Aim: Maternal vitamin K (VK) deficiency can lead to fetal complications such as cerebral hemorrhage and bone malformations. In this study, we aimed to analyze changes in prothrombin time (PT) and protein induced by VK absence or antagonist II (PIVKA-II) in patients with severe hyperemesis gravidarum with suspected VK deficiency.
Methods: We compared 151 patients with severe hyperemesis gravidarum treated with intravenous nutrition to 46 patients undergoing cervical suturing or benign ovarian tumor surgery before mid-pregnancy.
Results: In the hyperemesis group, coagulation factors, including PT (s), prothrombin activity, INR, and APTT, showed a significant shift toward fibrinolysis compared to control (p < 0.001). The changes were within the normal range, except for PT (s), which was prolonged (14.6 ± 1.4 s). PIVKA-II was measured 25 times in 11 cases of hyperemesis and significantly correlated with PT (s). Moreover, VK was supplemented in four cases with severe VK deficiency, promptly normalizing both PT (s) and PIVKA-II.
Conclusions: Monitoring VK deficiency using PT (s) and PIVKA-II, with timely VK supplementation, may help prevent fetal complications in severe hyperemesis gravidarum.
Keywords: hyperemesis gravidarum; intracranial hemorrhage; protein induced by vitamin K absence or antagonist II; prothrombin time; vitamin K.
© 2025 Japan Society of Obstetrics and Gynecology.