To calculate the normal birth rate for England, BirthChoiceUK asked the Department of Health Statistics Division to provide us with the numbers of women who had both a spontaneous onset and spontaneous delivery, and the proportion of these women who had received some form of anaesthesia.
To find the numerator we first took the number of women who had a spontaneous onset and delivery and subtracted out all those women who had had any regional anaesthesia - epidural, spinal or a combination of the two. We also subtracted the very small number recorded as having a general anaesthetic.
To find the denominator, we had to look at the number of usable Hospital Episode Statistics (HES) records submitted by each hospital. There are effectively two sets of records, one relating to onset and one to delivery. Sometimes the number of usable onset records is different to the number of usable delivery records. To calculate the normal birth rate we divided the number of normal births by the minimum of these two. The logic behind this is that to calculate the number of normal births you need information from both sets of records, thus it is only possible when you have both.
The Department of Health put in a considerable amount of effort into cleaning the data and correcting coding errors. Nevertheless we thought it prudent to filter out those hospitals for which we thought the data suggested anomalies.
We therefore excluded those hospitals for which:-
Our thanks go to Lesz Lancucki and Mary Grinsted at Statistics Division 2B, the Department of Health who have helped us enormously in the preparation of these figures.
Click the "back" button on your browser to return to the previous page.