Examination of fetuses after induced abortion for fetal abnormality—a follow-up study - Medeira - 2005 - Prenatal Diagnosis - Wiley Online Library
"In the North-Western Region we offer a service to examine fetuses aborted after the diagnosis of fetal abnormalities. Many obstetricians use this service. We examined 343 mid-trimester fetuses over the last 5 years: 215 following an abnormal scan and 128 abnormal amniotic fluid or villus findings. When necessary, investigations were performed. A post-mortem examination was always required. As a result of fetal investigation, the scan diagnosis was modified or refined in 91 cases (42·3 per cent). In three of these cases, no fetal abnormality was found. For the fetuses diagnosed as abnormal by amniocentesis or chorionic villus biopsy, in one (0·8 per cent) the pre-termination diagnosis was not confirmed. The results were similar to those of our previous 5-year study except (a) diagnosis of neural tube defects was rarely based on amniocentesis in the present study (2/62, 3·2 per cent) compared with the previous one (32/103, 31 per cent), and (b) renal abnormalities were more often diagnosed in the pre-termination scan in the present study. We conclude that the examination of aborted mid-trimester fetuses by dysmorphologists continues to improve diagnosis, allowing more accurate genetic counselling for the families."
Of special note is that of 215 babies identified as having some fetal abnormality by ultrasound ("scan"), three had no fetal abnormality (not sure if it's statistically significant, but 3/215=1.4% chance of aborting a healthy baby following u/s diagnosis of a problem, or a 1.4% false-positive rate); and of the 128 babies identified as abnormal either by amniocentesis or chorionic villi sampling (CVS) -- cells from the baby are captured from either the amniotic fluid or the placenta itself, at a risk of miscarriage, and sent for genetic testing -- one of the babies killed for being abnormal was actually normal. -- And this is supposed to be the most accurate testing possible, but that statistically works out to a 0.8% false positive rate!
Also troubling is that in nearly half (42.3%) of the cases identified by ultrasound/scan, the autopsy did not confirm the original diagnosis -- it was "modified or refined". If memory serves me correctly, there were a few cases in which the autopsy found that the fetal abnormalities were *worse* than the scan suggested (thus there may have been a baby identified by u/s as likely having Downs Syndrome, but at autopsy was confirmed to have a lethal genetic defect, so likely would have been stillborn or died soon after birth, had he not been killed), or they were accurately but incompletely identified by scan (e.g., the baby was identified as likely having Downs Syndrome, which was correct, but the u/s missed that he also had a cleft palate). However, in most cases, the "modifications or refinements" were more minor than the u/s suggested -- thus a baby identified as likely having Downs Syndrome did not actually have Downs, but merely had club foot -- still an abnormality, but not nearly as major a defect as the u/s appeared to show.
What is so sad about these cases is that the majority of the time, the parents likely would not have aborted, had they known the truth. [Not that any abortion for fetal defect is acceptable, but it's like knowing someone committed suicide because he thought he lost all his money in a stock market crash, only for his survivors to find out afterward that his investment advisor had pulled most of it out of the stock market and put it into a safe place. The death that was tragic in any event is also shown to be completely pointless.]