-Tamoxifen when? Scope &
Indications of Tamoxifen as ovulogen:-:- In present day the main and
possibly the only indication of
prescribing TMX is when there are side effects with
CC particularly visual /neurological side effects . Scintillating Scotoma are the main contraindications of CC.
Though, in
such situation both the drugs (CC & TMX) are to be withheld forthwith
but one can use either agent at a lower dose after a gap
of 3-6 cycles couple of months..
Gonadotrophins are quite effective in
CC resistant cases but costly. CC has failed
after couple of cycles. Now, what are the practical options open to young women
in Indian perspective? Once counselling done after several cycles of failed CC,
many Indian couple (even uneducated couple) do realize that gonadotrophin is
badly needed for them but repent because they are simply unable to afford for G
cycle. Put in such a situation (after CC resistant cases) the option remaining
to the treating physician to prescribe TMX (as an alternative
to Gonadotrophin) and make some compromise. Doctor feel-“Watch- what happens”-.
Not to speak of Gonadotrophins : Many
Indians cannot afford further tests so
as to why CC resistance has followed: in her case--Unfortunately,
many Indian couple cannot afford for usual tests at this juncture - so as to why CC failed in their case. Such
tests, if not
carried out earlier are 1) AMH .2) AFC, 3) Insulin Resistance, 4) high D2 LH
& testosterone 5) DHEASO4, & 6) PRL --not to speak of other
costly tests. In such cases further tests so as to find the etiology of CC
resistant in particular women. We, Indian doctors have to make many compromises
at every step of clinical practice not only in the discipline of reproductive
medicine.
Like CC TMX is also an competitive
estrogen Antagonist –TMX ,like CC also competitively block the
estrogen binding sites at
the level
of arcuate nucleus of hypothalamus, and stimulate GnRH receptors located at Pit
for accentuated release of pit FSH & LH.
Is there any differential expression
of LH over FSH –particularly in CC failure cases? In fact there is about 3-4 fold rise of FSH
& LH while someone is on CC. But the differential expression FSH & LH
in the aforesaid two types of oral Ovulogens is still under study. I have a
feeling this part of CC /TMX have not been adequately explored. It is hoped by
many researcher that CC failure is due possibly to over expression of LH in
fair number women and is a major cause of CC failure à poor oocyte quality.
Those
who are biased for TMX they claim such disproportionate rise of LH on
cycle days 8-11 is not the case with TMX.
I
admit that I personally do not know about the differential expression of FSH
vs. LH in CC cycles against TMX cycles.
But many researcher believe that CC in fair no. of cases there is more
rise of LH during the cycle days of Day 8-Day 10àthereby interfering the
oocyte quality. Similarly in some cases of CC induced cycle serum E2 remain
at supraphysiological levels –explain partly the reasons of
failure of CC cycles. In such women one can use TMX as an iterative if the age
of the female partner is< 25 yrs or she cannot afford for gonadotrophin
cycle. Some also have claimed that LUF is more than TMX.
Miscarriages
rate and multiple preg rates are more or less same
with CC and Tamoxifen :- e.g. 10%
& ABOUT 22% RESPECTIVELY DEPENDING ON OTHER ASSOCIATED FACTORES LIKE Age of
female partner, BMI, ANDROGEN EXCESS DISORDERS, Hyperinsulinaemia, serum testosterone etc etc . But for the oral
Ovulogens to be effective the D2 serum E2 should be ideally> 50 pg/ml and
not less.
Additionally. Women
why are contraindicated for CC may also be a given few cycles of TMX RY after
due counselling. Such contraindications of CC are 1) impairment of hepatic
enzymes 2) [
Why oral Ovulogens in lieu of
gonadotrophins:- The advantages of CC/ Tamoxifen are low incidence of
multiple gestations, OHSS, low cost, minimal monitoring, .But we are all aware
of the fact that whatever agent we use in fair number of subfertile women
CC/TMX become resistant despite appropriate dosage e.g. Ov insufficiency, Hyperandrgenism, Insulin
resistance, Elderly women and women with BMI> 30 Kg/M2. In such
cases one prescribes oral ovulogens mostly CC but the doctor concerned is sceptical
right from the begging that CC/TMX may not work.
What to do in CC resistant cases? The causes are Treatment:
- one cans inj 50 mg of IM progesterone daily in late luteal phase to suppress
LH & FSH leels. But usually gonadotrophins are the usual protocol.
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