ABSTRACT
Purpose: Feto-maternal haemorrhage (FMH) is a complication of pregnancy and large FMH may lead to life-threaten- ing anaemia in the fetus or newborn. In addition, exposure of Rhesus (Rh) D negative women to small amounts of fetal Rh D positive red cells during pregnancy or delivery may result in sensitization with its attendant problems of isoim-munisation. In most cases, the cause of FMH IS unknown. Through this study, we sought to determine if placental weight & diameter have any direct relationship with incidence and severity of FMH. Methods: This was a prospective study of parturients for presence of fetal red cells in the maternal blood circulation. The prepared slide was processed as in the acid elution test described by Kleihauer-Betke. The FMH was calculated using Mollison formula. Baseline data included maternal biodata, blood group, Rh D factor, placenta weight and diameter. Data generated were analysed with Frequency tables, cross-tabulations and Odd ratio and confidence intervals as appropriate. Results: Three hundred par-turients were studied. However, only two hundred and ninety-five parturients were analysed, with five excluded due to lysed blood samples. A total of 52 parturients (17.63%) had demonstrable FMH, of which 8 (2.71%) were large FMH (>15 ml foetal cells). Both the placenta weight (P < 0.005) and diameter (P < 0.042) were significantly associated with incidence of FMH, more with placenta weight than diameter. Incidence of demonstrable FMH was 24.12% (48/199) in the group with placenta weight greater than 500 g, in contrast to 4.17% (4/96) in the group with weight of placenta be-low or equal to 500 g. All the 8 parturients with large FMH had placenta weights greater than 500 g. Placenta diameters were greater than 22 cm in 41/197 (20.81%) who had demonstrable FMH, compared with 11/98 (11.23%) whose di-ameter was less than 22 cm. Conclusion: Both the placenta weight and diameter are significant predictors of FMH in parturients. However, placenta diameter appears to be a minor predictor. These are factors that can be assessed antena-tally by ultrasonography and in conjunction with other known obstetric factors, may possibly be considered in risk-based scoring system for predicting feto-maternal haemorrhage.