Medical Miracle, But Ethical Issues Prevail
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05 October 2010
Over more than three decades, the "test–tube baby" has been transformed from a man–made wonder into an almost medical routine, but one that still comes hedged with ethical questions.
It entails taking an egg from the woman, whose ovulation is stimulated by hormones, and fertilising it in the lab–dish with sperm from her husband or a donor.
The egg divides, is allowed to develop into an early–stage embryo in a nurturing fluid and is then inserted in the uterus. Doctors usually implant two or more embryos to boost the chances of a live birth.
"IVF is now a routinely established procedure," Martin Johnson, professor of reproductive sciences at the University of Cambridge, said.
Nearly four million children around the world have been born through IVF or a related technique, involving the transfer of a single sperm into the egg. Researchers have added a series of enhancements that have "fantastically improved" the chances of success, said Joelle Belaisch–Allart, head of the assisted reproduction unit at the Sevres Hospital, Paris.
They include improvements in stimulating eggs; screening egg and sperm for DNA health; better ways of handling the egg; and improvements in the fluid in which the embryo is cultured.
Like the contraceptive pill, IVF has had far–reaching social consequences. It has enabled career women the chance of extending their fertility way far beyond their 40th birthday and given single women the chance to be a mum, even if the child does not have a dad.
There have also been scandals that have sparked demands for tougher screening of IVF candidates and closer regulation of IVF clinics.
A controversy erupted over Carmen Bousada, a Spanish woman who was single and had twin boys at the age of 67 using IVF – and died from cancer last year, leaving infants just two and a half years old.
Last year, doctors were aghast at the case of "octomum," a 33–yearold Californian woman, Nadya Suleyman, who had octuplets in defiance of warnings that multiple pregnancies are closely linked to children born with abnormalities and developmental problems.
Suleyman , it turned out, was a single mother who already had had six other children aged seven and younger. On the clinical side, some studies have found a link between rare diseases and IVF, alT hough other experts say the picture is far from clear.
In the largest study to date, French researchers in June reviewed all assisted births in 33 registered clinics in France from 2003 to 2007, more than 15,000 children in all. They found a major congenital malformation in 4.24 percent, compared to two or three percent for the general population.
The main problems were heart disease and the uro–genital system, which was much more common in boys. "A malformation rate of this magnitude is a public health issue," said lead researcher Geraldine Viot, a clinical geneticist at thePort Royal maternity hospital in Paris.