Discovering the Holy Grail in postpartum uterine involution.

A Swiss study attempted to establish normal values for the uterine involution expected during the first 5 days postpartum. Two methods were used, apparently independently and without validation. One, named the finger method, consisted of estimating the height of the uterine fundus in finger breadths above or below the umbilicus. The other, the tape method, consisted of marking the distance between the uterine fundus and the pubic symphysis on a blank tape, which was subsequently read in centimeters against a measuring tape. The authors contend that normal uterine involution postpartum is governed by different factors according to whether it is measured by fingers or by tape. Thus, gestational age affected uterine involution when measured with fingers, but not when measured with a tape, whereas maternal age did the reverse. Apart from being based on a study population that defies any criteria of normality, a comparison of the results from finger and tape methods shows data that are incompatible with the anatomy of human fingers and the uterus postpartum. Yet, the authors suggest that these data should be used to differentiate electronically between normal and abnormal uterine involution, without considering what the consequences of such nonvalidated programming might be.