Excellent!

No, not the results here:

Babies conceived through IVF are much more likely to die at birth than those conceived naturally, the results of a new study show.

The death of babies is never to be considered excellent.

No, rather, we\’ve got a perfect example of two things: the state of science reporting and the much better state of science.

For there we\’ve got our headline, that IVF babies are more likely to die than those conceived naturally. Which isn\’t in fact what the article itself says at all.

Rather, the study looked at births conceived naturally, then those conceived naturally to women who also had one via IVF and then to those as a result of IVF from the same women.

Yes, IVF risks were higher than the first group: but much much lower than those in the third.

So, the result is that IVF, amongst those women who have had both that and conceived naturally, is much less risky than natural.

Her results also show that among women who conceived with fertility treatment but also had another child naturally, the spontaneously conceived baby was three times more likely to die than its IVF sibling.

"The adverse outcomes of assisted fertilisation that we noted compared with those in the general population could therefore be attributable to the factors leading to infertility, rather than to factors related to the reproductive technology," Dr Romundstad said.

So, zero points to the headline writer for getting the wrong end of the stick and many plus points to the researchers themselves for doing what all too few do. Looking at correlation and causation in a mature manner. Looking at babies conceived by IVF alone is never going to tell us all that much, for those created that way will of course be to people who already have problems with conception in some manner. ( We might also note that the 30% rise in risk isn\’t in fact all that large as the absolute risks are pretty low: 6 in a thousand is it? But the three times increase is indeed large.)

Spiralling off into pure speculation (as I am wont to do and as usual, on the basis of very little fact) what might explain that huge gap between natural and IVF in the same women? Well, umm, might it be the men? Some subset of IVF births are with donated eggs. Some subset are with the woman\’s own eggs but donated sperm and another with the couple\’s own of both.

OK, perhaps not the men in fact, but those natural conceptions will obviously be with the couple\’s own gametes….while a substantial portion of the IVF births will be with one or another (or both) sets donated. So the higher risk amongst the naturals comes from the very point that (some) IVF is designed to overcome. Gametes that just aren\’t up to scratch.

1 thought on “Excellent!”

  1. Actually Tim, the explanation is even simpler than you suggest.

    All other things being equal the first birth, natural or IVF, is the riskiest unless it gives rise to complications of a kind that will affect subsequent births – which I know from personal experience as my partner had problems delivering our first child which resulting in her having to have a classic ‘up and down’ C-section rather than the less invasive lateral one used when women elect to give birth by this method.

    As a result, when our second child was born, a natural birth was not an option due to the internal scarring caused during the first birth.

    The difference here is a matter of simple biology plus difference in clinical practice. The IVF only group is, I suspect, more likely to be made of first-timers than either of the other groups, increasing the population-based risk of problems, while the natural then IVF group are likely to receive a greater level of attention from clinicians during labour than the natural-only because they’ve had IVF and knowledge of this, and that the stakes are higher for such a individual, is likely to result in their receiving a more solicitous level of care.

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