HEMATOLOGICAL AND BIOCHEMICAL PROFILE OF UNCOMPLICATED PREGNANCY IN NULLIPAROUS WOMEN - A LONGITUDINAL-STUDY

Background: Most laboratory parameters change during pregnancy. A seri al study of a large number of routine haematological and biochemical b lood parameters and biochemical urine parameters was conducted in a gr oup of 66 healthy nulliparous pregnant women, who had an uncomplicated pregnancy. Methods: Blood samples and 24-h urine samples were obtaine d at four weeks intervals during pregnancy and at 1 (1P) and 6 (6P) we eks after delivery. Results: During pregnancy, haemoglobin concentrati on, haematocrit and erythrocyte count were lower, mean cell volume was not different, and mean cell haemoglobin and mean cell haemoglobin co ncentration were enhanced. The platelet count during pregnancy was not different from the level at 6P but increased 60% at 1P. Serum ferriti n decreased 50% whereas plasma fibrinogen increased 100%. Serum creati nine (-28%), uric acid (-35%) and urea (-40%) concentrations were redu ced during pregnancy. The serum concentrations of sodium (-4 mmol/l) a nd potassium (-0.2 mmol/l) were lower, but serum chloride was unaltere d. Serum protein and albumen concentrations declined by 7.8 and 9.4 g/ l respectively. The serum concentrations of bilirubin, ALAT, ASAT and gamma-GT remained unaltered. Serum LDH was 30% above normal non-pregna nt values at 1P. The heat-stable alkaline phosphatase level increased in the third trimester. Heat-stable and heat-labile fractions were bot h elevated at 1P. The serum osmolality was 9 mosmol/kg lower and urine Volume was about 25% higher during pregnancy. The creatinine excretio n was unaltered but creatinine clearance increased by 25%. Conclusions : The concentrations of most components change during pregnancy. The i nterpretation of results of laboratory tests in pregnant women should be made with caution.