Is grand multiparity an independent predictor of pregnancy risk? A retrospective observational study

The statistical analysis in my report shows that, once confounding factors are accounted for, grand multiparous women who labour spontaneously are twice as likely as their less parous counterparts to have a spontaneous vaginal birth, with no statistically greater risk of a postpartum haemorrhage requiring transfusion.1 The purpose of multivariate analysis is to remove, as far as possible, the influences of the confounding factors that de Costa’s appraisal relies on.

The recommendation from my study is not that grand multiparous women be ignored, but that, if labour occurs spontaneously at the end of an uncomplicated pregnancy, they be treated no differently to their less parous sisters in terms of venous cannulation and blood cross-matching. I am on record as strongly recommending sensible, routine oxytocin-based management of the third stage of labour in all pregnancies.2

In the end, the question is whether or not evidence wins out over an individual’s historically influenced clinical beliefs.