Protein C Activity in Women With Unexplained Infertility

Document Type : Original Articles


1 Department of Obstetrics and Gynecology, Faculty of Medicine, Ain Shams University, Cairo, Egypt.

2 Department of Obstetrics and Gynecology, Faculty of Medicine, Ain Shams University, Cairo, Egypt


Objectives: The relation between thrombophilia and infertility has drawn the attention in last few years. Most studies investigating the effect of inherited thrombophilia on infertility studied the relationship between thrombophilia and implantation failure. It was found to be a possible cause of impaired implantation in some subgroups of infertile women. Still thrombophilia screening in general infertile population is unjustified and in fact may lead to increased patient anxiety after a positive test result together with the increased cost. Due to the poor information available concerning the relationship between inherited thrombophilia and infertility, we performed a case–control study in order to evaluate the prevalence of protein C activity in women with unexplained infertility. Materials & Methods: This is a case–control study conducted to evaluate the prevalence of protein C activity in women with unexplained infertility conducted at Ain-Shams University Maternity Hospital. 48 women with unexplained primary infertility and another 48 fertile women of matched age group as their control were recruited from July 2011 to January 2013. Using the BIOPHEN Protein C 2.5 assay, protein C was measured following a specific activation with Protac, an enzyme extracted from snake venom. Activated protein C (APC) then specifically cleaves the specific substrate SaPC-21, releasing para-Nitroaniline (pNA), and its color is measured at 405 nm. 2(4.2%) cases of protein C deficiency were encountered in the unexplained infertility group while none found in the control group.Results: This study failed to find relationship between protein C activity and unexplained infertility compared to normal fertile population. In spite of finding 2 cases with protein C deficiency in the unexplained infertility sample population and none in the control group, this difference failed to reach significance (P=0.495 and P=0.076 respectively).Conclusion: In conclusion, this study failed to find any association between protein C activity and unexplained infertility. 


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