Maternal obesity, interpregnancy weight changes and congenital heart defects in the offspring: a nationwide cohort study.

OBJECTIVE: To evaluate the association between maternal BMI and congenital heart defects (CHDs) in the offspring when including live births, stillbirths, aborted and terminated pregnancies and to investigate if maternal interpregnancy weight changes between the first and second pregnancy influences the risk of foetal CHDs. METHODS: A nationwide cohort study of all singleton pregnancies in Denmark from 2008 to 2018. Data were retrieved from the Danish Foetal Medicine Database, which included both pre- and postnatal diagnoses of CHDs. Children or foetuses with chromosomal aberrations were excluded. Odds ratios were calculated with logistic regression models for CHDs overall, severe CHDs and five of the most prevalent subtypes of CHDs. RESULTS: Of the 547 105 pregnancies included in the cohort, 5 442 had CHDs (1.0%). Risk of CHDs became gradually higher with higher maternal BMI; for BMI 25-29.9 kg/m2, adjusted odds ratio (aOR) 1.17 (95% CI 1.10-1.26), for BMI 30-34.9 kg/m2, aOR 1.21 (95% CI 1.09-1.33), for BMI 35-39.9 kg/m2, aOR 1.29 (95% CI 1.11-1.50) and for BMI ≥ 40 kg/m2, aOR 1.85 (95% CI 1.54-2.21). Data was adjusted for maternal age, smoking status and year of estimated due date. The same pattern was seen for the subgroup of severe CHDs. Among the atrioventricular septal defects (n = 231), an association with maternal BMI ≥ 30 kg/m2 was seen, OR 1.67 (95% CI 1.13-2.44). 109 654 women were identified with their first and second pregnancies in the cohort. Interpregnancy BMI change was associated with the risk of CHDs in the second pregnancy (BMI 2 to < 4 kg/m2: aOR 1.29, 95% CI 1.09-1.53; BMI ≥ 4 kg/m2: aOR 1.36, 95% CI 1.08-1.68). CONCLUSION: The risk of foetal CHDs became gradually higher with higher maternal BMI and interpregnancy weight increases above 2 BMI units were also associated with a higher risk of CHDs.

Impact of an Impaired Maternal-Fetal Environment on Death in Children With Congenital Heart Defects Undergoing Surgery in Denmark From 1994 to 2018.

BACKGROUND: Studies show that an impaired maternal-fetal environment (iMFE) increases the mortality risk in children with single-ventricle congenital heart defects (CHDs). We investigated the impact of an iMFE on death in children with various surgically corrected CHDs. METHODS AND RESULTS: In this nationwide register-based study, we examined the association between an iMFE (including preeclampsia, gestational hypertension, gestational diabetes, maternal smoking during pregnancy) and death in a large cohort of children with surgically corrected CHDs in Denmark (1994-2018). Survival analysis was done using Cox regression, adjusted for confounding and mediating covariates. The cohort included 3304 children: 1662 (50.3%) with minor CHD and 1642 (49.7%) with major CHD. Among them, 792 (24%) children were exposed to an iMFE. During the study, there were 290 deaths: 71 (9.3%) in children exposed to an iMFE and 219 (8.7%) in those unexposed. There were no differences in mortality risk between children with CHD exposed to an iMFE and those unexposed (hazard ratio [HR], 1.12 [95% CI, 0.86-1.47]; P=0.4). This was consistent across subgroups, including minor CHD (HR, 0.76 [95% CI, 0.39-1.47]; P=0.4), major CHD (HR, 1.23 [95% CI, 0.92-1.64]; P=0.2), and hypoplastic left heart syndrome/univentricular heart (HR, 1.08 [95% CI, 0.64-1.85]; P=0.8). CONCLUSIONS: Impairment of the maternal-fetal environment did not impact the mortality rate in children with CHD undergoing operation in Denmark from 1994 to 2018. We believe the cause of these discrepant findings to previous studies may be due to differences in the composition of CHD and prenatal maternal health care and health status of the population.

Increased nuchal translucency in children with congenital heart defects and normal karyotype-is there a correlation with mortality?

Objectives: Our objective was to investigate if an increased nuchal translucency (NT) was associated with higher mortality in chromosomally normal children with congenital heart defects (CHD). Methods: In a nationwide cohort using population-based registers, we identified 5,633 liveborn children in Denmark with a pre- or postnatal diagnosis of CHD from 2008 to 2018 (incidence of CHD 0.7%). Children with chromosomal abnormalities and non-singletons were excluded. The final cohort compromised 4,469 children. An increased NT was defined as NT > 95th-centile. Children with a NT > 95th-centile vs. NT < 95th-centile including subgroups of simple- and complex CHD were compared. Mortality was defined as death from natural causes, and mortalities were compared among groups. Survival analysis with Cox-regression was used to compare rates of mortality. Analyses were adjusted for mediators (possibly explanatory factors between increased NT and higher mortality): preeclampsia, preterm birth and small for gestational age. And for confounding effects of extracardiac anomalies and cardiac intervention, due to their close association to both the exposure and the outcome (i.e., confounders). Results: Of the 4,469 children with CHD, 754 (17%) had complex CHD and 3,715 (83%) simple CHD. In the combined group of CHDs the mortality rate was not increased when comparing those with a NT > 95th-centile to those with a NT < 95th-centile [Hazard ratio (HR) 1.6, 95%CI 0.8;3.4, p = 0.2]. In simple CHD there was a significantly higher mortality rate with a HR of 3.2 (95%CI: 1.1;9.2, p = 0.03) when having a NT > 95th centile. Complex CHD had no differences in mortality rate between a NT > 95th-centile and NT < 95th-centile (HR 1.1, 95%CI: 0.4;3.2, p = 0.8). All analysis adjusted for severity of CHD, cardiac operation and extracardiac anomalies. Due to limited numbers the association to mortality for a NT > 99th centile (>3.5 mm) could not be assessed. Adjustment for mediating (preeclampsia, preterm birth, small for gestational age) and confounding variables (extracardiac anomalies, cardiac intervention) did not alter the associations significantly, except for extracardiac anomalies in simple CHD. Conclusion: An increased NT > 95th-centile is correlated with higher mortality in children with simple CHD, but the underlying cause is unknown and undetected abnormal genetics might explain the correlation rather than the increased NT itself, hence further research is warranted.

First-trimester prediction of preterm prelabour rupture of membranes incorporating cervical length measurement.

OBJECTIVES: To examine early pregnancy risk factors for preterm prelabour rupture of membranes (PPROM) and develop a predictive model. STUDY DESIGN: Retrospective analysis of a cohort of mixed-risk singleton pregnancies screened in the first and second trimesters in three Danish tertiary fetal medicine centres, including a cervical length measurement at 11-14 weeks, at 19-21 weeks and at 23-24 weeks of gestation. Univariable and multivariable logistic regression analyses were employed to identify predictive maternal characteristics, biochemical and sonographic factors. Receiver operating characteristic (ROC) curve analysis was used to determine predictors for the most accurate model. RESULTS: Of 3477 screened women, 77 (2.2%) had PPROM. Maternal factors predictive of PPROM in univariable analysis were nulliparity (OR 2.0 (95% CI 1.2-3.3)), PAPP-A < 0.5 MoM (OR 2.6 (1.1-6.2)), previous preterm birth (OR 4.2 (1.9-8.9)), previous cervical conization (OR 3.6 (2.0-6.4)) and cervical length ≤ 25 mm on transvaginal imaging (first-trimester OR 15.9 (4.3-59.3)). These factors all remained statistically significant in a multivariable adjusted model with an AUC of 0.72 in the most discriminatory first-trimester model. The detection rate using this model would be approximately 30% at a false-positive rate of 10%. Potential predictors such as bleeding in early pregnancy and pre-existing diabetes mellitus affected very few cases and could not be formally assessed. CONCLUSIONS: Several maternal characteristics, placental biochemical and sonographic features are predictive of PPROM with moderate discrimination. Larger numbers are required to validate this algorithm and additional biomarkers, not currently used for first-trimester screening, may improve model performance.

A Rare Dichorionic Triamniotic Triplet Pregnancy with Spontaneous Twin Anemia-Polycythemia Sequence between Two Dichorionic Fetuses.

INTRODUCTION: This report presents a rare case of spontaneous twin anemia-polycythemia sequence (TAPS) between two dichorionic fetuses in a spontaneous, homozygotic, dichorionic, triamniotic, triplet pregnancy treated with multiple intrauterine blood transfusions (IUTs) and partial exchange transfusions (PETs). CASE PRESENTATION: The pregnancy was diagnosed with stage IV TAPS at gestational week 25+1. The patient was treated with laser surgery combined with multiple IUTs and PETs. The triplets were delivered at a planned caesarean section at gestational week 28+1 with postnatal hemoglobin values of 18.21, 26.43, and 11.92 g/dL in triplet 1, 2, and 3, respectively. At 4 years of age, triplet 1 is considered healthy, triplet 2 is diagnosed with mild mental retardation, and triplet 3 with profound mental retardation and dystonic cerebral palsy. DISCUSSION: This is an extremely rare case of TAPS between dichorionic fetuses in a triplet pregnancy, and routine surveillance with measurement of middle cerebral artery peak systolic velocity in dichorionic pregnancies may contribute to the detection of similar cases in the future. Furthermore, this case contributes with rare long-term follow-up data of children treated for high-stage TAPS with multiple IUTs and PETs.

Magnetic Resonance Imaging: A New Tool to Optimize the Prediction of Fetal Anemia?

INTRODUCTION: The false-positive rate in the prediction of fetal anemia is 10-15%. We investigated if a new, noninvasive MRI method used as a supplement to ultrasound could improve the prediction. METHODS: Fetuses suspected of anemia and controls were scanned in a 1.5-tesla MRI scanner 1-4 times during pregnancy. Cases were scanned before and after intrauterine blood transfusion with a T1-mapping MRI sequence in a cross-section of the umbilical vein. RESULTS: Inclusion of 8 cases and 11 controls resulted in 10 case scans (2 cases were included twice) and 33 control scans. In controls, the T1 relaxation time was 1,005-1,391 ms; in cases with severe anemia, 1,505-1,595 ms, moderate anemia 1,503-1,525 ms, and no/mild anemia 1,245-1,410 ms. After blood transfusions, values dropped to 1,123-1,288 ms. The mean value in moderate and severe anemic cases was 275 ms higher than in controls (95% CI 210-341 ms, p < 0.0001), and after blood transfusion it was comparable to controls (3 ms, 95% CI -62 to 68 ms, p = 0.934). A 1,450-ms cut-off would have identified all cases in need of blood transfusion with no false-positive cases. CONCLUSIONS: Our findings indicate a potential for this new MRI method to improve the prediction of fetal anemia as a supplement to ultrasound.

Parental Decisions about Prenatal Screening and Diagnosis among Infants with Trisomy 21 in a National Cohort with High Uptake of Combined First-Trimester Screening.

INTRODUCTION: The aim was to investigate the parental decisions about prenatal screening and diagnosis among infants with trisomy 21 (T21) in a national cohort with high uptake of combined first-trimester screening (cFTS). MATERIAL AND METHODS: This was a nationwide population-based study including infants born in 2009-2012. Information from the cFTS, fetal karyotype results and pregnancy outcome was obtained from the Danish Fetal Medicine Database on all women with a cFTS risk assessment. Cut-off for referral for invasive testing was ≥1:300. Karyotype results from pregnancies with no cFTS were obtained from the Danish Cytogenetic Central Registry. RESULTS: The uptake rate of cFTS was 91.6%, and 82.8% (8,032/9,704) of the screen-positive women opted for invasive testing. Overall, 82.2% (454/552) chose to terminate an affected pregnancy. In the 4-year period, 102 of 232,962 singletons were born alive with T21. The cFTS risk was true-positive, false-negative or not obtained in 21.6, 48.0 and 30.4%, respectively, of these pregnancies. DISCUSSION: In this large national cohort, 4.4 per 10,000 live-born infants had T21. Of 102 infants with T21 from 2009 to 2012, 52.0% were born after the women had not opted for cFTS or were true-positive but declined invasive testing or termination, and 48.0% were born after a false-negative risk assessment.

Nuchal translucency distributions for different chromosomal anomalies in a large unselected population cohort.

OBJECTIVE: To describe the distribution of the fetal nuchal translucency thickness (NT) according to type of chromosomal aberration in a large unselected population. METHODS: Data on pregnancies with an NT measurement performed at gestational age 11 + 3 - 13 + 6 weeks from 2008 to 2011 were retrieved from the Danish National Fetal Medicine Database. Information on any genetic analysis for aneuploidy performed pre- or postnatally was also obtained. The abnormal results were grouped into 14 types of chromosomal anomalies. Distributions of NT measurements were summarized by aberration and compared with the normal/no karyotype group. RESULTS: A total of 215 223 singleton pregnancies were included in the cohort; 10548 had a normal karyotype and 1286 had an aberration. Plots of the NT measurements showed that like trisomy 21, 18 and 13 and monosomy X, the distribution for the unbalanced translocations was shifted towards larger NTs. The distributions for the balanced translocations, the uncommon trisomies and the triploidies more closely resembled that of the normal/no karyotype population. CONCLUSION: Fetuses with aneuploidies have NT distributions visually different from normal fetuses, with the exception of triploidies and uncommon autosomal trisomies. The distributions differ in shape according to type of chromosomal anomaly. © 2015 John Wiley & Sons, Ltd.

The Danish Fetal Medicine Database: establishment, organization and quality assessment of the first trimester screening program for trisomy 21 in Denmark 2008-2012.

OBJECTIVE: To describe the establishment and organization of the Danish Fetal Medicine Database and to report national results of first-trimester combined screening for trisomy 21 in the 5-year period 2008-2012. DESIGN: National register study using prospectively collected first-trimester screening data from the Danish Fetal Medicine Database. POPULATION: Pregnant women in Denmark undergoing first-trimester screening for trisomy 21. METHODS: Data on maternal characteristics, biochemical and ultrasonic markers are continuously sent electronically from local fetal medicine databases (Astraia Gmbh software) to a central national database. Data are linked to outcome data from the National Birth Register, the National Patient Register and the National Cytogenetic Register via the mother's unique personal registration number. First-trimester screening data from 2008 to 2012 were retrieved. MAIN OUTCOME MEASURES: Screening performance was assessed for the years 2008-2012 by calculating detection rates and screen-positive rates. RESULTS: A total of 268 342 first-trimester risk assessments for trisomy 21 were performed in singleton pregnancies. Participation rate in first-trimester screening was >90%. The national screen-positive rate increased from 3.6% in 2008 to 4.7% in 2012. The national detection rate of trisomy 21 was reported to be between 82 and 90% in the 5-year period. CONCLUSION: A national fetal medicine database has been successfully established in Denmark. Results from the database have shown that at a national level first-trimester screening performance for trisomy 21 is high with a low screen-positive rate and a high detection rate.

Impact of type 1 diabetes and glycemic control on fetal aneuploidy biochemical markers.

OBJECTIVE: To determine the influence of type 1 diabetes mellitus (T1DM) on the first trimester serum markers of fetal aneuploidy; pregnancy-associated plasma protein-A (PAPP-A) and free beta subunit of human chorionic gonadotropin (free ß-hCG) and to evaluate the influence of glycemic control on these parameters in the pregnant diabetic women. DESIGN: Retrospective study. SETTING: Data were extracted from electronic obstetric and laboratory databases at two Danish University Hospitals. POPULATION: Based on 36 415 pregnancies without T1DM (non-T1DM) and 331 pregnancies with T1DM; ß-hCG and PAPP-A were obtained at 8+0 to 14+2 gestational weeks. METHODS: Medians for PAPP-A and free ß-hCG were generated and multiple of the normal gestation-specific median (MoM) values were calculated for each separate pregnancy. After adjustment for maternal weight, ethnicity and smoking status, MoM values were compared across the T1DM and non-T1DM groups, respectively. Additionally, the relationship between PAPP-A MoM and HgbA1C was examined in 348 T1DM pregnancies by Spearman's rank correlation. MAIN OUTCOME MEASURES. Difference in biochemical marker levels between T1DM and non-T1DM. RESULTS: PAPP-A was 0.86 MoM in T1DM pregnancies and 1.01 MoM in non-T1DM pregnancies, p < 0.0001. Conversely, free ß-hCG was not altered in T1DM pregnancies (T1DM 0.99 MoM, non-T1DM 0.98 MoM; p=0.14). There was a significant inverse correlation between HgbA1C and PAPP-A (rho=-0.12, p=0.02). CONCLUSIONS: In T1DM pregnancies, PAPP-A MoM values were lower than in non-T1DM pregnancies. This suggests that correction should be considered in first trimester biochemical screening for fetal aneuploidy in T1DM women.

Can a 15-mm cervical length cutoff discriminate between low and high risk of preterm delivery in women with threatened preterm labor?

OBJECTIVES: To investigate if a cervical length (CL) cutoff of 15 mm is relevant to use in women with threatened preterm labor. METHODS: From 2006 to 2009, 146 women with singleton pregnancies were admitted with threatened preterm labor between 23 and 33+6 weeks of gestation at Copenhagen University Hospital. Transvaginal sonographic measurement of CL was carried out on admission. Outcome measures were spontaneous delivery within 48 h, within 7 days and delivery before 34 weeks according to a CL cutoff of 15 mm. RESULTS: CL was <15 mm in 36 women (24.7%) and ≥15 mm in 110 women (75.3%). Spontaneous delivery occurred within 48 h or 7 days of presentation and before 34 weeks in 25, 38.9 and 50.0% of women with CL <15 mm and 3.6, 9.1 and 11.8% of women with CL ≥15 mm, respectively. The 15-mm CL cutoff had a sensitivity, false positive rate and negative predictive value for delivery within 48 h of 69.0, 20.3 and 96.4%, and within 7 days of 58.3, 18.1 and 90.9%. Women with CL <15 mm had odds of delivery within 7 days of 6.4 (95% CI 2.5-16.2). CONCLUSION: Although a 15-mm CL defines a group of women at high risk of spontaneous preterm delivery, 10 out of 110 women (9.1%) with a CL ≥15 mm deliver within 7 days.

Impact of a new national screening policy for Down's syndrome in Denmark: population based cohort study.

OBJECTIVES: To evaluate the impact of a screening strategy in the first trimester, introduced in Denmark during 2004-6, on the number of infants born with Down's syndrome and the number of chorionic villus samplings and amniocenteses, and to determine detection and false positive rates in the screened population in 2005 and 2006. DESIGN: Population based cohort study. SETTING: 19 Danish departments of gynaecology and obstetrics and a central cytogenetic registry 2000-7. PARTICIPANTS: 65 000 pregnancies per year. MAIN OUTCOME MEASURES: The primary outcomes measured were number of fetuses and newborn infants with Down's syndrome diagnosed prenatally and postnatally and number of chorionic villus samplings and amniocenteses carried out. Secondary outcomes measured were number of women screened in 2005 and 2006, screen positive rate, and information on screening in 2005 and 2006 for infants with a postnatal diagnosis of Down's syndrome. RESULTS: The number of infants born with Down's syndrome decreased from 55-65 per year during 2000-4 to 31 in 2005 and 32 in 2006. The total number of chorionic villus samplings and amniocenteses carried out decreased from 7524 in 2000 to 3510 in 2006. The detection rate in the screened population in 2005 was 86% (95% confidence interval 79% to 92%) and in 2006 was 93% (87% to 97%). The corresponding false positive rates were 3.9% (3.7% to 4.1%) and 3.3% (3.1% to 3.4%). CONCLUSION: The introduction of a combined risk assessment during the first trimester at a national level in Denmark halved the number of infants born with Down's syndrome. The strategy also resulted in a sharp decline in the number of chorionic villus samplings and amniocenteses carried out, even before full implementation of the policy.

Effects of blood sample handling procedures on measurable inflammatory markers in plasma, serum and dried blood spot samples.

The interests in monitoring inflammation by immunoassay determination of blood inflammatory markers call for information on the stability of these markers in relation to the handling of blood samples. The increasing use of stored biobank samples for such ventures that may have been collected and stored for other purposes, justifies the study hereof. Blood samples were stored for 0, 4, 24, and 48 h at 4 degrees C, room temperature (RT), and at 35 degrees C, respectively, before they were separated into serum or plasma and frozen. Dried blood spot samples (DBSS) were stored for 0, 1, 2, 3, 7, and 30 days at the same temperatures. 27 inflammatory markers in serum and plasma and 25 markers in DBSS were measured by a previously validated multiplex sandwich immunoassay using Luminex xMAP technology. The measurable concentrations of several cytokines in serum and plasma were significantly increased when blood samples were stored for a period of time before the centrifugation, for certain cytokines more than 1000 fold compared to serum and plasma isolated and frozen immediately after venepuncture. The concentrations in serum generally increased more than in plasma. The measurable concentrations of inflammatory markers also changed in DBSS stored under various conditions compared to controls frozen immediately after preparation, but to a much lesser degree than in plasma or serum. The study demonstrates that trustworthy measurement of several inflammatory markers relies on handling of whole blood samples at low temperatures and rapid isolation of plasma and serum. Effects of different handling procedures for all markers studied are given. DBSS proved to be a robust and convenient way to handle samples for immunoassay analysis of inflammatory markers in whole blood.