The most recent study on prenatal testing in the United States estimates that almost 75% of all pregnancies undergo prenatal screening for Down syndrome. This is an increase from just 25% in the 1980’s and 50% in the 1990’s. This increase in the number of women having prenatal testing for Down syndrome means two opposing decisions are being made more than ever: to abort or to continue a pregnancy positive for Down syndrome.
More selective abortions for Down syndrome than ever
The traditionally quoted 90% termination rate dates back to studies that were done in the late 1980’s. At that time, professional obstetric and genetic practice guidelines recommended that only women 35 years or older be offered prenatal testing. Given that pregnancies to women of that age or older, at that time, represented a significant minority, then it’s not surprising that only 25% of all pregnancies had prenatal screening for Down syndrome in the 1980’s.
Applying those two percentages provides an estimate of how many selective abortions occurred in any given year when the termination rate was 90%.
According to the study by Egan et al., represented in the graph above, there were around 5,000 pregnancies carrying a child with Down syndrome in 1988. With 25% of all pregnancies undergoing prenatal screening, then 1,250 of the Down syndrome pregnancies underwent prenatal screening. If every one of those mothers who received a screen positive went on to have diagnostic testing and 90% terminated after a diagnosis, then that would mean there were 1,125 selective abortions out of 5,000 total pregnancies.
Now, fast forward to present day, when almost 75% of pregnancies undergo prenatal screening for Down syndrome and the termination rate is estimated to be 75%. According to Egan et al., there are about 8,000 Down syndrome pregnancies each year now. With the estimated screen rate of 72%, then, 5,760 of those Down syndrome pregnancies would undergo prenatal screening. And, if each screen positive had diagnostic testing, a 75% termination rate means 4,320 of those pregnancies were aborted.
So, you see, a lower termination rate of 75% versus 90% actually results in 3,195 more abortions–a 380% increase in the number of selective abortions due to the increase in the number of women undergoing prenatal screening.
But it also means something else.
More women than ever are choosing to have a child with Down syndrome
The focus of columns and arguments about prenatal testing for Down syndrome tends to be on the high number of abortions following prenatal testing. Doing so misses another key decision that women are making: continuing pregnancies positive for Down syndrome.
Using the same numbers as above, consider that in 1980’s there were 1,125 abortions out of a total of 5,000 Down syndrome pregnancies in any given year. Of those 5,000, 1,250 had prenatal screening. So, 125 mothers chose to continue their pregnancies that they had learned prenatally might be positive for Down syndrome.
Again, fast forward to present day, where almost 75% of all pregnancies have prenatal screening for Down syndrome. While 75% of those that are diagnosed with Down syndrome terminate, that means 25% will decide to continue. Working with the same figures above, of the 5,760 pregnancies carrying a child with Down syndrome each year that received a screen positive result, 25% of those chose to continue their pregnancy. That means 1,440 moms chose to continue their pregnancies. Compared to the 125 who made that same decision in a given year in the 1980’s, that means 1,315 more women that chose to continue after a prenatal test result for Down syndrome–a 1,150% increase in the number of mothers choosing to continue their pregnancies positive for Down syndrome.
More support needed than ever
What this all really means, though, is that there are more moms than ever receiving news prenatally that they did not expect, that they do not understand completely, and that need support and care while they make their decision. And, of those moms now undergoing prenatal testing, while more are choosing to terminate than ever before, so, too, are there more moms than ever choosing to have a child with Down syndrome.