Objective: Since coronavirus disease 2019 (COVID-19) vaccination began, abnormal uterine bleeding (AUB) has occurred at a high rate. This study assessed the association between COVID-19 vaccination and AUB. Methods: In this retrospective cohort study, we analyzed mobile application data on menstrual cycles to investigate differences in the prevalence, duration, and amount of intermenstrual bleeding (IMB) after COVID-19 vaccination. We also analyzed the duration of menstruation, menstrual cycle length, and associated symptoms after the COVID-19 vaccination. Additionally, we investigated the prevalence of IMB according to the vaccine type. Results: After vaccination, IMB prevalence increased to 3.35% (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.46-1.76; p<0.0001) and IMB duration increased by 0.43 days (95% CI, 0.25-0.60; p<0.0001). The proportion of respondents whose amount of IMB was heavier than regular menstruation increased (OR, 2.96; 95% CI, 1.47-5.93; p=0.002). Menstrual duration decreased by -0.01 days (95% CI, -0.023 to 0.003; p=0.114), and menstrual cycle length increased by 1.39 days (95% CI, 1.30-1.48; p<0.0001). The proportion of participants who answered that there was a difference in menstruation amount increased (OR, 1.52; 95% CI, 1.41-1.64; p<0.0001). The prevalence of IMB increased regardless of the vaccine type. Conclusion There were statistically significant differences in the prevalence, duration and amount of IMB, menstrual duration, menstrual cycle length, and menstrual amount after COVID-19 vaccination. However, these values were not clinically meaningful and could be regarded as within the normal menstruation range.

Objective: Since coronavirus disease 2019 (COVID-19) vaccination began, abnormal uterine bleeding (AUB) has occurred at a high rate. This study assessed the association between COVID-19 vaccination and AUB. Methods: In this retrospective cohort study, we analyzed mobile application data on menstrual cycles to investigate differences in the prevalence, duration, and amount of intermenstrual bleeding (IMB) after COVID-19 vaccination. We also analyzed the duration of menstruation, menstrual cycle length, and associated symptoms after the COVID-19 vaccination. Additionally, we investigated the prevalence of IMB according to the vaccine type. Results: After vaccination, IMB prevalence increased to 3.35% (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.46-1.76; p<0.0001) and IMB duration increased by 0.43 days (95% CI, 0.25-0.60; p<0.0001). The proportion of respondents whose amount of IMB was heavier than regular menstruation increased (OR, 2.96; 95% CI, 1.47-5.93; p=0.002). Menstrual duration decreased by -0.01 days (95% CI, -0.023 to 0.003; p=0.114), and menstrual cycle length increased by 1.39 days (95% CI, 1.30-1.48; p<0.0001). The proportion of participants who answered that there was a difference in menstruation amount increased (OR, 1.52; 95% CI, 1.41-1.64; p<0.0001). The prevalence of IMB increased regardless of the vaccine type. Conclusion There were statistically significant differences in the prevalence, duration and amount of IMB, menstrual duration, menstrual cycle length, and menstrual amount after COVID-19 vaccination. However, these values were not clinically meaningful and could be regarded as within the normal menstruation range.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Objective: Since coronavirus disease 2019 (COVID-19) vaccination began, abnormal uterine bleeding (AUB) has occurred at a high rate. This study assessed the association between COVID-19 vaccination and AUB. Methods: In this retrospective cohort study, we analyzed mobile application data on menstrual cycles to investigate differences in the prevalence, duration, and amount of intermenstrual bleeding (IMB) after COVID-19 vaccination. We also analyzed the duration of menstruation, menstrual cycle length, and associated symptoms after the COVID-19 vaccination. Additionally, we investigated the prevalence of IMB according to the vaccine type. Results: After vaccination, IMB prevalence increased to 3.35% (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.46-1.76; p<0.0001) and IMB duration increased by 0.43 days (95% CI, 0.25-0.60; p<0.0001). The proportion of respondents whose amount of IMB was heavier than regular menstruation increased (OR, 2.96; 95% CI, 1.47-5.93; p=0.002). Menstrual duration decreased by -0.01 days (95% CI, -0.023 to 0.003; p=0.114), and menstrual cycle length increased by 1.39 days (95% CI, 1.30-1.48; p<0.0001). The proportion of participants who answered that there was a difference in menstruation amount increased (OR, 1.52; 95% CI, 1.41-1.64; p<0.0001). The prevalence of IMB increased regardless of the vaccine type. Conclusion There were statistically significant differences in the prevalence, duration and amount of IMB, menstrual duration, menstrual cycle length, and menstrual amount after COVID-19 vaccination. However, these values were not clinically meaningful and could be regarded as within the normal menstruation range.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Objective: Since coronavirus disease 2019 (COVID-19) vaccination began, abnormal uterine bleeding (AUB) has occurred at a high rate. This study assessed the association between COVID-19 vaccination and AUB. Methods: In this retrospective cohort study, we analyzed mobile application data on menstrual cycles to investigate differences in the prevalence, duration, and amount of intermenstrual bleeding (IMB) after COVID-19 vaccination. We also analyzed the duration of menstruation, menstrual cycle length, and associated symptoms after the COVID-19 vaccination. Additionally, we investigated the prevalence of IMB according to the vaccine type. Results: After vaccination, IMB prevalence increased to 3.35% (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.46-1.76; p<0.0001) and IMB duration increased by 0.43 days (95% CI, 0.25-0.60; p<0.0001). The proportion of respondents whose amount of IMB was heavier than regular menstruation increased (OR, 2.96; 95% CI, 1.47-5.93; p=0.002). Menstrual duration decreased by -0.01 days (95% CI, -0.023 to 0.003; p=0.114), and menstrual cycle length increased by 1.39 days (95% CI, 1.30-1.48; p<0.0001). The proportion of participants who answered that there was a difference in menstruation amount increased (OR, 1.52; 95% CI, 1.41-1.64; p<0.0001). The prevalence of IMB increased regardless of the vaccine type. Conclusion There were statistically significant differences in the prevalence, duration and amount of IMB, menstrual duration, menstrual cycle length, and menstrual amount after COVID-19 vaccination. However, these values were not clinically meaningful and could be regarded as within the normal menstruation range.

Background: Active surveillance (AS) has emerged as a viable management strategy for low-risk papillary thyroid microcarcinoma (PTMC), following pioneering trials at Kuma Hospital and the Cancer Institute Hospital in Japan. Numerous prospective cohort studies have since validated AS as a management option for low-risk PTMC, leading to its inclusion in thyroid cancer guidelines across various countries. From 2016 to 2020, the Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) enrolled 1,177 patients, providing comprehensive data on PTMC progression, sonographic predictors of progression, quality of life, surgical outcomes, and cost-effectiveness when comparing AS to immediate surgery. The second phase of MAeSTro (MAeSTro-EXP) expands AS to low-risk papillary thyroid carcinoma (PTC) tumors larger than 1 cm, driven by the hypothesis that overall risk assessment outweighs absolute tumor size in surgical decision-making. Methods: This protocol aims to address whether limiting AS to tumors smaller than 1 cm may result in unnecessary surgeries for low-risk PTCs detected during their rapid initial growth phase. By expanding the AS criteria to include tumors up to 1.5 cm, while simultaneously refining and standardizing the criteria for risk assessment and disease progression, we aim to minimize overtreatment and maintain rigorous monitoring to improve patient outcomes. Conclusion This study will contribute to optimizing AS guidelines and enhance our understanding of the natural course and appropriate management of low-risk PTCs. Additionally, MAeSTro-EXP involves a multinational collaboration between South Korea and Australia. This cross-country study aims to identify cultural and racial differences in the management of low-risk PTC, thereby enriching the global understanding of AS practices and their applicability across diverse populations.

Objective: Since coronavirus disease 2019 (COVID-19) vaccination began, abnormal uterine bleeding (AUB) has occurred at a high rate. This study assessed the association between COVID-19 vaccination and AUB. Methods: In this retrospective cohort study, we analyzed mobile application data on menstrual cycles to investigate differences in the prevalence, duration, and amount of intermenstrual bleeding (IMB) after COVID-19 vaccination. We also analyzed the duration of menstruation, menstrual cycle length, and associated symptoms after the COVID-19 vaccination. Additionally, we investigated the prevalence of IMB according to the vaccine type. Results: After vaccination, IMB prevalence increased to 3.35% (odds ratio [OR], 1.61; 95% confidence interval [CI], 1.46-1.76; p<0.0001) and IMB duration increased by 0.43 days (95% CI, 0.25-0.60; p<0.0001). The proportion of respondents whose amount of IMB was heavier than regular menstruation increased (OR, 2.96; 95% CI, 1.47-5.93; p=0.002). Menstrual duration decreased by -0.01 days (95% CI, -0.023 to 0.003; p=0.114), and menstrual cycle length increased by 1.39 days (95% CI, 1.30-1.48; p<0.0001). The proportion of participants who answered that there was a difference in menstruation amount increased (OR, 1.52; 95% CI, 1.41-1.64; p<0.0001). The prevalence of IMB increased regardless of the vaccine type. Conclusion There were statistically significant differences in the prevalence, duration and amount of IMB, menstrual duration, menstrual cycle length, and menstrual amount after COVID-19 vaccination. However, these values were not clinically meaningful and could be regarded as within the normal menstruation range.

Background/Aims: H2 receptor antagonists (H2RA) have been used to treat gastritis by inhibiting gastric acid. Proton pump inhibitors (PPIs) are more potent acid suppressants than H2RA.However, the efficacy and safety of low-dose PPI for treating gastritis remain unclear. The aim was to investigate the efficacy and safety of low-dose PPI for treating gastritis. Methods: A double-blind, noninferiority, multicenter, phase 3 clinical trial randomly assigned 476 patients with endoscopic erosive gastritis to a group using esomeprazole 10 mg (DW1903) daily and a group using famotidine 20 mg (DW1903R1) daily for 2 weeks. The full-analysis set included 319 patients (DW1903, n=159; DW1903R1, n=160) and the per-protocol set included 298 patients (DW1903, n=147; DW1903R1, n=151). The primary endpoint (erosion improvement rate) and secondary endpoint (erosion and edema cure rates, improvement rates of hemorrhage, erythema, and symptoms) were assessed after the treatment. Adverse events were compared. Results: According to the full-analysis set, the erosion improvement rates in the DW1903 and DW1903R1 groups were 59.8% and 58.8%, respectively. According to the per-protocol analysis, the erosion improvement rates in the DW1903 and DW1903R1 groups were 61.9% and 59.6%, respectively. Secondary endpoints were not significantly different between two groups except that the hemorrhagic improvement rate was higher in DW1903 with statistical tendency. The number of adverse events were not statistically different. Conclusions DW1903 of a low-dose PPI was not inferior to DW1903R1 of H2RA. Thus, lowdose PPI can be a novel option for treating gastritis (ClinicalTrials.gov Identifier: NCT05163756).