Lesson
2: Initial Testing and Diagnosis
Blood Tests - Which Ones and When
In
Lesson 1, section 8 - The Infertility Exam, we glanced at which
blood tests should be ordered and on which day of the woman's cycle
they should be ordered on, but we did not go into any kind of details
about them. That is what we will do here, explore each blood test,
and when it should be done. Let's start by looking at the tests
that should be done on Cycle Day 3 first.
- Estrogen
- LH
- FSH
- Prolactin
- TSH (Thyroid Stimulating Hormone)
Estrogen,
LH, and FSH levels are read together to determine if there is an
ovulatory problem. The 'normal' levels for each hormone will vary
from lab to lab, but the averages are:
- Estrogen – 25 to 75 mIU/ml
- LH – 7 mIU/ml or less
- FSH – 3 to 25 mIU/ml
- Prolactin – 24 ng/ml or less
- TSH - .4 to 4 mIU/ml
The
following are tests that should be done 7 to 10 days after ovulation,
or that can be performed at any time during the woman's cycle.
- Progesterone
- Total Testosterone
- Free Testosterone
- Androstenedione
Progesterone,
testosterone, and androgen levels should also be evaluated in conjunction
with the results from the cycle day 3 tests. As with the other hormone
tests, the 'normal' levels will vary from lab to lab, but the averages
are:
- Progesterone (7 to 10 days after O) – 10 ng/ml or greater
- Total Testosterone – 6 to 86 ng/dl *many labs consider a
level above 50 to be elevated.
- Free Testosterone – .7 to 3.6 pg/ml
- Androstenedione – .7 to 3.1 ng/ml
Estrogen
levels - lower is better in this case. The lower the level
the more likely stimulation of an egg and development can be expected.
LH
levels - lower is also better in this case. An elevated
level of LH and a lower level of FSH could be a sign of PCOS and
additional tests should be ordered.
FSH
levels - lower levels of FSH signal a better ovarian reserve.
The LH and FSH levels should be close to a 1:1 ratio when PCOS testing
is being done and evaluated.
Prolactin
levels - when compared to the other female hormones, a
non-breastfeeding woman should have very low levels. If the level
of prolactin is raised, additional testing should be performed as
this hormone can interfere with ovulation.
TSH
levels - low levels as well as high levels can signal a
problem with thyroid function. If the levels are 'low normal' or
'high normal' additional thyroid testing should be ordered.
Progesterone
levels - levels below 10 do show ovulatory function, but
most doctor's prefer to see levels of 10 or higher. Levels below
5 may indicate a lack of ovulation.
Total
Testosterone levels - testosterone is a normal hormone
found in both the male and female, however, levels over 50 are considered
high by most doctors and indicate the need for additional testing.
Free
Testosterone levels - this is the level of testosterone
that is 'free' in the blood and not 'binded' to sex hormone binding
globulin (SHBG).
Androstenedione
levels - androgens are normally produced, but elevated
levels of androgens can interfere with normal egg development and
ovulation.
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