Peter Moore: Why this medical technology is so vital

In the early 1970s I was shown an amazing piece of new medical technology.

It was developed from the technology used by the navy for detecting submarines. Sound waves were directed into the ocean, and the returning echo was analysed. We were told that it was called an ultrasound scan. Could this same technology be used in pregnant women to see the baby?

We were shown a picture of the scan while the expert pointed out the features. This was the baby’s head, and this was the back. Along with all the other students, I could not see anything. It just looked like a few black and white blobs. I continued to learn how to assess pregnancies in the old-fashioned way by feeling the woman’s abdomen and listening with a foetal stethoscope, which looks a bit like a plastic flower vase with a hole in the base.

By the late 1970s I was qualified and working in a maternity unit. Scans had improved, and I could make out now the baby, but it was still very unclear. It was not possible to take a photo and give it to the parents, although even if it were possible, they would have found it difficult to interpret. Where scans were very important was that we could now assess problems. If we thought the baby might be breech, we could now find out for certain and be prepared.

Another difficulty was assessing the duration of the pregnancy. Babies are full term forty weeks after the woman’s last period. If the baby is not born by forty-two weeks, the risks increase. But how do we know if the pregnancy has reached forty weeks? Some women’s periods are erratic. Perhaps she missed a period and became pregnant a month later.

If we induced labour early believing the pregnancy was forty-two weeks, we could be wrong and induce a premature baby. The best time to assess how far along a pregnancy was for a scan at twelve weeks, and so it was suggested that every woman should have a scan at twelve weeks. This sounded revolutionary. Would the parents accept this intervention, especially as the natural childbirth movement was gaining ground?

We need not have worried. It proved popular. As the technology improved, parents could see their unborn baby at twelve weeks. It was still not clear whether the baby was a boy or girl, although today we can have the same problem with teenagers. Occasionally we could say the baby was definitely a boy but never definitely a girl. Sometimes a penis could be seen on the scan, but if it was not seen, it could be a girl or the penis was not spotted.

We also ran into another problem. Some women refused a scan as a group of alternative practitioners started a false rumour that scans were dangerous and could damage an unborn child. Luckily this rumour disappeared, as it soon became clear that there was no evidence to suggest that scans were dangerous, and, anyway, parents loved having a scan and seeing their baby.

Today it is hard to see how maternity services could work without the ultrasound scan. Modern scans can detect a range of potential problems early by visualising the baby’s internal organs, the heart, blood flow and even cysts and tumours. The midwifery team can spot placenta praevia when the placenta is in front of the baby and arrange a caesarean section.

Parents are given a picture which is often included in their photobook “Baby’s first year”. Progress continues. In a modern 3D scan the baby’s features can be clearly made out. We now have 4D scans which include movement, the fourth dimension being time.

When I was shown these blurry black and white blobs fifty years ago, I did not realise that this technology would not only become routine but would also save many babies' lives.