HAEMATOLOGICAL INDICES AND THE EFFECT OF THROMBOCYTOPENIA ON MATERNAL AND PERINATAL OUTCOME IN WOMEN WITH PRE-ECLAMPSIA IN PORT HARCOURT NIGERIA

Abstract

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 non-
hypertensive 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 (D-dimer) 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.
1.4 RESULTS
The mean haemogram for the study population was 11.70±1.7. The mean haemogram for
severe and mild pre-eclampsia was 11.95±1.74g/dl and 11.39±1.69g/dl, respectively p=0.21.
Haemogram values did not predict the severity of pre-eclampsia or mode of delivery in this
study. The mean haemogram for pre-eclamptics with or without complications was
11.64±1.74g/dl and 12.34±1.57g/dl respectively. Hence haemogram values in this study
therefore did not influence presence or absence complications amongst the pre-eclamptics
studied. Mean haemogram for subjects who had worsening proteinuria was 12.33±1.08, while
that for those without worsening proteinuria was 11.38±1.62 (p-value=0.04), suggesting that
those subjects with worsening proteinuria had higher intrapartum haemogram than those without.
Bivariate analysis showed that haemogram with postpartum haemorrhage were significantly
associated (r=-0.278, p=0.027), even after controlling for estimated blood loss (r=-0.407,
p=0.001), suggesting that postpartum haemorrhage is likely to occur with decreasing
haemogram. The haemogram concentration in this study also did not influence other foeto
maternal complications like worsening hypertension, acute kidney injury, pulmonary oedema,
maternal mortality, abruptio-placenta, foetal distress, intra-uterine foetal death, birth asphyxia,
prematurity and admission into neonatal intensive care unit (Special Care Baby Unit).
The mean white blood cell count for subjects who developed foeto-maternal complications
versus those who did not was 8.47±4.11×109/l versus 5.88±3.148×109/l, p=0.18, suggesting that
white blood cell count did not predict disease severity or occurrence of foeto-maternal
complications in this study. In like manner, mean white blood cell count for subjects who had
vaginal delivery versus caesarean section was 8.32±3.84×109/l versus 8.23±4.25×109/l, p=0.94.
The bivariate correlation between white blood cell count and foeto- maternal clinical
characteristic was statistically significant for foetal distress (r=0.35,p=0.005) and foetal birth
asphyxia (r=0.39, p=0.002), respectively but it was not so for other foeto- maternal
complications.
The mean platelet count for the study population was 191.70±19.59×109/l. None of the
subjects in this study had thrombocytopaenia (<150×109/l), hence the effect of
thrombocytopaenia on maternal and foetal outcome in pre-eclamptics at delivery could not be
ascertained. Also, the mean platelet count for the subjects with severe versus mild pre-eclampsia
was 191.57±19.98×109/l and 191.86±19.46×109/l respectively, p=0.95. Similarly, the mean
platelet count for subjects who developed foeto-maternal complications versus those who did not
was 181.80±16.14×109/l versus 192.50±19.74×109/l, p=0.24, suggesting that mean platelet count
did not predict disease severity or occurrence of foeto-maternal complications in this study.
The mean D-Dimer amongst this study population was 1256.03±304.61ng/dl. D-Dimer did
not influence severity of disease, occurrence of complications and mode of delivery: the mean D
Dimer for mild and severe pre-eclampsia was 1191.43±319.19ng/dl and 1307.71±286.54,
p=0.13; mean D-Dimer level for subjects with foeto-maternal complications and those without
complications was 1253.19±307.53ng/dl and 1289.0±298.29ng/dl, respectively, p=0.24; the
mean D-Dimer for subjects who had vaginal delivery versus those who had caesarean was
1312±289.65ng/dl versus 1227.98±289.65ng/dl, p=0.31.

1.5 CONCLUSION
In this study, postpartum haemorrhage had an inverse relationship with haemogram
concentration suggesting that postpartum haemorrhage is likely to occur with decreasing
haemogram values. Haemogram concentration also had a direct relationship with worsening
proteinuria but did not influence other foeto-maternal complications. The haemogram values also
did not predict the severity of pre-eclampsia, mode of delivery or presence or absence of
complications amongst the pre-eclamptics studied, in a statistically significant manner
The white blood cell counts, in the subjects, were closely related to foetal distress as well
as foetal birth asphyxia in a statistically significant manner, but did not predict other aspects of
foeto-maternal outcome. None of the subjects in this study had thrombocytopaenia (<150×109/l)
and platelet counts did not correlate with foeto-maternal outcome in this study. The D-Dimer
values did not influence the severity of disease, occurrence of complications and mode of
delivery in this study.

HAEMATOLOGICAL INDICES AND THE EFFECT OF THROMBOCYTOPENIA ON MATERNAL AND PERINATAL OUTCOME IN WOMEN WITH PRE-ECLAMPSIA IN PORT HARCOURT NIGERIA