Hello again,
Long term studies are not usually carried out to see if there are side effects as such - these would normally be determined at the testing stage (which might be long term depending on the product!), so that is where the yellow card scheme comes in.
Long term studies should be carried out, considering that all testing stage studies for topical oestrogen were restricted to 12 months and the drugs (estradiol and estriol) were supposed to be used for the shortest time necessary to relieve symptoms, which unfortunately has not turned out to be the case for vaginal atrophy, widely recognised as a long term (if not lifetime) condition.
They would be carried out if appropriate to determine the long term efficacy or particularly safety of a treatment.
What does 'if appropriate' means?
In the case of Vagifem - I imagine it just is not cost-effective due to the extremely low risk of harms, due to the very low dose. The effect of systemic oestrogen on the uterus has been much studied and the dose dependent nature quantified. I don't have any of the studies to hand - but just to repeat suzysunday - these have been extensively examined by the medical researchers and professionals to come to their informed conclusion that endometrial hyperplasia and thereafter potentially cancer would be extremely rare and therefore not justifying adding a progestogen routinely nor regular endometrial scanning either.
Sorry, 'not cost-effective due to the extremely low risk of harms, due to the very low dose' is for short term use and it can't be extrapolated for long term use. Besides, many users are not following the dosage indicated in the leaflet and tweaking doses at their own risk in order to relieve symptoms.
The effect of systemic oestrogen on the uterus has been much studied and the dose dependent nature quantified.
Systemic and topical are quite different routes of administration and the levels of absorption are not comparable.
... these have been extensively examined by the medical researchers and professionals to come to their informed conclusion that endometrial hyperplasia and thereafter potentially cancer would be extremely rare and therefore not justifying adding a progestogen routinely nor regular endometrial scanning either.
Again, this 'informed conclusion' is based on observational data, there are no studies to corroborate this for long term use, only for short term use (12 months)
Susysunday,
As I have already said before, my questions are not intended to scare anyone, their sole purpose is to clarify what's in stake here, risk/benefit ratio. That said, I think it is very wise to follow the manufacturer instructions regarding dosage, just to be on the safe side.
Wishing you well.
Conolly X