Geesh, as I said, that was only one study I read and the only one I have access to at the moment considering I returned the more comprehensive research I had to my midwives.
Sorry, so you didn't do a full literature search when coming to this conclusion? You had a folder of evidence that someone else gave you? I strongly recommend to you, since you are a student, that you don't fall into the trap of other people's selection bias. How do you know they didn't leave out any papers that they disagreed with the conclusions of?
Unfortunately, even scientists have an agenda. And scientists are just people, so will often not publish data that proves the status quo, because that's not going to get placed in a good journal and improve their CV.
The neonatal mortality rate was on the 15,000 women in the study, not the general UK. The study was also done in the US. The mortality rate was around 5% for both groups -- no difference -- not 4 in 1,000.
Those two statistics are completely unrelated; not least because infant mortality and neonatal mortality are different things.
I was quoting the 10.8 / 4 in 1000 numbers to prove that my assertion that, in the UK (which has has routine 20wk ultrasounds for a couple of decades), infant mortality has fallen between 1982 and 2012, likely due to a number of reasons of which improved antenatal screening is just one and of which the significance is undefined.
Anyway, while I look to see if I can find some of the other studies I read, do you have a link to any studies that show that the 20-week scan does improve outcomes? Anecdotal evidence doesn't work for this.
You're the one that's making an assertion that goes against what other people consider to be true, and so you're the one that has burden of proof. HOWEVER, because this piqued my interest and I'm insomnia ridden, I refer you to the 2008 NICE (National Institute of Clinical Excellence) Guidance for Antenatal screening for low-risk women in the UK. It was reviewed in 2014, and it's findings have been confirmed and it's advice will remain unchanged for now.
https://www.nice.org.uk/guidance/cg62/evidence
Pages 134-179 specifically look at the evidence for various types of ultrasound examinations in pregnancy, and determine from the evidence available whether or not any difference is seen, and from that whether it should be a routine part of the NHS's low-risk antenatal screening programme.
I'll leave you to read it (they list all the studies that they have looked at in order to come to the conclusions that they have), but of second trimeter screening their conclusion is clear:
"There is high-level evidence that routine, rather than selective, ultrasound in early pregnancy before 24 weeks enables better gestational age assessment, earlier detection of multiple pregnancies and improved detection of fetal anomalies with resulting higher rate of termination of affected pregnancies. There is no good-quality evidence on long-term outcomes for women and their children."
So, we're picking more fetal anomolies, and whilst there's no evidence of improved long-term outcome, there's also no evidence of worsened long-term outcome due to fetal exposure of ultrasound waves.
After that, the question just remains: do you want to find out about your baby's tetraolgy of Fallot at 20wks so that you can give birth in a tertiary centre with on-site neonatal cardiac services, or when they come out blue and not breathing at district hospital or at your home birth?
20wk ultrasounds prove that most low-risk pregnancies are low risk pregnancies. I'd rather not find out mine was one of the minority of high-risk pregnancies when it was too late to do anything about it.
