Material and Methods
Retrospective data analysisThe study population consisted of all consecutive cases of RhD negative pregnant women with request from the delivery ward for type-and-screen test, between October 2010 and October 2012 in the Stockholm region, Sweden. After this period, an RhD-negative test panel for type-and-screen requests in RhD negative women was introduced, in order not to cause delay when blood transfusions were needed. In the laboratory information system, the proportion of RhD negative women, with an RHD positive fetus, and a negative type-and-screen test at delivery was identified retrospectively, i.e. those where the anti-D prophylaxis administered in gestational week 28, at that time RhesonativĀ®, 1250 IU, (Octapharma, AG, Austria) was not detectable at delivery.