Prevalence of HBsAg in UK population

bidity or fetal or neonatal death was lower in the actively managed group, and one cannot help noticing, despite its statistical irrelevance, that one stillbirth occurred among the conservatively managed patients.To say induction oflabour is the less desirable treatment would depend on showing either that this leads to increased fetal damage and death or that any reduction in these end points was so small that women would accept them in preference to the psychological disadvantages and risk of caesarean section with active management.A randomised trial to show any decrease in mortality from say 3 to 1 per 1000 will require 18478 patients in each arm of the trial to have a 90% chance of showing a difference at the p<0 05 significance level.Such a trial would be difficult to organise but is the only way in which a meaningful conclusion to this long discussed problem may be reached.This, of course, is one of the greatest dilemmas of modem obstetrics.The risks which we are called on to balance are so low that only an enormous study will show the safest method of management.Even this evidence, however is not a perfect guide, as many patients might consider a small risk worth while for other perceived advantages.