Namra Mahmood


Background: Protein C inhibitor (PCI) is a serine protease inhibitor synthesized by the liver. Apart from its function of inhibiting activated protein C (APC), PCI also inhibits activated factor II, thrombin thrombomodulin complex, factor XIa, tissue plasminogen activator (t-PA) and urokinase plasminogen activator (u-PA). Increased level of PCI has been found in patients with thrombosis and women using oral contraceptives. The aim of the present study is to observe the effect of combined oral contraceptive pills on PCI levels after three months of its use and mean change from baseline.

Materials & Methods: Cross sectional descriptive study carried out at the pathology department, post graduate medical institute (PGMI) between 01/03/2018 to 02/03/2019 after taking ethical approval. Purposive convenience sampling technique was used. Blood sample of the study population was taken before the start of medication and after three menstrual cycles. Protein C inhibitor levels and demographic data was collected and analyzed using SPSS.

Results: Among total 54 females, the age of the women ranged from 22 years to 44 years with a mean of 29.5 ±5.3 years. The parity of the women ranged from 1 to 6 with a mean of 3.06 ±1.20. The baseline value of protein C inhibitor levels ranged from 1.1 to 8.7 mg/l with a mean of 5.84 ± 1.83 mg/l at baseline and increased upon 3-months follow-up to 8.2 to 20.1 mg/l with a mean of 12.74 ±3.29 mg/l. The women aged 29-35 years had highest of PCI levels at follow up with a mean of 13.47 ±4.28 mg/l and primiparas had highest increase among groups and it was statistically significant (p-value < 0.001).

Conclusion: It can be concluded from the study that use of the second generation oral contraceptive for 3 months is associated with induction of prothrombotic state by increase in the level of protein C inhibitor in the absence of any other prothrombotic conditions.


Activated Protein C inhibitor; Protein C inhibitor; Thrombosis; Deep vein thrombosis; Oral contraceptives; Contraceptive agents.

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