Factors contributing to APC-resistance in women with recurrent spontaneous miscarriages: Indian perspective

Phenotypic resistance to APC is a complex mechanism associated with increased risk of venous thrombosis in women with recurrent spontaneous abortions. The primary aim of this prospective case control study was to find out the frequencies of different congenital and acquired thrombophilic factors predisposing to APC resistance and to evaluate the strength of their association with recurrent pregnancy losses. FV Leiden accounted for around 40% of all APCR positive patients and the difference in the group frequencies compared with controls, was found to be statistically significant (p=0.001). 18.33% (11/60) FV Leiden-negative APC-resistant patients had

c values exceeding 95th percentile of the control population (145IU/dL), as compared to 3% in the control group (p=0.001). Mean FVIII level in control subjects was 118±14.0IUdL(-), compared with 127.7±31.2IUdL(-) in the patient group (p=0.009). Apart from FVIII, only the anti-phospholipid antibodies showed a statistically significant association with APCR phenotype (p=0.028), unlike other thrombophilic factors such as Protein C, Protein S, FV levels, HR2 haplotype or other rarer FV variants. The strong positive association of FVL mutation, anti-phospholipid antibodies and elevated FVIII levels with APCR phenotype calls for incorporating them as first line investigations in patients with recurrent spontaneous miscarriages with APCR positivity.