As someone who has suffered a miscarriage in the past I find this article a little disturbing. It suggests that in a small number of cases some pregnancies are being terminated unnecessarily. Researchers have found that in the first six weeks of a pregnancy there is too much room for error in ultrasound scans. A small number of viable embryos at this stage may wrongly be thought to have miscarried when they are in fact still healthy. Whilst the scale of the problem is unknown a study suggests as many as 400 viable pregnancies could potentially be misclassified as a miscarriage. Currently two results are used to diagnose a miscarriage and thus the decision to terminate the pregnancy. These are that the embryo is greater than 6mm in length but without a heartbeat or that there is a pregnancy sac greater than 20mm but with no visible embryo. However, it is possible for this diagnosis to be incorrect as in the case studies in this article where the embryos were later found to be perfectly healthy. It seems, then, that the advice in the early stages of pregnancy is to err on the side of caution and request a second scan up to a week a later. An early scan can often be hard to read and not detect a heartbeat in a small embryo whereas a slightly later scan can sometimes give different results. Whilst miscarriages are still very common and as many as one is three pregnancies do end in a miscarriage it does seem as though these guidelines need to be reviewed if so many cases are misdiagnosed.