Patient-reported barriers to prenatal diagnosis of congenital heart defects: A mixed-methods study

OBJECTIVE

To ascertain patient-reported, modifiable barriers to prenatal diagnosis of congenital heart defects (CHDs).

METHODS

This was a mixed-methods study among caretakers of infants who received congenital heart surgery from 2019 to 2020 in the Chicagoland area. Quantitative variables measuring sociodemographic characteristics and prenatal care utilization, and qualitative data pertaining to patient-reported barriers to prenatal diagnosis were collected from electronic health records and semi-structured phone surveys. Thematic analysis was performed using a convergent parallel approach.

RESULTS

In total, 160 caretakers completed the survey, 438 were eligible for survey, and 49 (31%) received prenatal care during the COVID-19 pandemic. When comparing respondents and non-respondents, there was a lower prevalence of maternal Hispanic ethnicity and a higher prevalence of non-English/Spanish-speaking households. Of all respondents, 34% reported an undetected CHD on ultrasound or echocardiogram, while 79% reported at least one barrier to prenatal diagnosis related to social determinants of health. Among those social barriers, the most common were difficulty with appointment scheduling (n = 12, 9.5%), far distance to care/lack of access to transportation (n = 12, 9.5%) and difficulty getting time off work to attend appointments (n = 6, 4.8%). The latter two barriers were correlated.

CONCLUSION

While technical improvements in the detection of CHDs remain an important area of research, it is equally critical to produce evidence for interventions that mitigate barriers to prenatal diagnosis due to social determinants of health.

Maternal Nativity and Preterm Birth

Importance

Preterm birth is a major contributor to neonatal morbidity and mortality, and considerable differences exist in rates of preterm birth among maternal racial and ethnic groups. Emerging evidence suggests pregnant individuals born outside the US have fewer obstetric complications than those born in the US, but the intersection of maternal nativity with race and ethnicity for preterm birth is not well studied.

Objective

To determine if there is an association between maternal nativity and preterm birth rates among nulliparous individuals, and whether that association differs by self-reported race and ethnicity of the pregnant individual.

Design, Setting, and Participants

This was a nationwide, cross-sectional study conducted using National Center for Health Statistics birth registration records for 8 590 988 nulliparous individuals aged 15 to 44 years with singleton live births in the US from 2014 to 2019. Data were analyzed from March to May 2022.

Exposures

Maternal nativity (non-US-born compared with US-born individuals as the reference, wherein US-born was defined as born within 1 of the 50 US states or Washington, DC) in the overall sample and stratified by self-reported ethnicity and race, including non-Hispanic Asian and disaggregated Asian subgroups (Asian Indian, Chinese, Filipino, Japanese, Korean, Pacific Islander, Vietnamese, and other Asian), non-Hispanic Black, Hispanic and disaggregated Hispanic subgroups (Cuban, Mexican, Puerto Rican, and other Hispanic), and non-Hispanic White.

Main Outcomes and Measures

The primary outcome was preterm birth (<37 weeks of gestation) and the secondary outcome was very preterm birth (<32 weeks of gestation).

Results

Of 8 590 988 pregnant individuals included (mean [SD] age at delivery, 28.3 [5.8] years in non-US-born individuals and 26.2 [5.7] years in US-born individuals; 159 497 [2.3%] US-born and 552 938 [31.2%] non-US-born individuals self-identified as Asian or Pacific Islander, 1 050 367 [15.4%] US-born and 178 898 [10.1%] non-US-born individuals were non-Hispanic Black, 1 100 337 [16.1%] US-born and 711 699 [40.2%] non-US-born individuals were of Hispanic origin, and 4 512 294 [66.1%] US-born and 328 205 [18.5%] non-US-born individuals were non-Hispanic White), age-standardized rates of preterm birth were lower among non-US-born individuals compared with US-born individuals (10.2%; 95% CI, 10.2-10.3 vs 10.9%; 95% CI, 10.9-11.0) with an adjusted odds ratio (aOR) of 0.90 (95% CI, 0.89-0.90). The greatest relative difference was observed among Japanese individuals (aOR, 0.69; 95% CI, 0.60-0.79) and non-Hispanic Black individuals (aOR, 0.74; 0.73-0.76) individuals. Non-US-born Pacific Islander individuals experienced higher preterm birth rates compared with US-born Pacific Islander individuals (aOR, 1.15; 95% CI, 1.04-1.27). Puerto Rican individuals born in Puerto Rico compared with those born in US states or Washington, DC, also had higher preterm birth rates (aOR, 1.07; 95% CI, 1.03-1.12).

Conclusions and Relevance

Overall preterm birth rates were lower among non-US-born individuals compared with US-born individuals. However, there was substantial heterogeneity in preterm birth rates across maternal racial and ethnic groups, particularly among disaggregated Asian and Hispanic subgroups.

Rural-urban disparities in pregestational and gestational diabetes in pregnancy: Serial, cross-sectional analysis of over 12 million pregnancies

OBJECTIVE

To compare trends in pregestational (DM) and gestational diabetes (GDM) in pregnancy in rural and urban areas in the USA, because pregnant women living in rural areas face unique challenges that contribute to rural-urban disparities in adverse pregnancy outcomes.

DESIGN

Serial, cross-sectional analysis.

SETTING

US National Center for Health Statistics (NCHS) Natality Files from 2011 to 2019.

POPULATION

A total of 12 401 888 singleton live births to nulliparous women aged 15-44 years.

METHODS

We calculated the frequency (95% confidence interval [CI]) per 1000 live births, the mean annual percentage change (APC), and unadjusted and age-adjusted rate ratios (aRR) of DM and GDM in rural compared with urban maternal residence (reference) per the NCHS Urban-Rural Classification Scheme overall, and by delivery year, reported race and ethnicity, and US region (effect measure modification).

MAIN OUTCOME MEASURES

The outcomes (modelled separately) were diagnoses of DM and GDM.

RESULTS

From 2011 to 2019, there were increases in both the frequency (per 1000 live births; mean APC, 95% CI per year) of DM and GDM in rural areas (DM: 7.6 to 10.4 per 1000 live births; APC 2.8%, 95% CI 2.2%-3.4%; and GDM: 41.4 to 58.7 per 1000 live births; APC 3.1%, 95% CI 2.6%-3.6%) and urban areas (DM: 6.1 to 8.4 per 1000 live births; APC 3.3%, 95% CI 2.2%-4.4%; and GDM: 40.8 to 61.2 per 1000 live births; APC 3.9%, 95% CI 3.3%-4.6%). Individuals living in rural areas were at higher risk of DM (aRR 1.48, 95% CI 1.45%-1.51%) and GDM versus those in urban areas (aRR 1.17, 95% CI 1.16%-1.18%). The increased risk was similar each year for DM (interaction p = 0.8), but widened over time for GDM (interaction p < 0.01). The rural-urban disparity for DM was wider for individuals who identified as Hispanic race/ethnicity and in the South and West (interaction p < 0.01 for all); and for GDM the rural-urban disparity was generally wider for similar factors (i.e. Hispanic race/ethnicity, and in the South; interaction p < 0.05 for all).

CONCLUSIONS

The frequency of DM and GDM increased in both rural and urban areas of the USA from 2011 to 2019 among nulliparous pregnant women. Significant rural-urban disparities existed for DM and GDM, and increased over time for GDM. These rural-urban disparities were generally worse among those of Hispanic race/ethnicity and in women who lived in the South. These findings have implications for delivering equitable diabetes care in pregnancy in rural US communities.

Comparing population-based fetal growth standards in a US cohort

BACKGROUND

No fetal growth standard is currently endorsed for universal use in the United States. Newer standards improve upon the methodologic limitations of older studies; however, before adopting into practice, it is important to know how recent standards perform at identifying fetal undergrowth or overgrowth and at predicting subsequent neonatal morbidity or mortality in US populations.

OBJECTIVE

To compare classification of estimated fetal weight that is <5th or 10th percentile or >90th percentile by 6 population-based fetal growth standards and the ability of these standards to predict a composite of neonatal morbidity and mortality.

STUDY DESIGN

We used data from the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be cohort, which recruited nulliparous women in the first trimester at 8 US clinical centers (2010-2014). Estimated fetal weight was obtained from ultrasounds at 16 to 21 and 22 to 29 weeks of gestation (N=9534 women). We calculated rates of fetal growth restriction (estimated fetal weight <5th and 10th percentiles; fetal growth restriction<5 and fetal growth restriction<10) and estimated fetal weight >90th percentile (estimated fetal weight>90) from 3 large prospective fetal growth cohorts with similar rigorous methodologies: INTERGROWTH-21, World Health Organization-sex-specific and combined, Eunice Kennedy Shriver National Institute of Child Health and Human Development race-ethnic-specific and unified, and the historic Hadlock reference. To determine whether differential classification of fetal growth restriction or estimated fetal weight >90 among standards was clinically meaningful, we then compared area under the curve and sensitivity of each standard to predict small for gestational age or large for gestational age at birth, composite perinatal morbidity and mortality alone, and small for gestational age or large for gestational age with composite perinatal morbidity and mortality.

RESULTS

The standards classified different proportions of fetal growth restriction and estimated fetal weight>90 for ultrasounds at 16 to 21 (visit 2) and 22 to 29 (visit 3) weeks of gestation. At visit 2, the Eunice Kennedy Shriver National Institute of Child Health and Human Development race-ethnic-specific, World Health Organization sex-specific and World Health Organization-combined identified similar rates of fetal growth restriction<10 (8.4%-8.5%) with the other 2 having lower rates, whereas Eunice Kennedy Shriver National Institute of Child Health and Human Development race-ethnic-specific identified the highest rate of fetal growth restriction<5 (5.0%) compared with the other references. At visit 3, World Health Organization sex-specific classified 9.2% of fetuses as fetal growth restriction<10, whereas the other 5 classified a lower proportion as follows: World Health Organization-combined (8.4%), Eunice Kennedy Shriver National Institute of Child Health and Human Development race-ethnic-specific (7.7%), INTERGROWTH (6.2%), Hadlock (6.1%), and Eunice Kennedy Shriver National Institute of Child Health and Human Development unified (5.1%). INTERGROWTH classified the highest (21.3%) as estimated fetal weight>90 whereas Hadlock classified the lowest (8.3%). When predicting composite perinatal morbidity and mortality in the setting of early-onset fetal growth restriction, World Health Organization had the highest area under the curve of 0.53 (95% confidence interval, 0.51-0.53) for fetal growth restriction<10 at 22 to 29 weeks of gestation, but the areas under the curve were similar among standards (0.52). Sensitivity was generally low across standards (22.7%-29.1%). When predicting small for gestational age birthweight with composite neonatal morbidity or mortality, for fetal growth restriction<10 at 22 to 29 weeks of gestation, World Health Organization sex-specific had the highest area under the curve (0.64; 95% confidence interval, 0.60-0.67) and INTERGROWTH had the lowest (area under the curve=0.58; 95% confidence interval 0.55-0.62), though all standards had low sensitivity (7.0%-9.6%).

CONCLUSION

Despite classifying different proportions of fetuses as fetal growth restriction or estimated fetal weight>90, all standards performed similarly in predicting perinatal morbidity and mortality. Classification of different percentages of fetuses as fetal growth restriction or estimated fetal weight>90 among references may have clinical implications in the management of pregnancies, such as increased antenatal monitoring for fetal growth restriction or cesarean delivery for suspected large for gestational age. Our findings highlight the importance of knowing how standards perform in local populations, but more research is needed to determine if any standard performs better at identifying the risk of morbidity or mortality.

Cannabis Exposure and Adverse Pregnancy Outcomes Related to Placental Function

Importance

Cannabis use is increasing among reproductive-age individuals and the risks associated with cannabis exposure during pregnancy remain uncertain.

Objective

To evaluate the association between maternal cannabis use and adverse pregnancy outcomes known to be related to placental function.

Design, Setting, and Participants

Ancillary analysis of nulliparous individuals treated at 8 US medical centers with stored urine samples and abstracted pregnancy outcome data available. Participants in the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be cohort were recruited from 2010 through 2013; the drug assays and analyses for this ancillary project were completed from June 2020 through April 2023.

Exposure

Cannabis exposure was ascertained by urine immunoassay for 11-nor-9-carboxy-Δ9-tetrahydrocannabinol using frozen stored urine samples from study visits during the pregnancy gestational age windows of 6 weeks and 0 days to 13 weeks and 6 days (visit 1); 16 weeks and 0 days to 21 weeks and 6 days (visit 2); and 22 weeks and 0 days to 29 weeks and 6 days (visit 3). Positive results were confirmed with liquid chromatography tandem mass spectrometry. The timing of cannabis exposure was defined as only during the first trimester or ongoing exposure beyond the first trimester.

Main Outcome and Measure

The dichotomous primary composite outcome included small-for-gestational-age birth, medically indicated preterm birth, stillbirth, or hypertensive disorders of pregnancy ascertained by medical record abstraction by trained perinatal research staff with adjudication of outcomes by site investigators.

Results

Of 10 038 participants, 9257 were eligible for this analysis. Of the 610 participants (6.6%) with cannabis use, 32.4% (n = 197) had cannabis exposure only during the first trimester and 67.6% (n = 413) had ongoing exposure beyond the first trimester. Cannabis exposure was associated with the primary composite outcome (25.9% in the cannabis exposure group vs 17.4% in the no exposure group; adjusted relative risk, 1.27 [95% CI, 1.07-1.49]) in the propensity score-weighted analyses after adjustment for sociodemographic characteristics, body mass index, medical comorbidities, and active nicotine use ascertained via urine cotinine assays. In a 3-category cannabis exposure model (no exposure, exposure only during the first trimester, or ongoing exposure), cannabis use during the first trimester only was not associated with the primary composite outcome; however, ongoing cannabis use was associated with the primary composite outcome (adjusted relative risk, 1.32 [95% CI, 1.09-1.60]).

Conclusions and Relevance

In this multicenter cohort, maternal cannabis use ascertained by biological sampling was associated with adverse pregnancy outcomes related to placental dysfunction.

Cardiovascular Health in the Postpartum Period

This article in the Women’s Health series discusses recent increases in US maternal death rates, disparities in rates by race and ethnicity, poor cardiovascular health (CVH) as one of the multifactorial causes, and clinical approaches to assessing and treating poor CVH postpartum.

US County-Level Variation in Preterm Birth Rates, 2007-2019

Importance

Preterm birth is a leading cause of preventable neonatal morbidity and mortality. Preterm birth rates at the national level may mask important geographic variation in rates and trends at the county level.

Objective

To estimate age-standardized preterm birth rates by US county from 2007 to 2019.

Design, Setting, and Participants

This serial cross-sectional study used data from the National Center for Health Statistics composed of all live births in the US between 2007 and 2019. Data analyses were performed between March 22, 2022, and September 29, 2022.

Main Outcomes and Measures

Age-standardized preterm birth (<37 weeks' gestation) and secondarily early preterm birth (<34 weeks' gestation) rates by county and year calculated with a validated small area estimation model (hierarchical bayesian spatiotemporal model) and percent change in preterm birth rates using log-linear regression models.

Results

Between 2007 and 2019, there were 51 044 482 live births in 2383 counties. In 2007, the national age-standardized preterm birth rate was 12.6 (95% CI, 12.6-12.7) per 100 live births. Preterm birth rates varied significantly among counties, with an absolute difference between the 90th and 10th percentile counties of 6.4 (95% CI, 6.2-6.7). The gap between the highest and lowest counties for preterm births was 20.7 per 100 live births in 2007. Several counties in the Southeast consistently had the highest preterm birth rates compared with counties in California and New England, which had the lowest preterm birth rates. Although there was no statistically significant change in preterm birth rates between 2007 and 2019 at the national level (percent change, -5.0%; 95% CI, -10.7% to 0.9%), increases occurred in 15.4% (95% CI, 14.1%-16.9%) of counties. The absolute and relative geographic inequalities were similar across all maternal age groups. Higher quartile of the Social Vulnerability Index was associated with higher preterm birth rates (quartile 4 vs quartile 1 risk ratio, 1.34; 95% CI, 1.31-1.36), which persisted across the study period. Similar patterns were observed for early preterm birth rates.

Conclusions and Relevance

In this serial cross-sectional study of county-level preterm and early preterm birth rates, substantial geographic disparities were observed, which were associated with place-based social disadvantage. Stability in aggregated rates of preterm birth at the national level masked increases in nearly 1 in 6 counties between 2007 and 2019.

Racial and ethnic differences in the association between pregnancy dysglycemia and cardiometabolic risk factors 10-14 years' postpartum in the HAPO follow-up study

Associations between pregnancy dysglycemia and subsequent maternal cardiometabolic factors 10-14 years postpartum were largely similar across self-identified racial and ethnic groups among birthing people in the U.S. enrolled in the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) Follow-up Study.

Labour agentry and subsequent adverse mental health outcomes: A follow-up study of the ARRIVE Trial

OBJECTIVE

Labour can be traumatic for women who perceive they are not involved in decisions affecting their care during labour. Our objective was to assess the relation between labour agentry and subsequent mental health.

DESIGN

Follow-up cohort study.

SETTING

U.S. Tertiary care center.

POPULATION

Participants from Utah who participated in the ARRIVE (A Randomized Trial of Induction Versus Expectant Management) trial.

METHODS

During the ARRIVE trial, participants completed the Labor Agentry Scale twice, a validated questionnaire measuring perceived control of patients during childbirth. ARRIVE participants from Utah subsequently were asked to complete questions about mental health history and stressful events occurring since the trial, as well as surveys including the Primary Care Posttraumatic Stress Disorder (PC-PTSD) screen, Edinburgh Postnatal Depression Scale (EPDS) and Generalised Anxiety Disorder-7 (GAD-7) screen. The lower quartile of both agentry measurements defined a person's ordinal agentry category, used for assessing cohort characteristics by exposure category. Continuous minimum agentry was included in adjusted modelling.

MAIN OUTCOME MEASURES

The primary outcome was a mental health composite including a positive screen for depression, anxiety, or PTSD or self-report of a diagnosis or exacerbation since their delivery.

RESULTS

In all, 766 of 1042 (74%) people responded to the survey (median 4.4, range 2.5-6.4 years after delivery) and 753 had complete data for analysis. In unadjusted comparisons across ordinal agentry category, lower agentry was significantly associated with the primary composite endpoint, and depressive symptoms (test of trend p = 0.003 primary, p = 0.004 depression). Lower labour agentry scores were associated with incremental odds of the primary endpoint (1 SD [24 units], adjusted odds ratio [aOR] 1.21, 95% CI 1.41-1.03), driven by depressive symptoms or self-reported diagnosis (aOR 1.25, 95% CI 1.47-1.05).

CONCLUSIONS

Lower labour agentry at the time of birth was associated with a greater risk for mental health conditions years after delivery, indicating a potential opportunity for primary prevention of subsequent depression.

Promoting REproductive Planning And REadiness in Diabetes (PREPARED) Study protocol: a clinic-randomised controlled trial testing a technology-based strategy to promote preconception care for women with type 2 diabetes

INTRODUCTION

Women with type 2 diabetes (T2DM) are more likely to experience adverse reproductive outcomes, yet preconception care can significantly reduce these risks. For women with T2DM, preconception care includes reproductive planning and patient education on: (1) the importance of achieving glycaemic control before pregnancy, (2) using effective contraception until pregnancy is desired, (3) discontinuing teratogenic medications if pregnancy could occur, (4) taking folic acid, and (5) managing cardiovascular and other risks. Despite its importance, few women with T2DM receive recommended preconception care.

METHODS AND ANALYSIS

We are conducting a two-arm, clinic-randomised trial at 51 primary care practices in Chicago, Illinois to evaluate a technology-based strategy to 'hardwire' preconception care for women of reproductive age with T2DM (the PREPARED (Promoting REproductive Planning And REadiness in Diabetes) strategy) versus usual care. PREPARED leverages electronic health record (EHR) technology before and during primary care visits to: (1) promote medication safety, (2) prompt preconception counselling and reproductive planning, and (3) deliver patient-friendly educational tools to reinforce counselling. Post-visit, text messaging is used to: (4) encourage healthy lifestyle behaviours. English and Spanish-speaking women, aged 18-44 years, with T2DM will be enrolled (N=840; n=420 per arm) and will receive either PREPARED or usual care based on their clinic's assignment. Data will be collected from patient interviews and the EHR. Outcomes include haemoglobin A1c (primary), reproductive knowledge and self-management behaviours. We will use generalised linear mixed-effects models (GLMMs) to evaluate the impact of PREPARED on these outcomes. GLMMs will include a fixed effect for treatment assignment (PREPARED vs usual care) and random clinic effects.

ETHICS AND DISSEMINATION

This study was approved by the Northwestern University Institutional Review Board (STU00214604). Study results will be published in journals with summaries shared online and with participants upon request.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT04976881).

Neighborhood Socioeconomic Disadvantage and Abnormal Birth Weight

OBJECTIVE

To examine whether exposure to community or neighborhood socioeconomic disadvantage as measured by the ADI (Area Deprivation Index) is associated with risk of abnormal birth weight among nulliparous individuals with singleton gestations.

METHODS

This was a secondary analysis from the prospective cohort NuMoM2b study (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-To-Be). Participant addresses at cohort enrollment between 6 and 13 weeks of gestation were geocoded at the Census tract level and linked to the 2015 ADI. The ADI, which incorporates the domains of income, education, employment, and housing quality into a composite national ranking of neighborhood socioeconomic disadvantage, was categorized by quartiles (quartile 1, least disadvantaged, reference; quartile 4, most disadvantaged). Outcomes were large for gestational age (LGA; birth weight at or above the 90th percentile) and small for gestational age (SGA; birth weight below the 10th percentile) compared with appropriate for gestational age (AGA; birth weight 10th-90th percentile) as determined with the 2017 U.S. natality reference data, standardized for fetal sex. Multinomial logistic regression models were adjusted for potential confounding variables.

RESULTS

Of 8,983 assessed deliveries in the analytic population, 12.7% (n=1,143) were SGA, 8.2% (n=738) were LGA, and 79.1% (n=7,102) were AGA. Pregnant individuals living in the highest ADI quartile (quartile 4, 17.8%) had an increased odds of delivering an SGA neonate compared with those in the lowest referent quartile (quartile 1, 12.4%) (adjusted odds ratio [aOR] 1.32, 95% CI 1.09-1.55). Pregnant individuals living in higher ADI quartiles (quartile 2, 10.3%; quartile 3, 10.7%; quartile 4, 9.2%) had an increased odds of delivering an LGA neonate compared with those in the lowest referent quartile (quartile 1, 8.2%) (aOR: quartile 2, 1.40, 95% CI 1.19-1.61; quartile 3, 1.35, 95% CI 1.09-1.61; quartile 4, 1.47, 95% CI 1.20-1.74).

CONCLUSION

Neonates of nulliparous pregnant individuals living in U.S. neighborhoods with higher area deprivation were more likely to have abnormal birth weights at both extremes.

Sodium intake and the development of hypertensive disorders of pregnancy

BACKGROUND

In nonpregnant populations, sodium intake has been associated with the development of chronic hypertension, and sodium restriction has been identified as a strategy to reduce blood pressure. Data regarding the relationship between sodium intake and the development of hypertensive disorders of pregnancy are limited and conflicting.

OBJECTIVE

This study aimed to assess the association between daily periconceptional sodium intake and the risk of hypertensive disorders of pregnancy.

STUDY DESIGN

This was a secondary analysis of the prospective Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-To-Be study. Individuals with nonanomalous, singleton pregnancies who completed food frequency questionnaires with recorded sodium intake in the 3 months before pregnancy were included in the analysis. Individuals whose pregnancies did not progress beyond 20 weeks of gestation were excluded from the analysis. Sodium intake was categorized as low (<2 g per day), medium (2 to <3 g per day), or high (≥3 g per day), based on thresholds used in the nonpregnant population. The primary outcome was the development of a new-onset hypertensive disorder of pregnancy, including gestational hypertension; preeclampsia; hemolysis, elevated liver enzymes, and low platelet count syndrome; superimposed preeclampsia; or eclampsia. Bivariable analyses were performed using Kruskal-Wallis and chi-square tests. Poisson regression was used to estimate adjusted incidence risk ratios with 95% confidence intervals after controlling for potentially confounding factors.

RESULTS

Among 7458 individuals included in this analysis, 2336 (31%) reported low sodium intake, 2792 (37%) reported medium sodium intake, and 2330 (31%) reported high sodium intake. Individuals with high sodium intake were more likely to have chronic hypertension, to use tobacco, and to be living with obesity. The risk of developing a hypertensive disorder of pregnancy was similar among groups (medium vs low adjusted incidence risk ratio: 1.10 [95% confidence interval, 0.94-1.28]; high vs low adjusted incidence risk ratio: 1.17 [95% confidence interval, 1.00-1.37]). There was no difference in neonatal outcomes by sodium intake, including preterm birth, small-for-gestational-age neonate, and admission to the neonatal intensive care unit.

CONCLUSION

Sodium intake was not associated with the risk of developing a hypertensive disorder of pregnancy. This lack of association contrasts with that between sodium intake and hypertension in the nonpregnant state and may reflect differences in the pathophysiology underlying pregnancy- vs non-pregnancy-related hypertensive disorders.

Body Mass Index, Adverse Pregnancy Outcomes, and Cardiovascular Disease Risk

BACKGROUND

Obesity is a well-established risk factor for both adverse pregnancy outcomes (APOs) and cardiovascular disease (CVD). However, it is not known whether APOs are mediators or markers of the obesity-CVD relationship. This study examined the association between body mass index, APOs, and postpartum CVD risk factors.

METHODS

The sample included adults from the nuMoM2b (Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-To-Be) Heart Health Study who were enrolled in their first trimester (6 weeks-13 weeks 6 days gestation) from 8 United States sites. Participants had a follow-up visit at 3.7 years postpartum. APOs, which included hypertensive disorders of pregnancy, preterm birth, small-for-gestational-age birth, and gestational diabetes, were centrally adjudicated. Mediation analyses estimated the association between early pregnancy body mass index and postpartum CVD risk factors (hypertension, hyperlipidemia, and diabetes) and the proportion mediated by each APO adjusted for demographics and baseline health behaviors, psychosocial stressors, and CVD risk factor levels.

RESULTS

Among 4216 participants enrolled, mean±SD maternal age was 27±6 years. Early pregnancy prevalence of overweight was 25%, and obesity was 22%. Hypertensive disorders of pregnancy occurred in 15%, preterm birth in 8%, small-for-gestational-age birth in 11%, and gestational diabetes in 4%. Early pregnancy obesity, compared with normal body mass index, was associated with significantly higher incidence of postpartum hypertension (adjusted odds ratio, 1.14 [95% CI, 1.10-1.18]), hyperlipidemia (1.11 [95% CI, 1.08-1.14]), and diabetes (1.03 [95% CI, 1.01-1.04]) even after adjustment for baseline CVD risk factor levels. APOs were associated with higher incidence of postpartum hypertension (1.97 [95% CI, 1.61-2.40]) and hyperlipidemia (1.31 [95% CI, 1.03-1.67]). Hypertensive disorders of pregnancy mediated a small proportion of the association between obesity and incident hypertension (13% [11%-15%]) and did not mediate associations with incident hyperlipidemia or diabetes. There was no significant mediation by preterm birth or small-for-gestational-age birth.

CONCLUSIONS

There was heterogeneity across APO subtypes in their association with postpartum CVD risk factors and mediation of the association between early pregnancy obesity and postpartum CVD risk factors. However, only a small or nonsignificant proportion of the association between obesity and CVD risk factors was mediated by any of the APOs, suggesting APOs are a marker of prepregnancy CVD risk and not a predominant cause of postpartum CVD risk.

Searching and visualizing genetic associations of pregnancy traits by using GnuMoM2b

Adverse pregnancy outcomes (APOs) are major risk factors for women's health during pregnancy and even in the years after pregnancy. Due to the heterogeneity of APOs, only few genetic associations have been identified. In this report, we conducted genome-wide association studies (GWASs) of 479 traits that are possibly related to APOs using a large and racially diverse study, Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be (nuMoM2b). To display extensive results, we developed a web-based tool GnuMoM2b (https://gnumom2b.cumcobgyn.org/) for searching, visualizing, and sharing results from a GWAS of 479 pregnancy traits as well as phenome-wide association studies of more than 17 million single nucleotide polymorphisms. The genetic results from 3 ancestries (Europeans, Africans, and Admixed Americans) and meta-analyses are populated in GnuMoM2b. In conclusion, GnuMoM2b is a valuable resource for extraction of pregnancy-related genetic results and shows the potential to facilitate meaningful discoveries.

Risk factors and perinatal outcomes for persistent placenta previa in nulliparas

BACKGROUND

Placenta previa diagnosed on midtrimester ultrasound often resolves by the third trimester. Multiparity and previous cesarean delivery have been associated with persistence of placenta previa at delivery. Risk factors for persistent placenta previa in nulliparas are not well characterized.

OBJECTIVE

This study aimed to identify risk factors for persistent placenta previa in the nulliparous population, and evaluate differences in outcomes between persistent and resolved placenta previa.

STUDY DESIGN

This was a secondary analysis of the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be (nuMoM2b), a prospective cohort study that observed 10,037 nulliparous individuals throughout pregnancy. Nulliparas diagnosed with placenta previa on midtrimester ultrasound were included in this analysis. Baseline characteristics and delivery outcomes of nulliparas with persistent placenta previa were compared with those of nulliparas with resolved placenta previa. Multivariate logistic regression with stepwise model selection was used for adjusted analyses.

RESULTS

A total of 171 nulliparas (1.7%) in the nuMoM2b study were diagnosed with placenta previa on midtrimester ultrasound, of whom 17% (n=29) had persistent placenta previa at delivery. When compared with those with resolved placenta previa, nulliparas with persistent placenta previa were more likely to be older (median, 32 years [interquartile range, 30-37] vs 29 years [interquartile range, 25-31]; P<.01), have a previous pregnancy of <20 weeks (48.3% vs 22.5%; P=.01), have a previous dilation and curettage/evacuation procedure (27.6% vs 10.6%; P=.03), or have a pregnancy that resulted from assisted reproductive technology (31% vs 4.9%; P=.01). After adjusting for potential confounders, maternal age (adjusted odds ratio, 1.11; 95% confidence interval, 1.02-1.21), in vitro fertilization (adjusted odds ratio, 9.00; 95% confidence interval, 1.97-41.14), and previous pregnancy of <20 weeks (adjusted odds ratio, 2.77; 95% confidence interval, 1.10-6.95) remained statistically significant risk factors for persistent placenta previa. Persistent placenta previa was also associated with higher likelihood of antepartum admission (10.3% vs 0%; P<.01), preterm delivery (34.5% vs 12%; P<.01), lower neonatal birthweight (median, 2847 g [interquartile range, 2655-3310] vs 3263 g [interquartile range, 2855-3560]), and cesarean delivery (100% vs 20.4%; P<.001), but there were no differences in overall pregnancy or neonatal outcomes.

CONCLUSION

In nulliparous individuals diagnosed with placenta previa on midtrimester ultrasound, older maternal age, previous pregnancy of <20 weeks, and in vitro fertilization are associated with persistent placenta previa at delivery.

Association between glycemic control and group B streptococcus colonization among pregnant individuals with pregestational diabetes

PROBLEM

Pregestational diabetes increases the risk of group B streptococcus (GBS) colonization in pregnancy. Whether glycemic control is associated with differences in this risk is unknown. We examined the association between glycemic control and GBS colonization among pregnant individuals with pregestational diabetes.

METHOD OF STUDY

A retrospective cohort of pregnant individuals with pregestational diabetes at a tertiary care center. The exposure was glycemic control, measured as hemoglobin A1c (A1c) at >20 weeks and assessed categorically at thresholds of <6.5% and <6.0%, and secondarily, as a continuous percentage. The outcome was maternal GBS colonization. Multivariable logistic regression was used and adjusted for age, parity, race, and ethnicity as a social determinant, body mass index, type of diabetes, and gestational age at A1c assessment.

RESULTS

Among 305 individuals (33% Type 1, 67% type 2), 45.0% (n = 140) were colonized with GBS. Individuals with an A1c < 6.5% were half as likely to be colonized with GBS compared with those with a A1c ≥ 6.5% (38.8% vs. 53.9%; adjusted odds ratio, AOR: 0.55; 95% CI: 0.33-0.91). Results were unchanged at an A1c threshold of <6.0% (35.7% vs. 48.5%; AOR: 0.60; 95% CI: 0.36-0.98). Individuals with a higher A1c as a continuous measure (%) were more likely to be colonized (AOR: 1.57 per 1%; 95% CI: 1.25-1.97).

CONCLUSIONS

Pregnant individuals with pregestational diabetes with worse glycemic control were at an increased risk of GBS colonization. Further study is needed to understand if improved glycemic control leads to lower risk of GBS colonization.

Adverse Pregnancy Outcomes and Future Metabolic Syndrome

Background: Metabolic syndrome (MetS) is associated with a history of gestational diabetes (GDM), hypertensive disorders of pregnancy (HDP), and preterm birth (PTB), but it is unclear whether this association is due to the pregnancy complication(s) or prepregnancy/early pregnancy confounders. The study examines the association of GDM, HDP, and PTB with MetS 2-7 years later, independent of early pregnancy factors. Materials and Methods: Large, diverse cohort of nulliparous pregnant people with singleton gestations enrolled during their first trimester and who attended a follow-up study visit 2-7 years after delivery. The longitudinal cohort was recruited from eight medical centers across the United States. Using standardized protocols, anthropometry, biospecimens, and surveys were collected at study visits and pregnancy outcomes were abstracted from medical records. We estimated the relative risk of prevalent MetS at the follow-up study visit for participants with GDM, HDP, or PTB (vs. no complications), adjusting for early pregnancy age, body mass index, self-reported race/ethnicity, insurance type, and smoking status. Results: Of 4,402 participants, 738 (16.8%) had MetS at follow-up: 13.1% (441/3,365) among those with no complications, and 27.9% (290/1,002) among those with complications. MetS occurred in 39.0% of GDM (73/187, adjusted relative risk [aRR] = 1.75; 95% confidence interval [CI] 1.42-2.16); 29.2% of HDP (176/603, aRR = 1.49; 95% CI 1.27-1.75); and 29.7% of PTB (113/380, aRR = 1.78; 95% CI 1.49-2.12). Those who had both HDP and PTB (n = 113) had an aRR = 1.95 (95% CI 1.50-2.54). Conclusions: People whose pregnancies were complicated by GDM, HDP, or PTB are at a higher risk of MetS within 2-7 years after delivery, independent of early pregnancy risk factors. The highest MetS risk follows pregnancies complicated by both HDP and PTB.

Association Between Prenatal Diagnosis and Age at Surgery for Noncritical and Critical Congenital Heart Defects

BACKGROUND

The relationship between the prenatal diagnosis of congenital heart defects (CHDs) and age at CHD surgery is poorly understood, despite the known relationships between age at surgery and long-term outcomes. The objective of this study was to determine the associations between prenatal diagnosis of CHD and age at surgery, and whether these associations differ for critical and noncritical CHDs.

METHODS

This is a cohort analysis of patients aged 0 to 9 years who received their initial cardiac surgery at Ann & Robert H. Lurie Children's Hospital of Chicago between 2015 and 2021 with prenatal diagnosis as the exposure variable. All data were obtained from the locally maintained Society of Thoracic Surgeons Congenital Heart Surgery Database at Lurie Children's Hospital. We used multivariable fixed effects regression models to estimate the strength of the association of prenatal diagnosis with age at surgery among patients with critical (surgery ≤60 days) and noncritical (surgery >60 days) CHDs.

RESULTS

Of 1131 individuals who met inclusion criteria, 532 (47%) had a prenatal diagnosis, 428 (38%) had critical CHDs, 533 (47%) were female, and the median age at surgery was 119 days (interquartile range, 11-309 days). After controlling for demographics, comorbidities, and surgical complexity, the mean age at surgery was significantly younger in those with prenatally versus postnatally diagnosed critical CHD (7.1 days sooner, P<0.001) and noncritical CHDs (atrial septal defects [12.4 months sooner, P=0.037], ventricular septal defects [6.0 months sooner, P<0.003], and noncritical coarctation of the aorta [1.8 months sooner, P=0.010]).

CONCLUSIONS

Younger age at CHD surgery, which is associated with postsurgical neurodevelopmental and physical outcomes, is significantly associated with prenatal CHD diagnosis. This relationship was identified for both critical and noncritical CHDs.

Association of maternal body mass index with success and outcomes of attempted operative vaginal delivery

BACKGROUND

Increasing maternal body mass index is associated with increased morbidity at cesarean delivery in a dose-dependent manner. In some clinical scenarios, operative vaginal delivery is a strategy to prevent the morbidity associated with second-stage cesarean delivery, but the relationship between maternal body mass index and outcomes of attempted operative vaginal delivery is not well characterized.

OBJECTIVE

This study aimed to assess whether the success of and adverse outcomes after attempted operative vaginal delivery are associated with maternal body mass index at delivery among nulliparous individuals.

STUDY DESIGN

This was a secondary analysis from the prospective cohort Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-To-Be study. This analysis included cephalic live-born nonanomalous singleton pregnancies ≥34 weeks at delivery with an attempted operative vaginal delivery (either forceps or vacuum). The primary exposure was maternal body mass index at delivery (≥30 vs <30 kg/m2 [referent]). The primary outcome was an unsuccessful operative vaginal delivery attempt, defined as a cesarean delivery after an attempted operative vaginal delivery. The secondary outcomes included maternal and neonatal adverse outcomes. Multivariable logistic regression was used, and statistical interaction between operative instrument type (vacuum vs forceps) and body mass index was assessed.

RESULTS

Of 10,038 assessed individuals, 791 (7.9%) had an attempted operative vaginal delivery and were included in this analysis. Of note, 325 individuals (41%) had a body mass index ≥30 kg/m2 at delivery. Overall, 42 of 791 participants (5%) experienced an unsuccessful operative vaginal delivery. Individuals with a body mass index ≥30 kg/m2 at delivery were more than twice as likely to have an unsuccessful operative vaginal delivery than those with a body mass index <30 kg/m2 (8.0% vs 3.4%; adjusted odds ratio, 2.23; 95% confidence interval, 1.16-4.28; P=.005). Composite maternal morbidity and composite neonatal morbidity did not vary by body mass index group. There was no evidence of interaction or effect modification by operative instrument type for the rate of unsuccessful operative vaginal delivery attempt, composite maternal morbidity, or composite neonatal morbidity.

CONCLUSION

Among nulliparous individuals who underwent an attempted operative vaginal delivery, those with a body mass index ≥30 kg/m2 at delivery were more likely to have an unsuccessful operative vaginal delivery attempt than those with a body mass index <30 kg/m2. There was no difference in composite maternal or neonatal morbidity after attempted operative vaginal delivery by body mass index category.

Risk Factors for Perinatal Transmission of Hepatitis C Virus

OBJECTIVE

To estimate the rate of perinatal transmission of hepatitis C virus (HCV) infection, to identify risk factors for perinatal transmission of HCV infection, and to determine the viremic threshold for perinatal transmission.

METHODS

This was a prospective, multicenter, observational study of pregnant individuals at less than 24 weeks of gestation screened for HCV infection from 2012 to 2018 in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Maternal-Fetal Medicine Units Network. Individuals found to be HCV antibody-positive were followed throughout pregnancy. Children were followed for evidence of perinatal transmission at 2-6 months (HCV RNA testing) and at 18-24 months (HCV RNA and antibody testing) of life. The primary outcome was perinatal transmission, defined as positive test results at either follow-up time point.

RESULTS

A total of 109,379 individuals were screened for HCV infection. Of the 1,224 participants who screened positive, 772 (63.1%) enrolled and 432 of those 772 (56.0%) had data available to assess primary outcome. The overall rate of perinatal transmission was 6.0% (26/432, 95% CI 4.0-8.7%). All children with HCV infection were born to individuals with demonstrable viremia. In viremic participants (n=314), the perinatal transmission rate was 8.0% (95% CI 5.2-11.5%). Risk factors for perinatal transmission included HCV RNA greater than 106 international units/mL (adjusted odds ratio [aOR] 8.22, 95% CI 3.16-21.4) and vaginal bleeding reported at any time before delivery (aOR 3.26, 95% CI 1.32-8.03). A viremic threshold for perinatal transmission could not be established.

CONCLUSION

Perinatal transmission of HCV infection was limited to viremic individuals. High viral loads and antepartum bleeding were associated with perinatal transmission.

The association between multidimensional sleep health and gestational weight gain

BACKGROUND

Although poor sleep health is associated with weight gain and obesity in the non-pregnant population, research on the impact of sleep health on weight change among pregnant people using a multidimensional sleep health framework is needed.

OBJECTIVES

This secondary data analysis of the Nulliparous Pregnancy Outcome Study: Monitoring Mothers-to-be Sleep Duration and Continuity Study (n = 745) examined associations between mid-pregnancy sleep health indicators, multidimensional sleep health and gestational weight gain (GWG).

METHODS

Sleep domains (i.e. regularity, nap duration, timing, efficiency and duration) were assessed via actigraphy between 16 and 21 weeks of gestation. We defined 'healthy' sleep in each domain with empirical thresholds. Multidimensional sleep health was based on sleep profiles derived from latent class analysis and composite score defined as the sum of healthy sleep domains. Total GWG, the difference between self-reported pre-pregnancy weight and the last measured weight before delivery, was converted to z-scores using gestational age- and BMI-specific charts. GWG was defined as low (<-1 SD), moderate (-1 or +1 SD) and high (>+1 SD).

RESULTS

Nearly 50% of the participants had a healthy sleep profile (i.e. healthy sleep in most domains), whereas others had a sleep profile defined as having varying degrees of unhealthy sleep in each domain. The individual sleep domains were associated with a 20%-30% lower risk of low or high GWG. Each additional healthy sleep indicator was associated with a 10% lower risk of low (vs. moderate), but not high, GWG. Participants with late timing, long duration and low efficiency (vs. healthy) profiles had the strongest risk of low GWG (relative risk 1.5, 95% confidence interval 0.9, 2.4). Probabilistic bias analysis suggested that most associations between individual sleep health indicators, sleep health profiles and GWG were biased towards the null.

CONCLUSIONS

Future research should determine whether sleep health is an intervention target for healthy GWG.