Serial Changes in Plasma Fibrinogen Concentration and Fibrinolytic Activity in African Women on Oral Contraceptive Pills
Abstract
Several retrospective epidemiological studies suggest that there is an association between the use of oral contraceptive pills and increased risk of intravascular thrombosis. The present study reports on several changes in fibrinogen concentration and fibrinolytic activity after prolonged use of oral contraceptives in African women. Fibrinolytic activity by euglobulin lysis time (ELT) and plasma fibrinogen concentration (PFC) by clot weighing method were assessed among 20 African women who were new users of combined oral contraceptives (OCP). They were tested at pre-treatment and serially at six monthly intervals over a three year period. There was consistently a significant increase in fibrinogen levels (p < 0.001) and euglobulin lysis time (p < 0.00 1) with increasing duration of use of oral contraceptive pills. There was a positive correlation between the mean fibrinogen levels and ELT (r = O.89,p <0.01), and a negative correlation between fibrinogen and plasminogen activator content of fibrinolytic system (r = -0.84,p < 0.01). The mean fibrinogen values during OCP use were substantially higher than at pre-treatment. We conclude that although African women may have a low predisposition to thrombosis, their risk of having fibrin defect is increased after prolonged use of oral contraceptive pills. We suggest a clinical epidemiological study to provide a better understanding of the haemostatic changes observed in African women. (AfrJReprod Health 1997;1(2): 90—95)
KEY WORDS: Plasma fibrinogen,fibrinolytic activity, African women, contraceptivesFull Text:
PDFReferences
Meade TW, Brozovic M, Chakrabarti R, et al. Epidemiological study of the haemostatic and other effects of oral contraceptives. Brit I Haernatol 1976;34:353—64.
Prasad RNV, Ratnam SS. The cardiovascular and thromboembolic risks of oral contraception: a review. SingJ Obstet Gynecol 1980; 11(1 ):7—19.
Ratnam, SS, Prasad RNV. Current research into oral contraception in Singapore. Sing I Obstet Gynecol 1984;15:152—9.
Poller L, Thompson JM. Clotting factors during oral contraception. Brit Med 1 1 960;2:23—5.
Bonnar J, Sabra AM. Oral contraceptives and blood coagulation. I Reprod Med 1 986;3 1 (suppl 6) :551—6.
Laehnit-Fixon. Triphasic pill “neutral” effects on lipid profile. XI World Congress of Fertility and Sterility Newsletter. Germany: Schering A.G. Publishers, 1983;4:4—6.
Prasad RNV, Kon S, Ratnam SS. Effects of three types of combined contraceptives pills on blood coagulation, fibrinolysis and platelet function. Contraception 1993;38(4):369—83.
Wong V, Chan V, Tso SC, et al. The effects of oral contraceptives on coagulation and fibrinolytic parameters in the Chinese—a prospective study. Thromb Haernostas 1982;48:263—6.
Vessey MP, Doll R. Investigation of relation between oral contraceptive pills and thrombotic disease: a further report. BritMedJ 1969;2:651-7.
Poller L. Oral contraception, blood coagulation and platelets. In: Poller J, ed. Recent advances in thrombosis. Edinburgh and London: Churchill Livingstone Publications, 1973:181.
Dugdale M, Masi AT. Hormonal contraception and thromboembolic disease effects of the oral contraceptives on haemostatic mechanisms: a review of the literature. I Chronic Dis 1 975;23:775—80.
Famodu AA, Ehigiegba AE, Fakoya TA, Adeyi J, Diejomaoh FME. Effects of oral contraceptives on fibrinogen levels in African women. Haematologia 1991;243:135—8.
Famodu AA, Elom EU, Ehigiegba AE, Fakoya TA. Abnormal fibrinolytic activity in African women taking oral contraceptives. Blood Coag Fibrinol 1 993;4:64 1—2.
Famodu AA, Erhunmwunse RU, Elom EU. Fibrinolytic activity in women on oral contraceptive pills: variation due to haemoglobin genotype. Acta Tropical 1992;52:135—8.
Samsieo G. Comparative effect of OC combinations 0.15mg desogestrel + 0.03mg ethinyl oestracliol and 0.15mg levonorgestrel + 0.03mg ethinyl oestradiol on lipid and lipoprotein metabolism in healthy female volunteers. Contraception 1982;25(5):487—503.
Ingram GIC. A suggested schedule for the rapid investigation of acute haemostatic failure. I Clin Path 1960;14:356—60.
vonKaullaKM.Chemistryofthrombolysis:human fibrinolytic enzyme. Springfield, Illinois: Thomas, 1963:46—60.
Marsh NA. Measurement of fIbrinolytic capacity by the euglobulin lysis time method—a prob1cm of “units.” Thromb Res 1978; 12:197—200.
Meade TW, Chakrabarti R, Haines AP, North ERS, Stirling Y. Characteristics affecting fibrinolytic activity and plasma fibrinogen concentration. Brit MedJ 1979; 1:153—6.
Meade TW, North WRS, Chakrabarti R, et al. Haemostatic functions and cardiovascular death: early results of a prospective study. Lancet 1980;1:1050—1.
Lee AJ, Smith WCS, Lowe GDO, Tunstll-pedoe H. Plasma fibrinogen and coronary risk factors: the Scottish heart health study. I Clin Epidemid 1 990;43:9 13—9.
Refbacks
- There are currently no refbacks.