I did not know (though I suspected) that fertility clinics do not have the ability to implant an embryo. You are correct, of course, and this would explain why fertility clinics have such a relatively low success rate. An embryo left by itself, as fertility clinics apparently do, will likely not implant anyway.
Things like this bother me because it’s largely sophomoric and sensational reporting that borders on (if not crosses into) ignorance. I oppose abortion in all cases and will acknowledge that in very rare cases even the morning-after pill can be abortive. I stress very rare, as I have attempted to break this down in other topics in the past.
I just think this sort of pseudo-tabloid reporting does a disservice to the movement in general.
Actually, that's not true. For an embryo to be "left by itself" is exactly what nature does -- it's fertilized in the fallopian tube, and then is essentially dumped into the uterus, where it may or may not ever implant. IVF puts it in the same place, just via a different route.
The "relatively low" success rates of most fertility clinics are due to the fact that most of their patients are people who have been trying for a long time, both the natural way, and with non-invasive methods (e.g. just taking pills to promote ovulation), and have not been able to have a baby yet. Most of them have serious and/or complex problems impairing their fertility (sometimes involving a combination of male and female problems), and the science and technology haven't advanced yet to where these problems can be reliably overcome.
If you look at certain subsets of IVF patients/treatments, you'll see that the fertility clinics' success rates are right up there with nature's success rates (which are nowhere near as high as most people imagine). For women not beyond their early 30s, whose only "problem" is that they got their tubes tied (or blocked by a previous infection or tubal pregnancy), the overall success rate is virtually 100% -- usually takes 2-3 rounds of IVF to get a baby, but that's the same with natural conceptions. Most couples don't establish a viable pregnancy in the first month of actively "trying" the natural way, because the majority of naturally fertilized eggs don't progress all the way to the live birth stage -- most of the ones that don't either fail to implant or stop developing before the woman even knows she's pregnant. The IVF success rates are virtually identical for older women (even to age 50 and above) using donor eggs from younger donors. So IVF technology itself has reached a point where it's on a par with nature. But a majority of the patients doing IVF have little to no chance of having a baby the natural way, and thus statistically, IVF (even using their own eggs/sperm) provides a very significant boost in their success rates, despite the success rates being low in comparison to those of young healthy couples using either natural means or IVF.
Another interesting aspect is that some women have cycle irregularities that cause the implantation-receptive stage of the uterus to never coincide with the time when a naturally ovulated/fertilized egg will reach the uterus. This type of problem can be corrected by IUI or IVF (and sometimes by even less invasive methods). A narrower category of patients have what is known in Orthodox Jewish circles as "halachic infertility" -- i.e. they're only infertile due to following Orthodox Jewish law about the required delay between the end of the menstrual period and the resumption of sexual relations. If they'd have sex sooner after their period ends, they'd get pregnant the natural way, but they won't. There are some large Orthodox Jewish families out there whose children are entirely the result of IUI or IVF intervention to get around this problem (usually only IUI is needed). http://www.jewishwomenshealth.org/article.php?article=9 If you read through the gory details of the relevant Jewish law ( http://www.jewishwomenshealth.org/article.php?article=12 ), you'll marvel that Orthodox Judaism hasn't completely died out (and in fact, I strongly suspect that many individual lines DID die out on account of this, leaving few women in these communities who are naturally prone to cycle parameters that leave no intersection between following the mind-boggling law and capacity to reproduce).