Improving obstetric estimation of outcomes of extremely premature neonates: an evolving challenge.

AIMS A clinically useful website at the US National Institutes of Child Health and Human Development (NICHD) uses an algorithm based on a recent publication to estimate peri-viable neonatal outcomes. This algorithm uses gestational age, ultrasound estimated fetal weight (EFW), fetal sex, and the use of antenatal corticosteroids as the basis for estimation of outcomes and when used after birth is superior to such estimation by gestational age alone. Because one might be tempted to use this algorithm with obstetric patients, we tested its clinical applicability. METHODS We reviewed the literature using search terms relating to the above clinical factors. Next, we gathered data from the website. The range of outcomes for neonates was then estimated using the uncertainty derived for these clinical factors before birth from the literature review and the NICHD website algorithm. RESULTS We found increased uncertainty for estimating outcomes, as a function of the greater uncertainty in knowledge of the clinical factors in obstetrics as opposed to neonatology. CONCLUSIONS The imprecision during the time before birth seriously restricts the obstetric use of the NICHD algorithm at this time. Refining the precision of the algorithm prior to birth is necessary.