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Most medical treatments of impaired fertility fall under the general
category of "ovulation induction" or "super-ovulation".
These terms imply that the goal is to either achieve ovulation in
women who do not ovulate, to improve ovulation in women who do not
ovulate well, or to acheive the development of multiple follicles
and eggs.
Most women who do not ovulate have polycystic ovaries, or a component
thereof. Treatment with glucophage is the first step in these women.
Glucophage may not entirely correct ovulatory function in and of
itself. In this case, additional treatment may be warranted.
Not all ovulations are the same. Ovulation should result in excellent
hormone production, including sustained production of progesterone.
But sometimes ovulation can occur and resulting hormone production
is less than optimal. Ovulation is a continuum, ranging from excellent
to a complete lack thereof. When ovulatory function begins to decline,
it is manifested by decreased progesterone production and shortening
of the luteal phase, or the second part of the cycle after ovulation.
The luteal phase must be twelve to fourteen days in length to allow
a conception time to implant. If the luteal phase is shorter than
this, fertilization may occur, but the embryo cannot successfully
implant because of the premature breakdown of the endometrium (lining
of the uterus). Luteal phase inadequacy is often manifested by spotting
for a couple or few days prior to the onset of the next menses.
Superovulation can be used to correct this problem.
And there are times when we simply want the ovaries to produce
more than the one egg that is typically matured each month. IVF
is the prime example of this. In an IVF cycle, we want the ovaries
to produce ten or so oocytes to improve the chances of success of
the IVF procedure.
A NEW APPROACH
For many years the time-honored and standard approach to ovulation
induction has been the use of clomiphene for four to six months
follwed by the use of gonadotropins for three or four months. If
all else failed, we would then discuss IVF. This approach has some
drawbacks. First of all, any month of treatment with ovulation induction
medications/hormones can be very frustrating. Secondly, although
not terribly expensive, the cost of cycle after cycle of ovualtion
induction does add up. Finally, this approach takes a long time
- up to a year and a half or more. It is not uncommon to develop
ovarian cysts with the use of ovulation induction agents, and this
postpones treatment for a month to allow the cysts to resolve. Particularly
with gonadotropins, treatment can only be pursued on an every other
month basis.
We believe there is a better approach. The use of combined Letrozole
and gonadotropins has become the new standard. Letrozole is used
for five days beginning on day 2 of the cycle, and after the Letrozole
is completed relatively low doses of gonadotropins are given for
three days. Ultrasound is then performed to evaluate the ovarian
response. HCG is given upon documentation of follicular maturity.
Progesterone is routinely used in the luteal phase for additional
support.
This approach has several advantages. The combined use of Letrozole
and gonadotropins seems to result in them working very synergistically
- relatively small doses of both result in excellent ovulation.
Progesterone production is excellent and sustained. Because small
doses are used, the cost is not prohibitive. The side effects are
minimal if any. And the chances of success with this are excellent.
Our data (unpublished) demonstrate that the pregnancy rates achieved
with three cycles of this combined approach are as good as those
achieved with four to six months of clomid followed by three or
four cycles of gonadotropins.
In brief, the cost is less, the number of cycles is significantly
reduced with pregnancy rates that are equivalent, and the length
of time spent pursuing ovulation induction/superovulation is dramatically
reduced. In our hands, this aproach has entirely replaced the prior
approach to ovulation induction.
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© 2005 Jarrett Fertility Group |