Clinical significance for assessing adaptive hemostasis changes during multiple pregnancy after in vitro fertilization

   Aim: to assess adaptive hemostasis changes in multiple dichorionic pregnancy after in vitro fertilization (IVF).   Materials and Methods. A prospective observational randomized controlled trial was conducted by examining 58 and 46 pregnant women with multiple dichorionic diamniotic twins resulting from applying assisted reproductive technologies (ART) and spontaneous delivery (comparison group), respectively. Hemostasis parameters were studied as follows: activated partial thromboplastin time (APTT), prothrombin time (PT), thrombin time (TT), fibrinogen, antithrombin, protein C, protein S, functions of protein С (РrоС Global test), D-dimer, platelet aggregation with adenosine-5-diphosphate (ADP), ristocetin, and collagen.   Results. A high coagulation potential was revealed, more prominent after using ART (p < 0.05). Fibrinogen level gradually increased while gestation age increased, whereas APTT, PT and TT level decreased. In the group with natural conception, fibrinogen increased by 22 % in the second trimester, reaching 4.5 g/L (95 % CI = 4,2–4,8) and by 6 % in the third trimester, reaching 4.8 g/L (95 % CI = 4,3–5,4), whereas in the IVF group – by 26 %, reaching 5.3 g/L (95 % CI = 4,7–5,6) and by 21 %, reaching (6.5 g/L; 95 % CI = 5,2–6,8) in relevant trimester of pregnancy, respectively. Antithrombin level was lower in IVF patients – 76.8 % (95 % CI = 72.6 – 81.0) in the second trimester, reaching 70.6 % (95 % CI = 64.8–76.4) in the third trimester (p < 0.001). Protein C level did not differ significantly between groups and was low within the reference range. The aggregatogram demonstrated a high platelet hemostatic potential in IVF patients (p < 0.05) as early as in the first trimester: ADP-induced aggregation – 68.3 % (95 % CI = 62.9–73.7), ristocetin-induced aggregation – 53.1 % (95 % = CI 48.7–58.5), collagen-induced aggregation – 58.4 % (95 % CI = 52.1–64.7). In the third trimester, both platelet aggregation and functional activity (ADP-induced aggregation – 64.5 % [95 % CI = 59.3–69.7], ristocetin-induced aggregation – 68.4 % [95 % CI = 63.2–73.6], collagen-induced aggregation – 50.7 % [95 % CI = 44.3–57.1]; p < 0.05) and D-dimer level persistently increased, also more prominently in the IVF group (1.60 ± 0.46 ng/ml; p < 0.05).   Conclusion. Gestational adaptation in induced multiple pregnancies is at high risk of breach in compensatory mechanisms and requires monitoring for timely detection of decompensation signs and their correction to prolong pregnancy till optimal delivery time frame.