Progesterone, Ovulation & BBT Charting
Conception Process >> Progesterone, Ovulation & BBT Charting
What is Progesterone?
estrogen, progesterone is a major reproductive hormone that plays an important
role in a woman's menstrual cycle. It triggers a number of physiological effects
central to female fertility and to getting pregnant.
Progesterone is manufactured
by the corpus luteum. The corpus luteum (or "luteal body") is what
remains of the collapsed ovarian follicle once ovulation takes place. Once the
egg is released by the ovarian follicle into the fallopian tube, the ovarian
follicle becomes the corpus luteum and begins to release progesterone
into a woman's system.
Following ovulation, this
increase in progesterone helps further build the uterine lining during the endometrial
"secretory stage". The reproductive function of this process is to
prepare the uterus so that a fertilized egg can successfully implant (bind to
the mother's womb). In addition to supporting this process of implantation,
progesterone may provide additional "pregnancy help" by reducing the
chances of contraction in the uterine muscles, as well as by briefly inhibiting
female immune response so that a pregnancy is accepted by the body.
During the first half (or
preovulatory phase) of a women's cycle, progesterone levels remain relatively
low. Following ovulation (the luteal phase), however, the amount of progesterone
will increase to help support the implantation of a fertilized egg in the uterus,
as well as help maintain a pregnancy by preventing menstruation. Progesterone
will also cause a marked warming of the body that is detectable (and measurable)
through the technique of basal body temperature charting (read more in the next
section on this). Progesterone levels will remain high during your pregnancy.
If you do not become pregnant
during a given menstrual cycle, progesterone levels will naturally decrease
late in the cycle, leading to the breakdown of the endometrium and culminating
in menstruation. If on the other hand a pregnancy is achieved, another
hormone will be released by the placenta (hCG), which triggers the corpus luteum
to continue the production of progesterone. Thus, the pregnancy will
be "maintained" and you will soon experience one of your first exciting
pregnancy symptoms - a missed period.
and Miscarriage: As progesterone is central to supporting a
pregnancy, a deficiency in the production of this hormone may also be a contributing
factor in some miscarriages, as well as in "chemical pregnancies"
(situations in which a pregnancy is very briefly achieved though ultimately
not maintained and menstruation ensues). In the case of a miscarriage, your
doctor will be able to provide more information on causes and/or be able test
for any kind of deficiency in progesterone. In addition, there are treatments
for this issue - from progesterone creams to prescription medications and even
natural solutions like acupuncture.
A luteal phase defect may
indicate potential issues with progesterone production. A luteal phase defect
is typically indicated by a very short (imbalanced) second half of the cycle.
By BBT charting, you can determine the length of not just your entire cycle,
but also your luteal phase - which should have a duration of ten days or more.
To read more about luteal phase defects,
and BBT Charting: The easiest way to see how progesterone "drives"
your bbt chart is to look at the graph above (which displays changes in hormone
levels through a hypothetical 28-day cycle). The two lines of interest for our
purposes here are the green line (progesterone) and the gray line (your
basal body temperature) - and their relational correspondence. Note how
both body temperature and progesterone "lay low" for the first 14
days of this cycle. The reason for this is because the ovarian follicle has
not yet released the egg and the cycle is governed thus far by the estrogens.
However, on Cycle Day 14,
the egg is released and the ovarian follicle assumes a new and colorful role
on the reproductive stage as the corpus luteum. Progesterone production commences
and, about a full day after you ovulate, your body temperature rises along with
the elevated levels of progesterone (which is the very cause of this "heating
up"). Progesterone - and body temperature - remain relatively high through
the rest of the cycle, though if you do not become pregnant, both will gradually
decrease and ultimately menstruation will take place on Cycle Day 28. If pregnancy
is achieved, the corpus luteum receives a hormonal message to keep manufacturing
progesterone and temperatures stay high.
BBT charting requires that
you start taking your basal temperature on Day 1 of your cycle - which is defined
as the first day of menstrual bleeding. Take your temperature every
day and record on a graph chart. Your graph should follow a similar (but by
no means exact) diagram as the image below. Most educational resources on human
reproduction take the twenty-eight day cycle as an example because it represents
an average. Your cycle may, of course, be longer or shorter and fall within
a normal range.
In order to
extract precise fertility information from your chart, you must be exacting
in your BBT Charting methodology. There's no room for error - so be
rigorous in your charting practices. That is to say, please observe all the
guidelines and instructional pointers to ensure you are tracking your body temperature
with precision and garnering the facts you need to predict when you ovulate.
Easier said than done at, say, 5 AM in the morning... However, a well-kept bbt
chart can reward you with a wealth of information and increase your chances
refers to your resting or base temperature at the minute you wake up in the
morning. Take your basal temp immediately upon waking - after at least four
to five hours of sleep (do not get up, go to the bathroom, drink water, etc,
just roll over, take your thermometer off the nightstand, and place in mouth).
Once you get a reading, write it on the chart. To learn more about the details
of keeping an ovulation calendar and comprehensive fertility
chart, click here.
To learn more about special
basal thermometers designed especially for fertility purposes, click here.
Can BBT Charting Can Tell Me?
- The (average) length
of your menstrual cycle. Not only will you discover the length of your
cycle, you will also find out if your cycle is regular or irregular. These
are very important details when it comes to conceiving a baby.
- Phase Info:
The length and duration of the phases of your cycle - the preovulatory phase
and the luteal phase.
- Fertility issues....
If either cycle phase is out-of-balance (e.g., you chart a shortened
luteal phase), you can be alerted to possible issues like hormonal imbalance
(often associated with the regulatory relationship between the estrogens and
progesterone). Cycle irregularity or the failure to detect bbt thermal shifts
(temperature increases) can also indicate hormonal or physiological issues
that may require the assistance, council, or treatment of your doctor.
- When you ovulate!
By keeping a bbt chart, you know the day you ovulate and you can apply
this information to predict fertility for future cycles. A bbt thermal shift
takes place about a full day after you ovulate, so it cannot help
you predict ovulation for the cycle you are in at the present moment. But
by charting patterns, you can pinpoint your fertile window with accuracy for
following cycles. If
you know when you ovulate, you know when to time lovemaking to increase your
- Am I Pregnant?
In principle, bbt charting can provide you with an early pregnancy sign if
your temperature does not decrease in accordance with previous cycle patterns.
This might indicate that you progesterone levels are staying high due to implantation
of a fertilized egg.
- To learn about predicting
fertility based on related changes in cervical
fluids, click here.
More on BBT Charting
Our TTC FAQ
Week-by-Week Early Pregnancy Adventure