This study was a multicenter retrospective cohort study of term nulliparous women who underwent labor, and was conducted to develop an automated machine learning model for prediction of emergent cesarean section (CS) before onset of labor. Nine machine learning methods of logistic regression, random forest, Support Vector Machine (SVM), gradient boosting, extreme gradient boosting (XGBoost), light gradient boosting machine (LGBM), k-nearest neighbors (KNN), Voting, and Stacking were applied and compared for prediction of emergent CS during active labor. External validation was performed using a nationwide multicenter dataset for Korean fetal growth. A total of 6549 term nulliparous women was included in the analysis, and the emergent CS rate was 16.1%. The C-statistics values for KNN, Voting, XGBoost, Stacking, gradient boosting, random forest, LGBM, logistic regression, and SVM were 0.6, 0.69, 0.64, 0.59, 0.66, 0.68, 0.68, 0.7, and 0.69, respectively. The logistic regression model showed the best predictive performance with an accuracy of 0.78. The machine learning model identified nine significant variables of maternal age, height, weight at pre-pregnancy, pregnancy-associated hypertension, gestational age, and fetal sonographic findings. The C-statistic value for the logistic regression machine learning model in the external validation set (1391 term nulliparous women) was 0.69, with an overall accuracy of 0.68, a specificity of 0.83, and a sensitivity of 0.41. Machine learning algorithms with clinical and sonographic parameters at near term could be useful tools to predict individual risk of emergent CS during active labor in nulliparous women.

Ahn TG, et al. J Korean Med Sci. 2024 Apr;39(13):e131. https://doi.org/10.3346/jkms.2024.39.e131

Aims: Altered redox state has been related to the development of normal pregnancy (NP) and preeclampsia (PE). Endothelial K _Ca 2.3 and K _Ca 3.1 (K _Ca s) play an important role in vasodilation, and K _Ca s levels are affected by oxidative stress. We investigated the mechanisms of oxidative stress-mediated K _Ca s expression modulation during NP and PE. Results: Human uterine microvascular endothelial cells were incubated in serum from normal nonpregnant women ( n = 13) and women with NP ( n = 24) or PE ( n = 15), or in vascular endothelial growth factor (VEGF), oxidized low-density lipoprotein (ox-LDL), progesterone, or estradiol-17β (E ₂ )-containing medium for 24 h. NP serum elevated H ₂ O ₂ levels via reducing catalase and glutathione peroxidase 1 levels, thereby enhancing K _Ca s levels via a H ₂ O ₂ /fyn/extracellular signal-regulated kinase (ERK)-mediated pathway. VEGF enhanced H ₂ O ₂ and K _Ca s levels and K _Ca 3.1 currents. K _Ca s were upregulated and K _Ca s activation-induced endothelium-dependent relaxation (EDR) was augmented in vessels from pregnant mice and rats. Whereas PE serum, ox-LDL, progesterone, or soluble fms-like tyrosine kinase 1 (sFlt-1) elevated superoxide levels via elevating NADPH oxidase 2 (NOX2) and NOX4 levels and reducing superoxide dismutase (SOD) 1 levels, thereby downregulating K _Ca s. sFlt-1 inhibited EDR. PE serum- or progesterone-induced alterations in levels of K _Ca s were reversed by polyethylene glycol-SOD, NOX inhibition, or E ₂ . Innovation and Conclusions: This is the first study of how endothelial K _Ca s levels are modulated during NP and PE. K _Ca s were upregulated by soluble serum factors such as VEGF via H ₂ O ₂ generation in NP, and were downregulated by serum factors such as progesterone and ox-LDL via superoxide generation in PE, which may contribute to hemodynamic adaptations in NP or to the development of PE.

Particulate matter 2.5 (PM_2.5) levels are associated with adverse pregnancy outcomes. In this retrospective cohort study, we examined whether the concentration of indoor PM_2.5 affected pregnancy outcomes. Additionally, we evaluated biomarkers of pregnancy-related complications caused by fine dust. We collected clinical information and data based on residential addresses from the Air Korea database to assess PM_2.5 exposure levels. As a multicenter prospective cohort study, we measured the indoor PM_2.5 concentration and inflammatory and oxidative stress markers. The PM_2.5 concentration of the low-birth-weight (LBW) delivery group was 27.21 μg/m³, which was significantly higher than that of the normal-birth-weight (NBW) group (26.23 μg/m³) (p = 0.02). When the newborns were divided by sex, the PM_2.5 concentration of the LBW group was 27.89 μg/m³ in male infants, which was significantly higher than that of the NBW group (26.26 μg/m³) (p = 0.01). In the prospective study, 8-hydroxy-2-deoxyguanosine significantly increased in the high-concentration group (113.55 ng/mL, compared with 92.20 ng/mL in the low-concentration group); in the high-concentration group, the rates of preterm birth (PTB) and small size for gestational age significantly increased (p < 0.01, p = 0.01). This study showed an association between PM_2.5, oxidative stress, and fetal growth, with the PTB group being more vulnerable.

The incidence of pelvic organ prolapse (POP) is increasing in our aging society. We aimed to evaluate the clinical usefulness of translabial ultrasound (TLUS) by comparing the findings of POP-Q examination and TLUS in advanced POP patients and we also aimed to evaluate the prevalence of rectocele and enterocele on the TLUS. We analyzed the TLUS and POP-Q exam findings of 363 symptomatic POP patients who visited our clinic from March 2019 to April 2021. We excluded three patients who had conditions mimicking POP, as revealed by the TLUS. The most common POP type was anterior compartment POP (68.61%), followed by apical compartment (38.61%) and posterior compartment (16.11%) POP. Agreement between the POP-Q exam and TLUS was tested using Cohen’s kappa (κ). p values < 0.05 were considered statistically significant. The incidence of rectocele or enterocele was only 1.67% (6/360) and there was no rectocele or enterocele in most patients (246/252, 96.63%) when the POP-Q exam revealed posterior compartment POP, suggesting that they only had posterior vaginal wall relaxation. The positive predictive value of the POP-Q exam for detecting rectocele or enterocele (as revealed by TLUS) was only 2.38%, whereas the negative predictive value was 100%. In conclusion, the application of TLUS is useful in the diagnosis of POP, especially for differentiation of true POP from conditions mimicking POP. The correlation between the POP-Q exam and TLUS is low, especially in posterior compartment POP, and therefore, patients with POP-Q exam findings suggesting posterior compartment POP should undergo TLUS to check for rectocele or enterocele. The use of TLUS in the diagnosis of POP patients can improve the accuracy of the diagnosis of POP patients in conjunction with a POP-Q exam.

Among the non-invasive screening methods for the identification of fetal aneuploidy, NIPT (non-invasive prenatal testing) shows the highest sensitivity and specificity in high-risk pregnancies. Due to the low false positive rate of NIPT, it is assumed that the implementation of NIPT as a primary screening method may reduce the number of invasive fetal tests and result in a similar or lowered cost in the overall detection of Down syndrome. However, most previous studies are based on theoretical economic analysis. This study aims to determine the cost effectiveness of various prenatal test strategies, including NIPT, in real clinical settings in both low risk and high risk pregnancies. In this prospective observational study, women (< 24 weeks) with singleton or twin pregnancies will be enrolled in 12 different healthcare institutions. The participants will be grouped based on the risks of fetal chromosomal abnormalities and will be counseled on the various screening or diagnostic methods, including NIPT, according to the aneuploidy risk. The final decision on screening or diagnostic methods will be made by patients after counseling. Questionnaires regarding factors affecting the decision on prenatal test will be answered by the participants and physicians. The economic analysis on final total costs will be compared according to the various prenatal test strategies. The results of present study are expected to have a significant impact on national policies in determining Korean prenatal screening test strategies and to help in developing novel and effective prenatal screening tests in the future.