In a forthcoming meeting of the Society of Natural Cycle Assisted Reproduction (ISNAR) Professor Bob Edwards (who initiated the first in vitro fertilization (IVF) pregnancy of the famous baby Louise Brown in 1978) and other fertility experts are expected to call for a reduction in the use of hormones that stimulate ovaries to produce eggs.
A conference of fertility experts this month will call on the IVF industry to rethink its approach. They say hormones used to "kickstart" the ovaries could cause chromosomal damage to more than half of eggs, rendering them useless. The treatments may also affect the womb lining, preventing embryos from implanting.
These fertility experts think that for some women the net effect of using the ovulation stimulation drugs might be a net harm for their prospects of getting pregnant.
While fertility drugs like Clomid (which causes a false signal of low estrogen to cause gonadotropin hormone release) are used for many IVF procedures they are not always necessary. Professor Edwards used eggs naturally produced by the menstrual cycle to start the pregnancy that produced Louise Brown. Also, it is possible to use lower doses of fertility drugs and some of these experts think fertility doctors should lower their doses.
The case against the fertility drugs has not been proven. But these fertility researchers and practitioners think the case is strong enough to argue for changes in procedures used by fertility clinics.
Another fertility pioneer, Robert Winston, the peer, said: "The trend is to get as many eggs as possible, but that may be counterproductive. From the research we've done, the main risk is that doing this produces chromosomal damage in at least half, if not 70 per cent, of eggs. New studies are needed to prove the drugs are causing the damage, but it is my strong suspicion that this is the case."
What is needed is another way to produce eggs for women with aged ovaries. That is coming. Within 10 to 20 years time advances in technologies for stem cell manipulations will produce eggs suitable for fertilization with sperm. It will become possible to take adult cells and expose the cells to a series of chemicals and/or gene therapies to turn them into embyronic cells and then stimulate them to divide into eggs.
Cutting back on fertility drug usage might not reduce success rates. In fact, a couple of recent findings both point the way to much higher rates of success for IVF attempts. See my posts Biopsy Doubles Success Rate For IVF Babies and Embryo Tests More Than Double IVF Pregnancy Rate.
|Share |||Randall Parker, 2006 December 03 09:35 AM Biotech Reproduction|