Many women worry that going through IVF
will deplete their ovarian reserve, as a result of which they will run out of
eggs, reduce their long-term fertility, and reach the menopause earlier.
Logically, this makes sense. We all know that women are born with a certain
number of eggs; and that their ovaries do not produce any new eggs after birth.
If the doctor stimulates the ovaries to grow lots of eggs during the IVF
treatment by giving hormonal injections, won’t this mean that there’ll be fewer
eggs left in the ovaries after the IVF treatment – especially if they are doing
many IVF cycles ? When going through IVF, the doctor harvests several eggs at
the time of egg retrieval by stimulating the ovaries with hormones (FSH or a
combination of FSH and LH). A woman with a menstrual cycle length of 28 days
ovulate only 12 eggs per year. But women going through IVF produce 15 or more
eggs at a time. Doesn’t this mean that IVF depletes the egg reserve faster than
usual and can lead to earlier menopause?
The ovaries are a pair of organs
situated in the pelvic region of women, one on each side. They act as the
reservoir for our eggs. Eggs are the cells which carry half of the information
(genetic blue print) necessary for creating a baby. Such precious egg cells are
stored, nourished and protected within specialized structures in ovaries called
follicles. A female fetus at around
18-22 weeks of gestation contains about 2,000, 000 follicles in its ovaries and
each follicle contains one egg. At the time of birth, a girl has only about
3,00,000 egg left in her ovaries – she’s lost over 80% of her eggs even before
being born.
The remaining follicles continue to get depleted during her life
time; and when there are only about 1000 follicles left, she reaches menopause.
A woman normally ovulate only about 400 eggs during her lifetime, releasing one
mature egg each month, from the time of attaining puberty until reaching
menopause. An ovary contains several immature follicles (and hence several
eggs!) but not all these follicles will become mature enough to release a
functional egg. More than 99.99 % of the follicles (and hence the eggs) are
simply lost, without serving their biological purpose. Human reproduction is remarkably inefficient.
During each menstrual cycle, several
ovarian follicles start growing in response to the FSH secreted by the
pituitary gland. Of these recruited follicles, only one follicle grows to
maturity, and this is called the dominant follicle. It carries the mature egg which will be
released during ovulation. The other follicles which fail to reach maturity are
lost . They die, and this natural process is called atresia. During IVF
treatment our body is supplied with high amounts of FSH (several folds higher
than our body naturally produces), in the form of injections. This high amount
of FSH helps to rescue more of the follicles which are recruited during that
particular menstrual cycle. This is the reason why IVF specialists are able to
harvest several eggs during an IVF treatment.
This is also the reason why IVF
treatment will not deplete your ovarian egg reserve. The follicles and the eggs
inside them which would normally have died during that particular menstrual
cycle are being rescued during an IVF cycle. This is why an IVF treatment will
not cause you to go through menopause earlier. This is true even if you do many
IVF cycles.
However, do remember that many infertile
women are at increased risk for having poor ovarian reserve and reaching menopause
early, whether they do IVF or not; this maybe because they have endometriosis,
or because they have undergone laparoscopic surgery. If they reach menopause earlier than expected
after having taken IVF treatment, they are quite naturally going to blame the
IVF treatment for this – whereas the reality is that they would have reached
the menopause early anyway, even if they had not done IVF.
Women who have undergone IVF treatment often fear that they will reach
menopause early. Now however, they can breathe a sigh of relief, for a new
study has said that IVF does not cause early menopause or even more severe
menopausal symptoms. One of the study dealing with the long-term effects of IVF
treatment, and was conducted by a team of researchers. The study involved
almost 200 women who were among the first to undergo IVF, which involved a far
heavier drugs regime.
It was discovered that their menopause started at the
same age as the national average, i.e. the average of just over 50. The belief
that IVF could bring on the menopause early is due to the fear that
ovary-stimulation for releasing the eggs required for treatment might bring
about their speedy decline.
Doctors have long been against this notion but
there wasn't any clinical evidence to prove the same. They found that the
participants' menopausal age was quite similar as that of their mother. Also,
there wasn't any increase in menopausal symptoms with the number of treatments,
even though their results were not compared with non-treated controls. It was
unknown territory in those days. Although all the studies showed that the
treatment was safe, it was ground-breaking and we couldn't predict the
potential long-term impacts.
Overall, follicle stimulation "appears to
have no lasting impact on the timing or symptoms of the menopause. Since many
of the women received multiple treatment cycles and large doses of drugs, the
current trend towards milder stimulation should have no effect either, which is
reassuring for the future. This is a question patients often ask - and it's
very useful to finally have point to which offers them reassurance that IVF
will not affect the timing or severity of the menopause."
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