasic temperature pattern is a promising sign, its
presence is not absolutely indicative of pregnancy, and its absence
doesn?t absolutely rule a pregnancy out.

?A triphasic chart shows three levels of temperatures: pre-ovulation,
post-ovulation, and then a second rise around 7-10 days after
ovulation. Some women with charts that show this pattern turn out to
be pregnant. But many do not. Likewise, your chart does not need to
show this kind of pattern for you to be pregnant. . . . A triphasic
chart can be promising, however, because progesterone levels generally
increase after implantation (7-10 days past ovulation) in conception
cycles, and sometimes this results in a triphasic pattern. . . . A
triphasic chart, however, is not a definite sign that you are or are
not pregnant. It is just increasing your probability if you also have
well-timed intercourse. Likewise, you can be pregnant and not have a
triphasic pattern. Like all signs of possible implantation or
pregnancy, you can really only speculate about it once a pregnancy has
already been confirmed.?

How?s that for clarity!

On a number of sites, I found that 18 days of elevated temperatures
seems to indicate that pregnancy is likely.

Your temperature will drop again either just before or on the day that
your period starts, and a run of 18 temperatures above the coverline
will indicate that you are pregnant.?

?If your temperature has remained above your coverline for 18 or more
days, you are most likely pregnant.  Rarely, a corpus luteum cyst will
cause elevated temperatures in a cycle where conception did not occur.
 It is important to make sure you knew exactly when ovulation and the
thermal shift occurred so the count will be accurate. Not all women
ovulate on Day 14!?

?If pregnant, the temperatures will stay high. The rule for pregnancy
is 18 days of high temperatures indicates pregnancy. Usually when the
menstrual cycle is due the temperatures may start to drop down a day
or so before the bleeding starts.?

- - - - - - - - - - - - - - - - - - - -


As you?ve astutely observed, a drop in BBT or a return to your
coverline or baseline may indicate that menstruation is likely. Like
I?ve said before, however, ?more likely? does not necessarily equal

?The body temperature drops immediately before ovulation and rises 0.5
- 1.0c after ovulation, which is maintained for the remainder of the
cycle. The temperature then falls back before the menstrual flow

?Post-ovulatory temps will remain high for a period usually 12 to 16
days until they drop again when your cycle ends and menstrual period

Elevated BBT readings ?will last until the temperature drop that
usually comes just before the onset of your next menstrual period.?

?If you see a low temperature around the time you would expect your
period, your period is usually on the way. In most cases, you will see
your period sometime that same day or the following day. If it is not
yet close to when you would expect your period, then it is still too
early to tell. A single temperature during your cycle rarely carries
much meaning on its own. You are looking for patterns and trends on
your chart and to do this you need to look at several temperature
points along with your other fertility signs.?

I think that the key is really contained in the last sentence in that
last quote. Look for patterns along with other signs and try to avoid
making ?snap judgments? based upon one lower temperature alone.

- - - - - - - - - - - - - - - - - - - -


There are a number of factors that can affect your BBT, mostly by
causing it to rise. Some of those are:

* fever
* illness
* some medications
* alcohol
* smoking
* stress, emotionally and physically
* sleep disturbances
* travel
* jet lag
* change of climate
* electric blankets
* change of room temperature

There are a number of others listed at:

Notice that room temperature is a factor. Whether or not a lower room
temperature can cause a lower BBT is not certain, however.

?It is important to realize that your BBT can be influenced by other
factors such as physical or emotional upsets, lack of sleep, illness,
emotional distress, jet lag, disturbed sleep, smoking, drinking
alcohol the night before, or using an electric blanket.?

The following site has a similar list. It also mentions that ?if you
have a sudden dip in temperature it is more likely to be a recording

- - - - - - - - - - - - - - - - - - - -

So, after all of this, the answer you is that there is no ?sure? way
to predict whether or not this dip in temperature is signaling the
onset of menstruation. One big thing favoring a pregnancy is that the
dip is still technically elevated above your coverline. Patterns are
important, too, and it seems that your BBT is still elevated enough to
continue your ?18-day count.? Most of all stay positive and try not to
interpret any one sign as an ?absolute? indicator.

I sincerely wish you much success. Researching and writing this answer
for you has me thinking about times I?ve gone through similar things
myself. I know that it can be very stressful (and even trying to not
stress can be stressful!) and emotional. To long for something so good
so much can affect you greatly--physically, spiritually, and
emotionally. I truly wish you great success and happiness . . .and
soon! If you have need of further clarification, please let me know
how I can help.


Search terms:

predicting ovulation
triphasic pattern temperature
temperature drop menstruation
coverline before menstruation
factors affecting bbt
low room temperature bbt
factors affecting bbt
tryin41more-ga rated this answer:5 out of 5 stars and gave an additional tip of: $5.00
I was highly impressed.  A lot of research went into this answer.

Subject: Re: BBT Temps after Ovulation
From: boquinha-ga on 28 Apr 2006 07:45 PDT
Thank you very much for the 5-star rating and the kind words. I wish
you much success--I really do.

Subject: Re: BBT Temps after Ovulation
From: boquinha-ga on 28 Apr 2006 10:20 PDT
My apologies--I meant to thank you for the tip, too. I really
appreciate that very much.

Best wishes,

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