Risk factors for pregnancy-associated heart failure with preserved ejection fraction and adverse pregnancy outcomes: a cross-sectional study.

BACKGROUND: Although pregnancy-associated heart failure with preserved ejection fraction (HFpEF) is increasing and contributing to maternal morbidity, little is known about its impact on pregnancy. We examined the risk factors for and adverse pregnancy outcomes of HFpEF in pregnant women. METHODS: We conducted a cross-sectional analysis of pregnancy-related hospitalizations from 2009 to 2020 using the perinatal database of seven multicenters. Cases of HFpEF were identified using the International Classification of Diseases and echocardiography findings. The patients were categorized into the HFpEF and control groups. Risk factors were evaluated using multivariate logistic regression analysis to generate odds ratios (OR) and 95% confidence intervals (CI). Furthermore, adjusted associations between HFpEF and adverse pregnancy outcomes were determined. Risk scores for the stratification of women at a high risk of HFpEF were calculated using a statistical scoring model. RESULTS: Of the 34,392 women identified, 258 (0.76%) were included in the HFpEF group. In multivariate analysis, HFpEF was significantly associated with old maternal age (OR, 1.04; 95% CI 1.02-1.07), multiple pregnancy (OR, 2.22; 95% CI 1.53-3.23), rheumatic disease (OR, 2.56; 95% CI 1.54-4.26), pregnancy induce hypertension (OR 6.02; 95% CI 3.61-10.05), preeclampsia (OR 24.66; 95% CI 18.61-32.66), eclampsia or superimposed preeclampsia (OR 32.74; 95% CI 21.60-49.64) and transfusion in previous pregnancy (OR 3.89; 95% CI 1.89-8.01). A scoring model to predict HFpEF with those factors achieved an area under the curve of 0.78 at cutoff value of 3. Women with HFpEF also had increased odds ratios of intensive care unit admission during the perinatal period (odds ratio, 5.98; 95% confidence interval, 4.36-8.21) and of postpartum hemorrhage (odds ratio, 5.98; 95% confidence interval, 2.02-3.64). CONCLUSIONS: Pregnancy-associated HFpEF is associated with adverse pregnancy outcomes. A scoring model may contribute to screening HFpEF using echocardiography and preparing adverse pregnancy outcomes.

Chromosomal Abnormality, fetal/neonatal Death and Socioeconomic Status: A Prospective Cohort Study.

OBJECTIVES: To assess the risk gradient of chromosomal abnormalities and fetal or neonatal death across a socioeconomic spectrum of pregnant women. METHODS: We used the data from the Korean Prenatal Diagnosis Study (KPDS), which included singleton pregnancies who were candidates for fetal aneuploidy screening enrolled from the Seoul Capital Area from December 2016 to April 2018. We analyzed chromosomal abnormalities which were diagnosed pre- or postnatally, and fetal or neonatal death. The highest level of education among the women and the average monthly household income were used as proxies for socioeconomic status. RESULTS: Among the 6,715 women, the majority of were 30-39 years old and university graduates, with a reported household income higher than the national median. Chromosomal abnormalities occurred in 45 women (6.7 per 1,000). Fetal or neonatal death occurred in 70 (11.3 per 1,000), excluding pregnancies affected by chromosomal abnormality diagnosis. The adjusted odds ratio for chromosomal abnormalities was higher when household income was < 4,484 USD per month. For fetal or neonatal death, the risk estimates for lower education and lower household income were generally positive but remained imprecise. CONCLUSION: We observed some evidence of an inverse association between the risk of fetal chromosomal abnormality and level of household income in a prospective cohort of pregnant women. Interventions to reduce socioeconomic disparities in perinatal health should focus on those with a low household income.

The Effect of Vanishing Twin on First- and Second-Trimester Maternal Serum Markers and Nuchal Translucency: A Multicenter Prospective Cohort Study.

BACKGROUND: The purpose of this study was to evaluate the effect of vanishing twin (VT) on maternal serum marker concentrations and nuchal translucency (NT). METHODS: This is a secondary analysis of a multicenter prospective cohort study in 12 institutions. Serum concentrations of pregnancy-associated plasma protein-A in the first trimester and alpha-fetoprotein (AFP), total human chorionic gonadotrophin, unconjugated estriol, and inhibin A in the second trimester were measured, and NT was measured between 10 and 14 weeks of gestation. RESULTS: Among 6,793 pregnant women, 5,381 women were measured for serum markers in the first or second trimester, including 65 cases in the VT group and 5,316 cases in the normal singleton group. The cases in the VT group had a higher median multiple of the median value of AFP and inhibin A than the normal singleton group. The values of other serum markers and NT were not different between the two groups. After the permutation test with adjustment, AFP and inhibin A remained significant differences. The frequency of abnormally increased AFP was also higher in the VT group than in the normal singleton group. CONCLUSION: VT can be considered as an adjustment factor for risk assessment in the second-trimester serum screening test.

Effects of polycyclic aromatic hydrocarbons on the proliferation and differentiation of placental cells.

BACKGROUND: The purpose of this study was to investigate the effects of polycyclic aromatic hydrocarbons (PAHs) other than bisphenol A (BPA) and BPA substitutes on placental cells. METHODS: HTR-8/SVneo cells were treated with anthracene, benzo[k]fluoranthene, benzo[a]pyrene, and 4,4-(9-fluorenylidene)diphenol, which is used as a substitute for BPA-free products. After confirming the dose response for each reagent using the prepared cells, the cells were incubated for 24, 48, and 72 h. Cell viability was confirmed using the XTT assay. Each experiment was performed with the minimum number of samples (n = 3) required for statistical analysis. The results were analyzed using t-tests; p < 0.05 was considered statistically significant. RESULTS: After treatment with anthracene, benzo[k]fluoranthene, benzo[a]pyrene, and 4,4-(9-fluorenylidene)diphenol, the absorbance measured using the XTT assay decreased significantly with increasing concentration. The absorbance decreased significantly over time following treatment with each endocrine disruptor at the concentration confirmed by the dose-response analysis. CONCLUSIONS: This study showed that anthracene, benzo[k]fluoranthene, benzo[a]pyrene, and 4,4-(9-fluorenylidene)diphenol-a BPA substitute-affect cell viability and necrosis in the placental cell line. The study indicates the serious effects of PAHs that negatively affect pregnancy but were previously unknown. Further, this study would serve as a reference for the identification of harmful PAHs during pregnancy prognosis in women who are more susceptible to PAH exposure.

The risk of preterm birth in women with history of short cervix delivering at term in the previous pregnancy: a retrospective cohort study.

PURPOSE: To investigate whether women with a short cervical length (CL), but delivered at term in the first pregnancy might have increased risks of having short cervix and spontaneous preterm birth (sPTB) in the subsequent pregnancies. METHODS: This is a retrospective cohort study including singleton gestations who were delivered between Jan 2011 and Dec 2018, who had had one childbirth experience and who had transvaginal sonographic CL assessment performed at mid-trimester (18 ~ 30 weeks) in both pregnancy. The women were divided into four group according to the history of preterm birth and a short cervix (< 25 mm before 30 weeks of gestation): (1) the Preterm-short cervix group, (2) the Preterm-no shortening group, (3) the Term-short cervix group, and (4) the Term-no shortening group. We compared the risk of having short cervix and sPTB during the second pregnancy of women. Secondary outcomes were threatened preterm labor, need for tocolytics, and cerclage placement. RESULTS: A total of 804 women met our inclusion criteria. The rate of having short cervix (< 25 mm before 28 weeks of gestation) during the second pregnancy in women in the Term-short cervix group (43.2%) was significantly higher than those in women in the Term-no shortening group (6.6%), and in the Preterm-no shortening group (8.8%) (all p < 0.001 with Bonferroni correction), but not higher than those in women with the Preterm-short cervix group (30.8%, p > 0.05 with Bonferroni correction). When compared with women in the Preterm-no shortening group, women in the Term-short cervix group were also at an increased risk of need for need of tocolytics (60.2% vs. 26.5%) and cerclage placement (15.9% vs. 6.1%, all p < 0.001). Women in the Term-short cervix group had an increased risk of sPTB (< 37 weeks) during the second pregnancy, as compared to those in the Term-no shortening group (adjusted odds ratio 5.098, 95% CI 2.107-11.874). CONCLUSION: Women with a history of short cervix in their first pregnancy, but who delivered at term, were at increased risk of having a short cervix and sPTB in their second pregnancy, as compared to women with a history of term delivery without cervical shortening. Thus, short cervix of the previous pregnancy might be a predictive factors for preterm birth in the subsequent pregnancy.

Ultrasonographic evaluation of ovarian mass for predicting malignancy in pregnant women.

OBJECTIVE: The purpose of this study is to compare ultrasonographic ovarian mass scoring systems in pregnant women. STUDY DESIGN: This multicenter study included women with an ovarian mass during pregnancy who were evaluated using ultrasound and underwent surgery in 11 referral hospitals. The ovarian mass was evaluated and scored using three different scoring systems(International Ovarian Tumor Analysis Assessment of Different NEoplasias in the adnexa[IOTA ADNEX], Sassone, and Lerner). The final diagnosis was made histopathologically. Receiver operating characteristic(ROC) curves were generated for each scoring system. RESULTS: During the study period, 236 pregnant women underwent surgery for an ovarian mass, including 223 women(94.5%) with a benign ovarian mass and 13 women(5.5%) with a malignant ovarian mass. Among 10 ultrasound image findings, six findings were different between benign and ovarian masses(maximal diameter of mass, maximal diameter of solid mass, wall thickness of mass, inner wall structure, thickness of septations, and papillarity). In all three scoring systems, the ovarian mass scores were significantly higher in malignant masses than in benign masses, with the highest area under the ROC curve(AUROC) in the Sassone scoring system(AUROC: 0.831 for Sassone, 0.710 for Lerner vs 0.709 for IOTA ADNEX; p < 0.05, between the Sassone and Lerner/ IOTA ADNEX). A combined model was developed with the six different ultrasound findings, and the AUROC of the combined model was 0.883(p = not significant between the combined model and Sassone). CONCLUSION: In pregnant women, malignant ovarian tumors can be predicted with high accuracy using either the Sassone scoring system or the combined model.

Influences of pregravid liver enzyme levels on the development of gestational diabetes mellitus.

BACKGROUND & AIMS: Elevated liver enzymes are associated with later development of type 2 diabetes mellitus. The objective of this study was to assess the association between prepregnancy liver enzyme levels and subsequent risk of gestational diabetes mellitus. METHODS: Data from a total of 236,109 women who participated in the National Health Screening Examination between 2011 and 2015 was analysed. Multivariate logistic regression analyses were performed to estimate the risk of developing gestational diabetes mellitus in relation to pregravid liver enzyme levels. Subgroup analyses were performed according to pregravid obesity and metabolic syndrome (MetS). RESULTS: Approximately 5.7% and 1.1% of women developed gestational diabetes mellitus with and without insulin treatment requirement respectively. Pregravid gamma-glutamyl transferase and alanine aminotransferase levels with greater than or equal to the 4th quartile were associated with significantly increased risks of gestational diabetes mellitus requiring insulin treatment in women with obesity and with MetS, (odds ratios [ORs] with 6.228 and 9.505, respectively, P < .001 for both). In women without obesity and without MetS, the risks of gestational diabetes mellitus requiring insulin treatment were also significant (ORs with 2.837 and 3.029, respectively, P < .001 for both). The elevated pregravid liver enzymes were associated with gestational diabetes mellitus without insulin treatment requirement, but minimally. CONCLUSIONS/INTERPRETATION: The elevated pregravid liver enzyme levels were significantly associated with the subsequent risk of gestational diabetes mellitus, especially gestational diabetes mellitus requiring insulin treatment, not only in women with obesity or MetS, but also in women without obesity or MetS.

Influenza vaccination during pregnancy and influencing factors in Korea: A multicenter questionnaire study of pregnant women and obstetrics and gynecology doctors.

BACKGROUND: Although the World Health Organization and health authorities in most countries recommend that pregnant women receive inactivated influenza virus vaccines, coverage remains low. This study aimed to investigate (1) the proportion of pregnant women who received an influenza vaccination and influencing factors and (2) the proportion of obstetrics and gynecology (OBGYN) doctors who routinely recommend influenza vaccination to pregnant women and influencing factors. METHODS: Two separate, anonymized questionnaires were developed for physicians and pregnant and postpartum women and were distributed to multicenters and clinics in South Korea. The proportions of women who received influenza vaccination during pregnancy and OBGYN doctors who routinely recommend the influenza vaccine to pregnant women were analyzed. Independent influencing factors for both maternal influenza vaccination and OBGYN doctors' routine recommendations to pregnant women were analyzed using log-binomial regression analysis. RESULTS: The proportion of self-reported influenza vaccination during pregnancy among 522 women was 63.2%. Pregnancy-related independent factors influencing maternal influenza vaccination were "(ever) received information about influenza vaccination during pregnancy" (OR 8.9, 95% CI 4.17-19.01), "received vaccine information about from OBGYN doctors" (OR 11.44, 95% CI 5.46-24.00), "information obtained from other sources" (OR 4.38, 95% CI 2.01-9.55), and "second/third trimester" (OR 2.41, 95% CI 1.21-4.82).. Among 372 OBGYN doctors, 76.9% routinely recommended vaccination for pregnant women. Independent factors effecting routine recommendation were "working at a private clinic or hospital" (OR 5.33, 95% CI 2.44-11.65), "awareness of KCDC guidelines" (OR 3.11, 95% CI 1.11-8.73), and "awareness of the 2019 national free influenza vaccination program for pregnant women" (OR 4.88, 95% CI 2.34-10.17). OBGYN doctors most commonly chose 'guidelines proposed by the government or public health (108, 46%) and academic committees (59, 25%), as a factor which expect to affect the future recommendation CONCLUSION: This study showed that providing information about maternal influenza vaccination, especially by OBGYN doctors, is crucial for increasing vaccination coverage in pregnant women. Closer cooperation between the government and OBGYN academic societies to educate OBGYN doctors might enhance routine recommendations.

Validation of a Strict Obesity Definition Proposed for Asians to Predict Adverse Pregnancy Outcomes in Korean Pregnant Women.

BACKGROUND: People are generally considered overweight and obese if their body mass index (BMI) is above 25 kg/m² and 30.0 kg/m², respectively. The World Health Organization proposed stricter criteria for Asians (≥ 23 kg/m²: overweight, ≥ 25 kg/m²: obese). We aimed to verify whether this criteria could predict adverse pregnancy outcomes in Korean women. METHODS: We included 7,547 Korean women from 12 institutions enrolled between June 2016 and October 2018. Women with no pre-pregnancy BMI data, not Korean, or lost to follow-up were excluded, leaving 6,331. The subjects were categorized into underweight, normal, overweight, class I obesity, and class II/III obesity based on a pre-pregnancy BMI of < 18.5, 18.5-22.9, 23.0-24.9, 25.0-29.9, and ≥ 30.0 kg/m², respectively. RESULTS: Overall, 13.4%, 63.0%, 11.8%, 9.1%, and 2.6% of women were underweight, normal, and overweight and had class I obesity and class II/III obesity, respectively. In the multivariable analysis adjusted for maternal age, a higher BMI significantly increased the risk of preeclampsia, gestational diabetes, preterm delivery caused by maternal-fetal indications, cesarean section, large for gestational age, and neonatal intensive care unit admission. CONCLUSION: Adverse pregnancy outcomes started to increase in those with a pre-pregnancy BMI ≥ 23.0 kg/m² after adjusting for maternal age. The modified obesity criteria could help predict adverse pregnancy outcomes in Koreans.

Nationwide population-based cohort study of adverse obstetric outcomes in pregnancies with myoma or following myomectomy: retrospective cohort study.

BACKGROUND: Our objective was to evaluate risks of adverse obstetric outcomes in pregnancies with myoma(s) or in pregnancies following myomectomy. METHODS: We analyzed the national health insurance database, which covers almost the entire Korean population, between 2004 and 2015. The risks of adverse pregnancy outcomes in pregnancies with myoma(s) or in pregnancies following myomectomy, compared to those in women without a diagnosed myoma, were analyzed in multivariate logistic regression analysis. RESULTS: During the study period, 38,402 women with diagnosed myoma(s), 9890 women with a history of myomectomy, and 740,675 women without a diagnosed myoma gave birth. Women with a history of diagnosed myoma(s) and women with a history of myomectomy had significantly higher risks of cesarean section (aOR 1.13, 95% CI 1.1-1.16 and aOR 7.46, 95% CI 6.97-7.98, respectively) and placenta previa (aOR 1.41, 95% CI 1.29-1.54 and aOR 1.58, 95% CI 1.35-1.83, respectively), compared to women without a diagnosed myoma. And the risk of uterine rupture was significantly higher in women with previous myomectomy (aOR 12.78, 95% CI 6.5-25.13), compared to women without a diagnosed myoma, which was much increased (aOR 41.35, 95% CI 16.18-105.69) in nulliparous women. The incidence of uterine rupture was the highest at delivery within one year after myomectomy and decreased over time after myomectomy. CONCLUSIONS: Women with a history of myomectomy had significantly higher risks of cesarean section and placenta previa compared to women without a diagnosed myoma.

Application of Tissue Engineering and Regenerative Medicine in Maternal-Fetal Medicine.

A rapid development of ultrasonography has enabled physicians to make earlier prenatal diagnosis of various fetal congenital diseases, in maternal-fetal medicine. Due to the significant mortality and irreversible damage to fetal vital organs during pregnancy, fetal surgeries have been tried in some congenital disease including congenital diaphragmatic hernia, twin-to-twin transfusion syndrome (TTTS), myelomeningocele (MMC), and lower urinary tract obstruction. However, open fetal surgery requires laparotomy followed by hysterotomy, which can cause preterm premature rupture of membrane (pPROM), oligohydramnios, preterm delivery, dehiscence of uterine wall, and other maternal complications during pregnancy. Minimally invasive approach using fetoscopy has been tried, and fetoscopic laser photocoagulation of vascular communications is currently considered as a treatment of choice for TTTS before 26 weeks' gestation. However, more development of surgical instrument and innovative materials using tissue engineering are required to improve outcomes of fetoscopic surgery. Because iatrogenic pPROM is the major challenge after fetoscopic surgery, this review focuses on current development of materials for treatment of spontaneous or iatrogenic pPROM and recent experimental progress of tissue engineering-based technology in prenatal treatment of MMC. Placental tissue is an emerging material for regenerative medicine. This chapter will also review regenerative potential and experiments of placenta and placenta-derived stem cells, as well as prospects of "in utero stem cell therapy."

Effect of Cervical Cerclage on the Risk of Recurrent Preterm Birth after a Twin Spontaneous Preterm Birth.

BACKGROUND: This study aimed to evaluate the effect of cervical cerclage on the recurrence risk for preterm birth in singleton pregnant women after a twin spontaneous preterm birth (sPTB). METHODS: This multicenter retrospective cohort study included women who had a singleton pregnancy from January 2009 to December 2018 at 10 referral hospitals and a twin sPTB before the current pregnancy. We compared the cervical lengths during pregnancy and pregnancy outcomes, according to the placement of prophylactic or emergency cerclage. We evaluated the independent risk factors for sPTB (< 37 weeks of gestation) in a subsequent singleton pregnancy. RESULTS: For the index singleton pregnancy, preterm birth occurred in seven (11.1%) of 63 women. There was no significant difference in the cervical lengths during pregnancy in women with and without cerclage. In a multivariate logistic regression analysis, the placement of emergency cerclage was an independent risk factor for subsequent singleton preterm birth (odds ratio [OR], 93.188; 95% confidence interval [CI], 1.633-5,316.628; P = 0.027); however, the placement of prophylactic cerclage (OR, 19.264; 95% CI, 0.915-405.786; P = 0.057) was not a factor. None of the women who received prophylactic cerclage delivered before 35 weeks' gestation in the index singleton pregnancy. CONCLUSION: Cerclage did not lower the risk of preterm birth in a subsequent singleton pregnancy after a twin sPTB. However, emergency cerclage was an independent risk factor for preterm birth and there was no preterm birth before 35 weeks' gestation in the prophylactic cerclage group. Therefore, close monitoring of the cervical length and prophylactic cerclage might be considered in women who have experienced a twin sPTB at extreme gestation.

Gestational age-specific risk of stillbirth during term pregnancy according to maternal age.

PURPOSE: To investigate the gestational age-specific risk of stillbirth according to the maternal age group particularly regarding stillbirth risk at the end of pregnancy. METHODS: This study was a retrospective national cohort study of all singleton term pregnancy using the Korean Vital Statistics database (n = 2,798,542). We evaluated the risk of stillbirth by gestational week in mothers aged 20-49 years according to maternal age group and neonatal birth weight. RESULTS: The risk of stillbirth in women aged 41 years and older was significantly higher than in women aged 20-29 years between 37 and 40 weeks' gestation. The stillbirth rate per 10,000 ongoing pregnancy in women aged 37-38 years at 39 weeks' gestation (4.22, 95% confidence intervals [CI] 3.01-5.90) and that in women aged 39-40 years at 40 weeks' gestation (8.15, 95% CI 4.83-13.77) were significantly higher in comparison with in those aged 20-29 years at 39 weeks' gestation (1.95, 95% CI 1.64-2.33) and at 40 weeks' gestation (2.59, 95% CI 2.1-3,18). The risk of stillbirth showed an increasing pattern at 40 gestational weeks, in women aged 39 years and older. CONCLUSIONS: Delivery plan need to be set up and supported to decrease rates of stillbirth at term in women aged 35 years and older with other risk factors and in women aged 37 years and older regardless of risk factors, and especially in women older than 40 years of age.

The Educational Effects of a Pregnancy Simulation in Medical/Nursing Students and Professionals.

BACKGROUND: The objective of this study was to investigate whether a pregnancy experience program (PREP) simulating physical changes in a mother during the last trimester of pregnancy could increase empathy, understanding, and positive attitude of medical/nursing students and their professional counterparts. METHODS: This was a prospective observational study on medical/nursing students and their professional counterparts. Jefferson Scale of Physician Empathy (JSPE), physical difficulty and positive attitude score, and perceived effectiveness scores prior to PREP were compared to those after PREP. RESULTS: A total of 189 participants completed PREP and questionnaires both prior to and after PREP. Mean JSPE score, physical difficulty score, and positive attitude scores were significantly increased following PREP (p<0.001, all). Perceived effectiveness scores about awareness, empathy, and understanding after PREP were significantly high in the professional group than in the student group (p=0.004, p=0.01, and p=0.017, respectively). Multiple stepwise linear regression analysis revealed that major in medicine (p = 0.014), health care professionals (nurse or physician) (p<0.001), and marriage experience (p < 0.001) were significant predictors of increasing empathy, difficulty feelings and effectiveness scores, respectively. CONCLUSION: PREP is an effective simulation program that can improve empathy, positive attitude, and awareness in medical/nursing students as well as their professional counterparts.

Hydrogel-Mediated DOX⋠HCl/PTX Delivery System for Breast Cancer Therapy.

We used a hydrogel-mediated dual drug delivery approach, based on an injectable glycol chitosan (GC) hydrogel, doxorubicin hydrochloride (DOX⋅HCl), and a complex of beta-cyclodextrin (ß-CD) and paclitaxel (PTX) (GDCP) for breast cancer therapy in vitro and in vivo. The hydrogel was swollen over 3 days and remained so thereafter. After an initial burst period of 7 hours, the two drugs were released in a sustained manner for 7 days. The in vitro cell viability test showed that GDCP had a better anticancer effect than well plate and DOX⋅HCl/PTX (DP). In addition, the in vivo tests, which evaluated the anticancer effect, systemic toxicity, and histology, proved the feasibility of GDCP as a clinical therapy for breast cancer.

A missense mutation in EBF2 was segregated with imperforate anus in a family across three generations.

The etiology of imperforate anus, a major phenotype of anorectal malformation (ARM), is still unknown and not a single gene has been reported to be associated with it. We studied a Korean family with six affected members with imperforate anus across three generations by whole exome sequencing and identified a missense mutation in the EBF2 gene (c.215C > T; p.Ala72Val). This mutation is completely segregated with the disease phenotype in the family and is evolutionarily highly conserved among diverse vertebrates. Also, this mutation was predicted to be functionally damaging. These results support that missense mutation in the EBF2 c.215C > T (p.Ala72Val) is very likely to contribute to the pathogenesis of ARM in this family.

Prospective observations study protocol to investigate cost-effectiveness of various prenatal test strategies after the introduction of noninvasive prenatal testing.

BACKGROUND: 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. METHODS/DESIGN: 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. DISCUSSION: 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.

Optimal Timing of Delivery Based on the Risk of Stillbirth and Infant Death Associated with Each Additional Week of Expectant Management in Multiple Pregnancies: a National Cohort Study of Koreans.

BACKGROUND: The purpose of this study was to compare the fetal/infant mortality risk associated with each additional week of expectant management to that associated with immediate delivery in women with multiple gestations. METHODS: This was a retrospective national cohort study of 94,170 multiple deliveries, 92,619 (98.4%) twin and 1,352 (1.44%) triplet pregnancies, between 32 0/7 and 42 6/7 weeks of gestation recorded in the Korean vital statistics database. We investigated the risks of stillbirth and infant death after birth in Korea according to the week of gestation in twin and triplet pregnancies. RESULTS: The risk of stillbirth significantly increased between 34 and 35 weeks of gestation and between 37 and 38 weeks of gestation in twin pregnancies and between 34 and 37 weeks of gestation in triplet pregnancies. The risk of infant death following delivery gradually decreased as pregnancies approached full term. Week-by-week differences were statistically significant between 33 and 34 weeks, with decreasing risks of infant death at advancing gestational ages in twin pregnancies. At 37 weeks of gestation, the relative risk of mortality was significantly higher with expectant management compared with immediate delivery (relative risk, 3.00; 95% confidence interval, 1.41-6.38). CONCLUSION: In twin pregnancies, delivery at 37 weeks of gestation can minimize the risks of stillbirth and infant death in uncomplicated cases, although individual maternal and fetal characteristics must be considered when determining the optimal timing of delivery. In multiple pregnancies, close fetal surveillance is needed after 34 weeks of gestation.

Determining optimal gestational weight gain in the Korean population: a retrospective cohort study.

BACKGROUND: The World Health Organization (WHO) international body mass index (BMI) cut-off points defining pre-pregnancy BMI categories in the Institute of Medicine (IOM) guidelines are not directly applicable to Asians. We aimed to define the optimal gestational weight gain (GWG) for the Korean population based on Asia-specific BMI categories. METHODS: Data from 2702 live singleton deliveries in three tertiary centers between 2010 and 2011 were analyzed retrospectively. A multivariable logistic regression analysis was conducted to determine the lowest aggregated risk of composite perinatal outcomes based on Asia-specific BMI categories. The perinatal outcomes included gestational hypertensive disorder, emergency cesarean section, and fetal size for gestational age. In each BMI category, the GWG value corresponding to the lowest aggregated risk was defined as the optimal GWG. RESULTS: Among the study population, 440 (16.3%) were underweight (BMI < 18.5), 1459 (54.0%) were normal weight (18.5 ≤ BMI < 23), 392 (14.5%) were overweight (23 ≤ BMI < 25) and 411 (15.2%) were obese (BMI ≥ 25). The optimal GWG by Asia-specific BMI category was 20.8 kg (range, 16.7 to 24.7) for underweight, 16.6 kg (11.5 to 21.5) for normal weight, 13.1 kg (8.0 to 17.7) for overweight, and 14.4 kg (7.5 to 21.9) for obese. CONCLUSION: Considerably higher and wider optimal GWG ranges than recommended by IOM are found in our study in order to avoid adverse perinatal outcomes. Revised IOM recommendations for GWG could be considered for Korean women according to Asian BMI categories. Further prospective studies are needed in order to determine the optimal GWG for the Korean population.

Prevalence of Low Bone Mineral Density and Associated Risk Factors in Korean Puerperal Women.

Although pregnancy is a medical condition that contributes to bone loss, little information is available regarding bone mineral density (BMD) in puerperal women. This cross sectional study aimed to evaluate the prevalence of low BMD in puerperal women and to identify associated risk factors. We surveyed all puerperal women who had BMD measurements taken 4-6 weeks after delivery in a tertiary university hospital, and did not have any bone loss-related comorbidities. Among the 1,561 Korean puerperal women, 566 (36.3%) had low BMD at the lumbar spine, total hip, femoral neck, and/or trochanter. Multivariate analysis revealed that underweight women had a significantly higher risk of low BMD compared with obese women at pre-pregnancy (adjusted odds ratio [aOR], 3.21; 95% confidence interval [CI], 1.83-5.63). Also, women with inadequate gestational weight gain (GWG) were 1.4 times more likely to have low BMD than women with excessive GWG (aOR, 1.42; 95% CI, 1.04-1.94). One-way ANOVA showed that BMDs at the lumbar spine and total hip were significantly different between the 4 BMI groups (both P < 0.001) and also between the 3 GWG groups (both P < 0.001). In conclusion, this study identifies a high prevalence of low BMD in puerperal women and thus suggests the need for further evaluation about the change of BMD in pregnancy and postpartum period.