Evaluation of protein fractions in the serum as potential determinants of risk of the recurrent miscarriages

Background: According to the World Health Organization, recurrent miscarriage is defined as the loss of 3 or more consecutive early pregnancies, affecting 0.5% to 3% of pregnant women. According to clinical practice, it is recommended to perform a diagnostic investigation after two consecutive miscarriages in order to identify the reason for miscarriages. Despite numerous investigations, around 40–60% of recurrent pregnancy losses is still idiopathic. In the conducted research, the utility of the determination of serum protein fractions in the diagnosis of recurrent miscarriage was evaluated. Material and methods: The study group consisted of 20 women (aged 36.12 ± 3.53) with recurrent miscarriage of undetermined aetiology. The control group comprised 20 non-pregnant women (aged 35.7 ± 3.28) who had given birth to healthy children at least twice. Blood serum collected by venipuncture was examined. Serum protein fractions were separated by electrophoresis in the SDS PAGE buffer system using a Mini PROTEAN 3 cell device. BioRad SDS PAGE Molecular Weight Standards covering a mass range of 6.5–200 kDa were used as a reference. Results: Electrophoretic separation revealed 71 protein fractions of 10 to 240 kDa. It was observed that protein fractions with molecular weights of 27, 36, 53 and 172 kDa were present more frequently in serum from women in the control group. Protein fractions of 28, 132 and 188 kDa predominated among patients in the experimental group. This research has demonstrated that the number of 53 and 172 kDa protein fractions decreased with the number of miscarriages. Conclusions: It is suggested that individual protein fractions may increase the risk of a miscarriage.