1.1 BACKGROUND Pre-eclampsia is a multi-systemic disorder defined as hypertension with significant proteinuria occurring in the second half of pregnancy in a woman who was previously nonhypertensive and non-proteinuric. Its incidence ranges between 2% to 8% of all pregnancies worldwide and between 2% to 16.7% in Nigeria. Studies in the University of Port Harcourt Teaching Hospital (UPTH) only reported the incidence of eclampsia in the center as 1.6%, however, pre-eclampsia accounted for 3.8% of all antenatal admissions and 0.6% perinatal mortality in UPTH. Hematological profile is considered one of the factors affecting pregnancy and its outcome. Some studies showed significant alterations in the components of full blood count including platelets as well as clothing profile especially the fibrin degradation products inpre-eclamptics. Thrombocytopenia is defined as platelet count less than 150×109 /L. It is associated with substantial foeto-maternal morbidity and mortality and as much as 15% to 50% pre-eclamptics develop thrombocytopenia. It may be one of the earliest clinical manifestations of the disease and is said to often precede other sensitive laboratory manifestations of pre-eclampsia such as elevations of serum urate levels. Platelets may play a central role in its pathogenesis. There is a dearth of literature on the pregnancy outcome in pre-eclamptics with thrombocytopenia and other haematological abnormalities; hence, the measurement of the haematological indices and platelet count in pre-eclamptics may be of great prognostic value for the mother and the foetus. This study seeks to investigate the haematological indices in pre-eclamptics and the effect of thrombocytopenia on maternal and perinatal outcome in UPTH. Laboratory investigation of haematological indices is feasible and can be performed in UPTH. 1.2 OBJECTIVES The main objective of this study is to determine the influence of haematological indices on maternal and perinatal outcome in the University of Port Harcourt Teaching Hospital. 1.3 METHODOLOGY In this cross- sectional longitudinal study from 20th January 2015 to 14th September 2015, 63 pregnant women with pre-eclampsia who were between the gestational ages of 28 weeks and 41 weeks in the UPTH were studied. This study population consisted of a cross-section of pregnant women with sustained elevated blood pressure equal or greater than 140/90mmhg measured on at least two occasions four to six hours apart, and proteinuria of 1+ or more on dipstick on at least two occasions four or more hours apart. Their full blood count with fibrin degradation product (Ddimer) was assayed at delivery with the auto-analyser in the UPTH Haematology laboratory. A structured proforma was used to obtain socio-demographic information. Data collected was entered into a spread-sheet. Statistical analysis of results was carried out using SPSS 19.0 for windows statistical software. A p-value of less than 0.05 was considered statistically significant.