Tuesday, October 05, 2010

Technology and reproduction, now and in the future

This year's Nobel Prize in Physiology or Medicine went to Robert G. Edwards, the British scientist who developed the technology of in-vitro fertilization

Today nearly four million people have been born thanks to in vitro fertilization, which occurs when sperm is injected into an egg cell outside the body and the resulting embryo is implanted back into the womb. (Watch a video of how in vitro fertilization works.)

Edwards first envisioned IVF during the 1950s and went on to develop and hone the technique in the 1960s and '70s.

He achieved his first success on July 25, 1978, when Louise Edwards, the world's first "test-tube baby" was born in the United Kingdom. Louise is unrelated to the scientist.

"This is a wonderful achievement and a great testimony to Edwards's pioneering work in reproductive science," said Richard Kennedy, a fertility expert at University Hospital in Coventry, U.K., and secretary general of the International Federation of Fertility Societies.

"The development of IVF has enabled many millions of couples to have a child who might not otherwise have been able to," he said in a telephone interview.

[. . .]

More than 10 percent of couples worldwide are infertile. In the past medical help was limited, but today IVF therapy results in successful births for roughly one in five of every fertilized egg implanted.

The odds for a healthy couple conceiving naturally are about the same.

Reproductive medicine allows for the possibility of very significant changes on patterns of childbearing. Given the increasing tendency of people to postpone childbearing to later and later ages, for economic and other reasons, demand for the technology based on that factor alone (in societies well advanced in the demographic transition) is set to grow. Québec, for instance, has opted to pay for the first three rounds of IVF treatment. One clinic in Toronto--almost certainly not alone in the world--is promoting the idea that women who anticipate postponing parenthood until later in life should take care to have some of the ovas collected and frozen, for later fertilization and implementation. Other, more outré examples, from now and in the foreseeable future, can probably be imagined by my readers.

Anna Smajdor's article "State-funded IVF will make us rich… or will it?" makes the good point that expecting IVF to rejuvenate economies by producing more potential workers--justifying state expenditure on IVF--is, at best, a profoundly problematic idea, one that doesn't take into consideration the various economic, emotional, health, and other costs of reproductive technology. IVF, and other like treatments, developed in order to meet the needs of couples who wanted to have children at a time of their choosing. The effects of these many individual desires on demographic processes in the long run are doubtless many, but one prediction I do feel safe in making is that the timespan of a human generation will become significantly longer: between the existing postponement of births and the ability to facilitate births later in life, age-specific fertility in older cohorts can be expected to rise significantly at the expense of the younger ones.

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