On BioScience and Life and Such

Posts Tagged ‘stem cells’

What is an embryo if not cells with potential

In Uncategorized on August 22, 2008 at 10:05 am


post to news.thinkgene.com

Watch me dive head first into a can of worms

Embryonic stem cells are just that, – cells. They are life of course, but my belief is that the ethical discussion surrounding the use of them stems (sic) from……a potential for life. Specifically, a potential to lead to the live birth of a human being.

So what happens if we try and put numbers on that potential.

For fertilization and pregnancy the statistics are:

  • 33-43 % if the fertilization was a result of ART/IVF- wikipedia
  • 10-33 % after a single sexual intercourse – ref
  • ~90 % over a year for young women in a general population when having unprotected intercourse

    ..A sexually active teenager who does not use contraception has a 90% chance of becoming pregnant within a year… – Medline Plus

After fertilization, the chance (potential) for an embryo that has reached the blastocyst stage, of developing further is largely dependent on implantation:

A related issue that comes up in this debate is how often fertilization leads to an established, viable pregnancy. Current research suggests that fertilized embryos naturally fail to implant some 30% to 60% of the time. Of those that do implant, about 25% are miscarried by the sixth week LMP (after the woman’s Last Menstrual Period). As a result, even without the use of birth control, between 48% and 70% of zygotes never result in established pregnancies, much less birth. – from wikipedia

And finally, for giving birth to a child when pregnant (regardless of the health of the baby) the statistics are:

  • 85-90 % when pregnancy is clinically recognized – ref
  • 100 % 35-36 weeks post fertilization (premature birth) –wikipedia

From these numbers, would anyone suggest to ban contraception or advocate giving everyone access to free ART/IVF ? …. – No ?

But, if the potential for life is your dominant guiding light, you should. And also if you are arguing against the use of embryonic stem cells, be aware that you are arguing in favor of a chance potential of as low as 30 %.