English

Abstract

BACKGROUND : Normal pregnancy is associated with substantial changes in the tissue factor pathway and in the wider haemostatic system (1) . It is also characterized by impressive changes in the activating and inhibitory pathways of coagulation and fibrinolysis resulting in an accelerated, but well balanced, process of thrombin formation and resolution. These changes serve to protect the mother from the hazard of bleeding imposed by placentation and delivery, but they also carry the risk of an exaggerated response, localized or generalized, to coagulant stimuli (2) . Hemorrhage occupies an important position in the etiology of maternal mortality and therefore, remains a major problem (3) . To what extent normal pregnancy affects coagulation is not well known in our locality. Thus, our study aims to find out the changes that occur in the coagulation parameters in pregnancy as compared to that in normal controls. METHODS : The study population included 25 healthy pregnant women, who visited the antenatal clinic of the KIMS Hospital in Narketpally, Nalgonda AP, between October 2008 and May 2009. 25 healthy age-matched non-pregnant women served as controls for the study. Both subjects and controls were randomly chosen from general population of pregnant women. Prothrombin Time test was done by using reagents bought from UNIPLASTIN, TULIP DIAGNOSTICS (P) LTD. When UNIPLASTIN reagent is added to normal citrated plasma, the clotting mechanism is initiated, forming a solid gel clot within a specified period of time. RESULTS : The results showed that the control group has a mean Prothrombin Time of 9.16 sec with SD of ±1.10 where as the test group showed a mean Prothrombin Time of 14.32 Sec and SD of ±1.91, P <0.001 by the chi-square test is significant. Whereas the International Normalized Ratio INR for control group was 1.26 Sec and SD of ±0.15 Sec and the test group had INR of 1.67 Sec and SD of ±0.26 Sec, the p value is <0.96 by chi-square test is insignificant. The odds ratio for Prothrombin Time was 1.73 which indicates that the Prothrombin Time was significantly decreased in the test group. CONCLUSION : The fact that Prothrombin time is decreased in normal pregnancy should be interpreted with caution, and that INR is the better indicator of the coagulation profile of the individual, therefore Prothrombin Time should always be read with INR ratio.