A randomized prospective clinical study performed on a group of 74 pregnant women (43 presenting with severe preeclampsia) proved that urinary levels of 15-F_2t-isoprostane were significantly higher in preeclamptic patients relative to the control (3.05 vs. 2.00 ng/mg creatinine). Surprisingly enough, plasma levels of 25-hydroxyvitamin D₃ in both study groups were below the clinical reference range with no significant difference between the groups. In vitro study performed on isolated placental mitochondria and placental cell line showed that suicidal self-oxidation of cytochrome P450scc may lead to structural disintegration of heme, potentially contributing to enhancement of oxidative stress phenomena in the course of preeclampsia. As placental cytochrome P450scc pleiotropic activity is implicated in the metabolism of free radical mediated arachidonic acid derivatives as well as multiple Vitamin D₃ hydroxylations and progesterone synthesis, we propose that Vitamin D₃ might act as a competitive inhibitor of placental cytochrome P450scc preventing the production of lipid peroxides or excess progesterone synthesis, both of which may contribute to the etiopathogenesis of preeclampsia. The proposed molecular mechanism is in accord with the preliminary clinical observations on the surprisingly high efficacy of high-dose Vitamin D₃ supplementation in prevention and treatment of preeclampsia.

Pregnancy-induced hypertension (PIH), especially when complicated with pre-eclampsia (PE), could be a life-threatening complication of pregnancy. Pre-eclampsia is one of the leading causes of perinatal morbidity and mortality in women. Pre-eclampsia is mainly characterized by hypertension and kidney damage with proteinuria. Abnormal placentation and altered structure of the placental barrier are believed to participate in the pathogenesis of pregnancy-induced hypertension, leading to PE. In the current study, we aimed to analyze the immunohistochemical expression pattern of E-cadherin and p120, two markers of epithelial–mesenchymal transition, in placental samples derived from a group of 55 patients with pregnancy-induced hypertension, including pre-eclampsia and 37 healthy pregnant controls. The results were correlated with the presence of an obtained early uterine artery flow notching during diastole on Doppler ultrasound. We observed a higher frequency of discontinuous E-cadherin staining in the basement membrane of syncytiotrophoblast in patients with PIH/PE compared to controls (p < 0.001, Fisher’s exact test). Moreover, the loss of continuity of E-cadherin expression correlated with the presence of a bilateral early diastolic notch on Doppler ultrasound (p < 0.001, Fisher’s exact test) and the presence of proteinuria (p = 0.013, Fisher’s exact test). These findings suggest that E-cadherin contributes to the integrity of the placental barrier, and its loss could be an immunohistochemical marker of PE.

Background: Many vaccines are safe and recommended during pregnancy. Transmission of maternal antibodies produced in large quantities after vaccination protects the neonate in the first months of life, until the first vaccinations in infancy. In Poland, at the time of the study, influenza, pertussis, and COVID-19 vaccines were recommended during pregnancy. Methods: The authors performed a survey study in a group of 591 post-partum women. They were asked about the safety of pertussis, influenza and COVID-19 vaccines in pregnancy. Data regarding vaccination during pregnancy according to Polish recommendations in relation to the type of vaccine were also analysed. Results: Although 50% of patients reported that, in their opinion, the pertussis vaccine is safe and recommended during pregnancy, only 17% were vaccinated. Similar results authors obtained regarding the influenza vaccine (51% and 6%, respectively). The highest knowledge and compliance with recommendations correlation to the education level was observed in women with college and university education: 65% of them thought that pertussis vaccine is safe and recommended during pregnancy; 27% of them were vaccinated; 63% of them reported that they know that influenza vaccine is recommended during pregnancy and 9% were vaccinated. In a group with the lowest education, 14% reported that the pertussis vaccine is recommended as well as 24%-influenza vaccine. No patient in this group was vaccinated during pregnancy. Conclusions: Low compliance of pregnant women was confirmed in our study, and the desperate necessity of patients’ education regarding the safety of recommended vaccines is warranted. We showed that even patients who know that the vaccine is recommended do not receive vaccination, and the lower the education level, the lower the compliance.