Altered Haemostatic Values During Pregnancy in North–West Nigeria: Do Maternal Age and Parity Play Any Role?

Background: Normal pregnancy has been associated with alteration of the haemostatic system which has been linked to increased risk of thromboembolism. The study determined the haemostatic parameters in pregnant women in Kano, North-West Nigeria. Materials and Methods: One hundred and fifty pregnant women, aged 17-40 years and 100 age-matched nonpregnant women were enrolled for the study between August 2010 and October 2011 in Aminu Kano Teaching Hospital, Kano. Blood samples collected were analysed for prothrombin time (PT) and partial thromboplastin time with kaolin (PTTK) using Diagen reagents and platelet count using manual method while factors VII and VIII activities were determined according to manufacturers’ instructions of TECO kits and Cormay KG coagulometer. Results: There were significantly lower value of platelet count and higher value of factor VIII activity of (248.2 ± 78.8) X 109/L and 110.7 ± 46.6% in pregnant women compared to (289.4 ± 68.7) x 109/L and 96.8 ± 38.2% respectively, in non-pregnant women (P<0.05) while the values of PT, INR, PTTK and factor VII activity in pregnant and nonpregnant women showed no significant differences (P>0.05). Gestation period showed significant effects on PTTK and factor VII activity during pregnancy (P<0.05) but had no effects on platelet count, PT and factor VIII activity while insignificant increased values of factors VII and VIII activities, and increased parity were observed at the age-group 35-40 years. Conclusion: Changes in the haemostatic parameters in pregnancy are associated with reduced platelet count and increased factor VIII activity. Advanced maternal age, increased gestational age and parity may be risk factors for thrombosis. It is recommended that factors VII and VIII assays be included in routine antenatal tests.