How to BBT
Conception FAQs >> How to BBT
Question: What's involved in BBT Charts? And how do I take a "basal"
Your BBT Chart is the anchor of your ovulation calendar, the archimedean
point for knowing the best time to get pregnant. That's because, by bbt
charting you are doing two smart things: First, you are confirming that your
cycle is healthy and that you are indeed ovulating each month. Secondly, by
knowing when you ovulate each cycle, you can accurately determine when
you will likely "O" in the future. As a corollary of these two functions,
if you have cycle irregularities, hormonal imbalances, or potential infertility
obstacles, a bbt charting record may alert you to certain issues and can certainly
help your doctor gain better insight into possible diagnoses or treatments (including
the use of fertility drugs or supplements).
The whole point of bbt charting is to measure an increase in body temperature
that takes place about 48 hours following the moment you ovulate. Once the egg
is expelled from the follicle/corpus luteum, the luteal body that once hosted
the egg starts to manufacture an important reproductive hormone called progesterone.
One of the effects of this surge in progesterone is the "heating up"
of your entire organism - and this thermal shift is quite measurable using a
basal thermometer. In most cases, women will detect a temperature increase of
typically between 0.4° F and 1.0° F, though it could
be a bit more. This rise is indicative that ovulation has just taken place as
progesterone will not be produced in volume until the ovum leaves the ovarian
How do take my BBTs?
The only part that's a drag about taking your bbts is that you have
to do it the very first thing in the morning. And by the very first thing, I
mean the very first thing - no moving around, no peeing, no drinking
water, no getting out of bed. Your special basal thermometer should be next
to you on your nightstand, ready and waiting. Basal refers
to the word base, or baseline, so this means your base temperature
before getting up, a kind of standardized thermal benchmark, if you will. Also,
you need to be coming off a fairly decent night's sleep - at least four hours
worth of solid shut-eye. In a sense, your body starts the day "calibrated"
for a bbt measurement. Ideally, try to take your bbts at the same time every
morning. The minute you wake up, pop the thermometer in your mouth and take
a reading. Don't drink, eat, pee, brush teeth - or anything - until you have
established your day's bbt result.
You'll need a special
bbt thermometer that displays changes of 1/100 degree. We have these
available here at Early-Pregnancy-Tests.com. Once you start with one thermometer,
do not use another! Its the relative accuracy of one thermometer that
tells you what you need to know. Absolute accuracy, while fine and dandy, is
less relevant than relative accuracy - because its the relative changes you
monitor throughout your cycle that tell you when your thermal shift takes place.
The biphasic bbt
chart: A biphasic bbt chart represents the before and after
of ovulation, so to speak. Imagine a simple graph that represents
each day of a hypothetical 30 Day menstrual cycle. Cycle day 1 is designated
as the start of your period, the first day of menstrual bleeding. Given a 30-day
cycle, the first 15 days of your bbt chart will display a flat line
composed of lower temperatures (relatively speaking). This is the cool,
estrogen-dominant phase of your menstrual cycle. Once you ovulate (let's say
on cycle day 15), you should see a stark and definitive temperature increase
- a spike in the line - with you bbt temps shooting upwards
like stock-market numbers during the dot-com boom. The temperature spike should
last just a few days and then your line will flatten out up there at a higher
temperature for the rest of your cycle. That's because the corpus luteum will
continue to manufacture progesterone during the hot phase of this cycle, the
15 days after you O. If you do not achieve a pregnancy, you can expect to see
your hot phase temps cool down around the time of your period. Once you experience
menstrual bleeding, you'll know that this particular cycle is over and its time
for a new cycle day one!
The BBT thermal shift will be measurable about a day after you ovulate. In effect,
your thermal shift does not predict when you ovulate, it only confirms the fact
after the fact. So, your temperature increase will come a day or so
after ovulation. Your bbt chart, then, is not an ovulation prediction device
in the formal sense of the word; what it does provide however is a more general,
wide-angle perspective on your cycle and menstrual/fertility health.
BBT Charts and Pregnancy:
In the case of pregnancy, the hormone hCG will tell the corpus luteum to keep
pumping out the progesterone. In the case of pregnancy, it is theoretically
possible to detect that you have conceived if your bbt temps stay high or do
not fall when you typically expect them to. Following implantation, for example,
the bbt line may dip slightly and then rise again. This could indicate you are
pregnant. That said, there are many variables when it comes to bbt charting
and many vagaries and vicissitudes as to when and how fast your bbt temps drop,
so many TTC experts do not promote using your bbt chart as a pregnancy test.
Better to pee on a stick.
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