Friday, 11 October 2013

Does going through IVF causes premature menopause?

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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