US Birth Research Articles

The relationship between obstetrical interventions and the increase in U.S. preterm births, 2014-2019.

We examined the relationship between obstetrical intervention and preterm birth in the United States between 2014 and 2019. This observational study analyzed 2014–2019 US birth data to assess changes in preterm birth, cesarean delivery, induction of labor, and associated risks. Logistic regression modeled the odds of preterm obstetrical intervention (no labor cesarean or induction) after risk adjustment. The percentage of singleton preterm births in the United States increased by 9.4% from 2014–2019. The percent of singleton, preterm births delivered by cesarean increased by 6.0%, while the percent with induction of labor increased by 39.1%. The percentage of singleton preterm births where obstetrical intervention (no labor cesarean or induction) potentially impacted the gestational age at delivery increased from 47.6% in 2014 to 54.9% in 2019. Preterm interventions were 13% more likely overall in 2019 compared to 2014 and 17% more likely among late preterm births, after controlling for demographic and medical risk factors. Compared to non-Hispanic White women, Non-Hispanic Black women had a higher risk of preterm obstetric interventions. Preterm infants have higher morbidity and mortality rates than term infants, thus any increase in the preterm birth rate is concerning. A renewed effort to understand the trends in preterm interventions is needed to ensure that obstetrical interventions are evidence-based and are limited to those cases where they optimize outcomes for both mothers and babies.

The impact of the Antenatal Late Preterm Steroids trial on the administration of antenatal corticosteroids

In 2016 the Antenatal Late Preterm Steroids study was published, demonstrating that antenatal corticosteroid therapy given to women at risk of late preterm delivery reduces respiratory morbidity in infants. However, the administration of antenatal corticosteroid therapy in late-preterm infants remains controversial. Late-preterm infants do not suffer from the same rates of morbidity as early-preterm infants, and the short-term benefits of antenatal corticosteroid therapy are less pronounced; consequently, the risk of possible harm is more difficult to balance. This study aimed to evaluate the association between the publication of the Antenatal Late Preterm Steroids study or the subsequent changes in guidelines and the rates of antenatal corticosteroid therapy administration in late-preterm infants in the United States. Data analyzed were publicly available US birth certificate data from January 1, 2016 to December 31, 2018. An interrupted time series design was used to analyze the association between publication of the Antenatal Late Preterm Steroids study and changes in monthly rates of antenatal corticosteroid administration in late preterm gestation (34+0 to 36+6 weeks). Births at 28+0 to 31+6 weeks' gestation were used as a control. Antenatal corticosteroid therapy administration in women with births at 32+0 to 34+6 weeks was explored to analyze whether the intervention influenced antenatal corticosteroid therapy administration in women in the subgroup approaching 34 weeks' gestation. Antenatal corticosteroid therapy administration in women with term births (>37 weeks' gestation) was analyzed to explore if the intervention influenced the number of term babies exposed to antenatal corticosteroid therapy. Our regression model allowed analysis of both step and slope changes. February 2016 was chosen as the intervention period. Our sample size was 18,031,950 total births. Of these, 1,056,047 were births at 34+0 to 36+6 weeks' gestation, 123,788 at 28+0 to 31+6 weeks, 153,708 at 32 to 33 weeks, and 16,602,699 were term births. There were 95,708 births at <28 weeks' gestation. There was a statistically significant increase in antenatal corticosteroid therapy administration rates in late preterm births following the online publication of the Antenatal Late Preterm Steroids study (adjusted incidence rate ratio, 1.48; 95% confidence interval, 1.36-1.61; P=.00). A significant increase in antenatal corticosteroid therapy administration rates was also seen in full-term births following the online publication of the Antenatal Late Preterm Steroids study. No significant changes were seen in antenatal corticosteroid administration rates in gestational age groups of 32+0 to 33+6 weeks or 28+0 to 31+6 weeks. Online publication of the Antenatal Late Preterm Steroids study was associated with an immediate and sustained increase in the rates of antenatal corticosteroid therapy administration in late preterm births across the United States, demonstrating a swift and successful implementation of the Antenatal Late Preterm Steroids study guidance into clinical practice. However, there is an unnecessary increase in full-term infants receiving antenatal corticosteroid therapy. Given that the long-term consequences of antenatal corticosteroid therapy are yet to be elucidated, efforts should be made to minimize the number of infants unnecessarily exposed to antenatal corticosteroid therapy.

A Qualitative Study of US Women's Perspectives on Confidence for Physiologic Birth in the Birth Center Model of Prenatal Care.

The purpose of this study was to increase understanding of the components of the US birth center model of prenatal care and how the birth center prenatal care model contributes to birthing people's confidence for physiologic childbirth. This was a qualitative descriptive study using semistructured interviews with individuals who gave birth in freestanding birth centers. Birthing people were recruited from freestanding birth centers in a Midwestern US state and were between the ages of 18 and 42, were English-speaking, and had experienced a birth center birth within the previous 6 months. Interviews were transcribed and analyzed using Glaser's constant comparative method. Twelve women who gave birth in birth centers, representing urban and rural settings, participated. Four core categories were identified encompassing the components of birth center prenatal care and how the birth center model contributes to women's confidence for physiologic birth: birth center culture and processes, midwifery model of care within the birth center, internal influences, and outside influences. Women who gave birth in birth centers believed that the birth center culture and environment, the midwifery model of care in the birth center, internal influences including the belief that birth is a normal physiologic process, and outside influences including family support and positive birth stories contributed to their confidence for physiologic birth.

PM2.5 exposure during pregnancy is associated with altered placental expression of lipid metabolic genes in a US birth cohort

Inhalation of ambient PM2.5, shown to be able to cross the placenta, has been linked to adverse obstetric and postnatal metabolic health outcomes. The placenta regulates fetal growth and influences postnatal development via fetal programming. Placental gene expression may be influenced by intrauterine exposures to PM2.5. Herein, we explore whether maternal PM2.5 exposure during pregnancy alters placental gene expression related to lipid and glucose metabolism in a U.S. birth cohort, the Rhode Island Child Health Study (RICHS). Average PM2.5 exposure level was estimated linking residential addresses and satellite data across the three trimesters using spatio-temporal models. Based on Gene Ontology annotations, we curated a list of 657 lipid and glucose metabolism genes. We conducted a two-staged analysis by leveraging placental RNA-Seq data from 148 subjects to identify top dysregulated metabolic genes associated with PM2.5 (Phase I) and then validated the results in placental samples from 415 participants of the cohort using RT-qPCR (Phase II). Associations between PM2.5 and placental gene expression were explored using multivariable linear regression models in the overall population and in sex-stratified analyses. The average level of PM2.5 exposure across pregnancy was 8.0μg/m3, which is below the national standard of 12μg/m3. Phase I revealed that expression levels of 32 out of the curated list of 657 genes were significantly associated with PM2.5 exposure (FDR P<0.01), 28 genes showed differential expression modified by sex of the infant. Five of these genes (ABHD3, ATP11A, CLTCL1, ST6GALNAC4 and PSCA) were validated using RT-qPCR. Associations were stronger in placentas from male births compared to females, indicating a sex-dependent effect. These genes are involved in inflammation, lipid transport, cell-cell communication or cell invasion. Our results suggest that gestational PM2.5 exposure may alter placental metabolic function. However, whether it confers long-term programming effects postnatally, especially in a sex-specific matter, warrants further studies.

Arginase 1 Deficiency: using genetic databases as a tool to establish global prevalence

Background/objectiveArginase 1 Deficiency (ARG1-D) is a rare inherited metabolic disease with progressive, devastating neurological manifestations with early mortality and high unmet need. Information on prevalence is scarce and highly variable due to limited newborn screening (NBS) availability, variability of arginine levels in the first days of life, and high rates of misdiagnosis. US birth prevalence was recently estimated via indirect methods at 1.1 cases per million live births. Due to the autosomal recessive nature of ARG1-D we hypothesize that the global prevalence may be more accurately estimated using genetic population databases.MethodsMEDLINE and EMBASE were systematically searched for previously reported disease variants. Disease variants in ARG1-D were annotated wherever possible with allele frequencies from gnomAD. Ethnicity-specific prevalence was calculated using the Hardy–Weinberg equation and applied to generate country-specific carrier frequencies for 38 countries. Finally, documented consanguinity rates were applied to establish a birth prevalence for each country.Results133 of 228 (58%) known causative alleles were annotated with ethnic-specific frequencies. Global birth prevalence for ARG1-D was estimated at 2.8 cases per million live births (country-specific estimates ranged from 0.92 to 17.5) and population prevalence to be 1.4 cases per million people (approximately 1/726,000 people). Birth prevalence estimates were dependent on population demographics and consanguinity rate.ConclusionBirth prevalence of ARG1-D based on genetic database analysis was estimated to be more frequent than previous NBS studies have indicated. There was a higher degree of confidence in North American and European countries due to availability of genetic databases and mutational analysis versus other regions. These findings suggest the need for greater disease education around signs and manifestations of ARG1-D, as well as more widespread testing and standardization of screening for this severe disease in order to appropriately identify patients prior to disease progression.

Diastolic Blood Pressure Alleles Improve Congenital Heart Defect Repair Outcomes.

Congenital heart defects (CHDs) affect 40 000 US births per year, half of which require surgical intervention. Individual differences in surgical outcomes including mortality and complications are not well understood but may be due to genetic variability. We hypothesized that polygenic risk scores (PRSs) for blood pressure in adults are associated with treatments and postsurgical outcomes in children with CHD, as CHD survivors are at higher risk of negative cardiometabolic disease. We used imputed genotype data from pediatric participants requiring surgery for CHD (median age at surgery, 201 days; nmax=2498). Base data for the systolic and diastolic blood pressure PRSs (nmax=760 226) came from published genome-wide association study. The blood pressure PRSs were tested for association with postsurgical outcomes. All effects presented are per SD increase in PRS and adjusted for age, sex, body mass index, surgical complexity score, and first 10 principal components of ancestry. A higher diastolic blood pressure PRS was associated with decreased in-hospital mortality risk (odds ratio, 0.57 [0.39-0.82]; P=0.0022). Additional analyses suggest an interaction between diastolic blood pressure PRS and vasopressor dose. Those with a diastolic blood pressure PRS 1 SD above the mean, receiving a vasopressor dose in the top tertile, were estimated to have 52% (32%-66%) lower risk of in-hospital mortality compared with those with a vasopressor dose in the bottom tertile. These results suggest a genetically determined postsurgical survival advantage for CHD patients with blood pressure increasing alleles. Further study may reveal novel mechanisms contributing to postoperative morbidity and mortality, and this approach may assist in early identification of children at risk for adverse postoperative outcomes.

Association of Medicaid Expansion With Neuraxial Labor Analgesia Use in the United States: A Retrospective Cross-Sectional Analysis.

The Affordable Care Act has been associated with increased Medicaid coverage for childbirth among low-income US women. We hypothesized that Medicaid expansion was associated with increased use of labor neuraxial analgesia. We performed a cross-sectional analysis of US women with singleton live births who underwent vaginal delivery or intrapartum cesarean delivery between 2009 and 2017. Data were sourced from births in 26 US states that used the 2003 Revised US Birth Certificate. Difference-in-difference linear probability models were used to compare changes in the prevalence of neuraxial labor analgesia in 15 expansion and 11 nonexpansion states before and after Medicaid expansion. Models were adjusted for potential maternal and obstetric confounders with standard errors clustered at the state level. The study sample included 5,703,371 births from 15 expansion states and 5,582,689 births from 11 nonexpansion states. In the preexpansion period, the overall rate of neuraxial analgesia in expansion and nonexpansion states was 73.2% vs 76.3%. Compared with the preexpansion period, the rate of neuraxial analgesia increased in the postexpansion period by 1.7% in expansion states (95% CI, 1.6-1.8) and 0.9% (95% CI, 0.9-1.0) in nonexpansion states. The adjusted difference-in-difference estimate comparing expansion and nonexpansion states was 0.47% points (95% CI, -0.63 to 1.57; P = .39). Medicaid expansion was not associated with an increase in the rate of neuraxial labor analgesia in expansion states compared to the change in nonexpansion states over the same time period. Increasing Medicaid eligibility alone may be insufficient to increase the rate of neuraxial labor analgesia.

Multijurisdictional Analyses of Birth Defects: Considering the Common Data Model Approach.

Multijurisdictional Analyses of Birth Defects: Considering the Common Data Model Approach.

The Puzzle of Falling US Birth Rates since the Great Recession

This paper documents a set of facts about the dramatic decline in birth rates in the United States between 2007 and 2020 and explores possible explanations. The overall reduction in the birth rate reflects declines across many groups of women, including teens, Hispanic women, and college-educated white women. The Great Recession contributed to the decline in the early part of this period, but we are unable to identify any other economic, policy, or social factor that has changed since 2007 that is responsible for much of the decline beyond that. Mechanically, the falling birth rate can be attributed to changes in birth patterns across recent cohorts of women moving through childbearing age. We conjecture that the “shifting priorities” of more recent cohorts, reflecting changes in preferences for having children, aspirations for life, and parenting norms, may be responsible. We conclude with a brief discussion about the societal consequences for a declining birth rate and what the United States might do about it.

Population-Based Newborn Screening for Germline TP53 Variants: Clinical Benefits, Cost-Effectiveness, and Value of Further Research.

Identification of children and infants with Li-Fraumeni syndrome prompts tumor surveillance and allows potential early cancer detection. We assessed the clinical benefits and cost-effectiveness of population-wide newborn screening for TP53 variants (TP53-NBS). We simulated the impact of TP53-NBS using data regarding TP53-associated pediatric cancers and pathogenic or likely pathogenic (P/LP) TP53 variants from Surveillance, Epidemiology, and End Results; ClinVar and gnomAD; and clinical studies. We simulated an annual US birth cohort under usual care and TP53-NBS and estimated clinical benefits, life-years, and costs associated with usual care and TP53-NBS. Under usual care, of 4 million newborns, 608 (uncertainty interval [UI] = 581-636) individuals would develop TP53-associated cancers before age 20 years. Under TP53-NBS, 894 individuals would have P/LP TP53 variants detected. These individuals would undergo routine surveillance after detection of P/LP TP53 variants decreasing the number of cancer-related deaths by 7.2% (UI = 4.0%-12.1%) overall via early malignancy detection. Compared with usual care, TP53-NBS had an incremental cost-effectiveness ratio of $106 009 per life-year gained. Probabilistic analysis estimated a 40% probability that TP53-NBS would be cost-effective given a $100 000 per life-year gained willingness-to-pay threshold. Using this threshold, a value of information analysis found that additional research on the prevalence of TP53 variants among rhabdomyosarcoma cases would resolve most of the decision uncertainty, resulting in an expected benefit of 349 life-years gained (or $36.6 million). We found that TP53-NBS could be cost-effective; however, our findings suggest that further research is needed to reduce the uncertainty in the potential health outcomes and costs associated with TP53-NBS.

Social Determinants of Preterm Birth Amongst Non-Hispanic Black Women

Efforts to recognize risk factors for preterm birth (PTB) are essential as this is a leading cause of perinatal mortality in the US. This study aims to identify risk factors that may be drivers of higher preterm birth rates amongst non-Hispanic black women. Population-based retrospective case-control study of the US birth records (2012—2016). Factors potentially associated with preterm birth and considered as indicators of social determinants of health (SDH) were compared between singleton live births of non-Hispanic Black women delivering preterm (< 37 weeks gestation) and term (≥ 37 weeks gestation). Multivariate logistic regression quantified the association between social determinants and PTB such as maternal age, insurance type, education level, and amount of prenatal care, and reported as odds ratios (95% confidence interval, CI). Of 2,763,235 live births to Black women in the US during the study period, 340,480 (12% of births to Black women) occurred < 37 weeks. Factors most strongly associated with preterm birth (P< .001), presented as odds ratio (95% CI) included no prenatal care 3.0 (95% CI, 2.9—3.1) or insufficient prenatal care 2.7 (95% CI, 2.7—2.8); smoking during pregnancy 1.4 (95% CI, 1.43—1.47), age ≥ 35 years 1.3 (95% CI, 1.3—1.35), unmarried 1.18 (95% CI, 1.17—1.19), lack of high school diploma 1.1 (95% CI, 1.12—1.40), lack of father of baby listed on birth certificate 1.22 (1.21—1.23), and Black paternal race 1.10 (1.08—1.12). Utilization of government-funded resources of Medicaid and WIC had opposite influence on PTB risk in Black women, OR 1.08 (1.07—1.09) and 0.83 (0.83—0.84), respectively. Non-Hispanic Black women with older age, smokers, Medicaid insurance, lower education, unmarried, lack of prenatal care, Black paternal race, and lack of father of baby listed on birth record had increased risk of PTB. Addressing these indicators of SDH that contribute to the risk of PTB, specifically amongst Black women, may help to address the racial disparity in adverse perinatal outcomes in the US.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

ALPS Trial Dissemination: Effects on Pregnant People with Diabetes and their Infants

To examine the effects of the Antenatal Late Preterm Steroids (ALPS) trial on late preterm steroid use and neonatal assisted ventilation rates among people with diabetes. Interrupted time series analysis of singleton, liveborn, non-anomalous infants born between 34-36 weeks to women with pre-existing or gestational diabetes using US birth certificate data. The period from Feb 2016 (ALPS trial publication) to Oct 2016 (updated ACOG Committee Opinion publication) was considered the dissemination period. We examined the change in late preterm steroid use and rates of 1) any assisted ventilation and 2) assisted ventilation for >6 hours. Monthly rates before and after the dissemination period were compared between Jan 2014 and Dec 2019, controlling for seasonal variation in the outcomes and monthly distribution of deliveries by week of gestation. 143,707 women with diabetes gave birth during the analysis period; 20.2% of this cohort had pre-gestational diabetes. Figure 1 shows the unadjusted monthly rates of steroid administration and assisted ventilation use in this population and the adjusted linear pre- and post-dissemination period trend. After the ALPS trial publication and the dissemination period, there was an immediate 8.77-percentage point (pp) increase in late preterm steroid use (95% CI 7.76, 9.79). There was no significant change in the rate of assisted ventilation (0.42-pp decrease; 95% CI -1.29, 0.46) or assisted ventilation for more than 6 hours (0.36-pp increase; 95% CI -0.21, 0.94). Similar findings were seen in the subgroup of women with pre-gestational diabetes. The rate of late preterm steroid administration among this population increased substantially after the trial’s dissemination without observable improvement in neonatal assisted ventilation rates. Given the underlying risk of hypoglycemia in the infants of people with diabetes, further research is needed to assess the benefits and potential risks of late preterm steroid administration in this population.

Maternal exposures and risks of congenital heart defects

The causes of congenital heart defects are largely unknown. It is likely that there is both a genetic and an environmental component. It is important to understand the environmental factors as they are potentially modifiable and could help in developing strategies for prevention. In this volume of The Journal, 2 reports focus on these issues. Wang et al report on a study from China on maternal folic acid supplementation and risk for fetal congenital heart defects. The authors took advantage of 2 useful databases that include information on exposure and on outcome. They evaluated mothers taking folic acid or a preparation of multiple micronutrients including folic acid (MMFA). They were also able to examine the timing of use of folic acid supplements. It is useful to do this research in China because they do not have the fortification of food with folic acid as in many other countries. They found that maternal periconceptional supplementation with either folic acid or MMFA was associated with a decreased risk of having an infant with congenital heart defects. There was a greater reduction of risk when folic acid was initiated prior to conception. Bolin et al evaluated the relationship between maternal smoking and congenital heart defects in offspring using data from a US Birth Defects Prevention Study. They found an association between maternal periconceptional smoking and septal defects, tricuspid atresia, and double outlet right ventricle (DORV). Maternal age was also important with mothers who were ≥35 years old at delivery and who smoked >15 cigarette per day in the periconceptional period being more than twice as likely to have a child with a septal defect compared to non-smoking mothers of similar age. Because these are both observational studies, they are subject to limitations. Both analyses attempted to control for confounders but were limited to data on confounders present in the databases used. An important point made by both studies is that exposures early in pregnancy are important because cardiac development begins early in pregnancy. From a public health prevention standpoint, this suggests that interventions should begin pre-pregnancy to have the greatest potential for impact on cardiac development. Articles pages 72 and 79 Maternal Smoking and Congenital Heart Defects, National Birth Defects Prevention Study, 1997-2011The Journal of PediatricsVol. 240PreviewTo assess associations between maternal smoking and congenital heart defects (CHDs) in offspring. Full-Text PDF Maternal Periconceptional Folic Acid Supplementation and Risk for Fetal Congenital Heart DefectsThe Journal of PediatricsVol. 240PreviewTo determine the effects of maternal periconceptional supplementation with folic acid or multiple micronutrients containing folic acid on the prevention of fetal congenital heart defects (CHDs). Full-Text PDF

Declining violence and improving birth outcomes in the US: Evidence from birth certificate data

The decline in crime that occurred in the last decade of the 20th century was one of the most important societal changes in recent US history. In this paper, we leverage the sharp decline in violence that began in the 1990s to estimate the relationship between county-level murder rates and individual-level birth outcomes for Black, Hispanic, and White mothers. Using the FBI's Uniform Crime Reporting data from 1992 to 2002 and individual-level data from more than 30,000,000 US birth certificates, we employ two-way fixed effects models with a rich set of controls to compare births to similar women in the same county who experienced different crime rates during their pregnancies. Elevated murder rates are associated with substantially higher risks of low birth weight for White mothers, low birth weight and small for gestational age among Black mothers, and small for gestational age among Hispanic mothers. Sensitivity analyses show that the existence of confounders that would invalidate these inferences is highly unlikely, suggesting that we have identified causal relationships, even if some uncertainty about the precision of our estimates remains. These findings have potential implications for prenatal and postpartum care, and they add to a growing body of evidence showing that the “Great American Crime Decline” was strongly linked to improved outcomes among groups that experienced the steepest declines in violence.

Path analysis model of epidural/spinal anesthesia on breastfeeding among healthy nulliparous women: Secondary analysis of the United States Certificate of Live Births 2016.

The effect of epidural/spinal anesthesia during labor on breastfeeding is unclear. Few studies had assessed whether or how medically assisted delivery (operative vaginal delivery or unscheduled cesarean birth) plays a mediating role. We aimed to examine whether the relationship between using epidural/spinal anesthesia and breastfeeding is mediated by increased medically assisted delivery among healthy nulliparous women. A secondary, cross-sectional analysis was conducted using US birth certificate data from 2016 (n=381199). Logistic regression was used to examine associations between factors. Structural equation modeling (SEM) was used to analyze the model fit of the path models and to quantify the direct, indirect, and total effect of anesthesia on breastfeeding at discharge, considering medically assisted delivery as a mediator. Women who were administered epidural/spinal anesthesia were more likely to experience medically assisted delivery (adjusted odds ratio [AOR]: 95% confidence interval [CI] 3.01 (2.91-3.12)) and less likely to be breastfeeding at discharge (0.95 [0.92-0.98]). Operative vaginal and unscheduled cesarean deliveries were significantly associated with nonbreastfeeding at discharge (0.81 [0.77-0.84] and 0.81 [0.79-0.84], respectively). SEM revealed excellent model fit for our model. The indirect effect was significant (β=-0.038; 95% CI, -0.043 to -0.033), as was the total effect (β=-0.038; 95% CI, -0.043 to -0.033). Epidural/spinal anesthesia is associated with nonbreastfeeding at discharge, mediated through medically assisted delivery. Health care providers should consider these risks and provide adequate support to help all parents attain their breastfeeding goals.

Cost-effectiveness Evaluation of the 2021 US Preventive Services Task Force Recommendation for Lung Cancer Screening

The US Preventive Services Task Force (USPSTF) issued its 2021 recommendation on lung cancer screening, which lowered the starting age for screening from 55 to 50 years and the minimum cumulative smoking exposure from 30 to 20 pack-years relative to its 2013 recommendation. Although costs are expected to increase because of the expanded screening eligibility criteria, it is unknown whether the new guidelines for lung cancer screening are cost-effective. To evaluate the cost-effectiveness of the 2021 USPSTF recommendation for lung cancer screening compared with the 2013 recommendation and to explore the cost-effectiveness of 6 alternative screening strategies that maintained a minimum cumulative smoking exposure of 20 pack-years and an ending age for screening of 80 years but varied the starting ages for screening (50 or 55 years) and the number of years since smoking cessation (≤15, ≤20, or ≤25). A comparative cost-effectiveness analysis using 4 independently developed microsimulation models that shared common inputs to assess the population-level health benefits and costs of the 2021 recommended screening strategy and 6 alternative screening strategies compared with the 2013 recommended screening strategy. The models simulated a 1960 US birth cohort. Simulated individuals entered the study at age 45 years and were followed up until death or age 90 years, corresponding to a study period from January 1, 2005, to December 31, 2050. Low-dose computed tomography in lung cancer screening programs with a minimum cumulative smoking exposure of 20 pack-years. Incremental cost-effectiveness ratio (ICER) per quality-adjusted life-year (QALY) of the 2021 vs 2013 USPSTF lung cancer screening recommendations as well as 6 alternative screening strategies vs the 2013 USPSTF screening strategy. Strategies with a mean ICER lower than $100 000 per QALY were deemed cost-effective. The 2021 USPSTF recommendation was estimated to be cost-effective compared with the 2013 recommendation, with a mean ICER of $72 564 (range across 4 models, $59 493-$85 837) per QALY gained. The 2021 recommendation was not cost-effective compared with 6 alternative strategies that used the 20 pack-year criterion. Strategies associated with the most cost-effectiveness included those that expanded screening eligibility to include a greater number of former smokers who had not smoked for a longer duration (ie, ≤20 years and ≤25 years since smoking cessation vs ≤15 years since smoking cessation). In particular, the strategy that screened former smokers who quit within the past 25 years and began screening at age 55 years was associated with screening coverage closest to that of the 2021 USPSTF recommendation yet yielded greater cost-effectiveness, with a mean ICER of $66 533 (range across 4 models, $55 693-$80 539). This economic evaluation found that the 2021 USPSTF recommendation for lung cancer screening was cost-effective; however, alternative screening strategies that maintained a minimum cumulative smoking exposure of 20 pack-years but included individuals who quit smoking within the past 25 years may be more cost-effective and warrant further evaluation.

The limits of small-for-gestational-age as a high-risk category.

SGA (small for gestational age) is widely used to identify high-risk infants, although with inconsistent definitions. Cut points range from 2.5th to 10th percentile of birthweight-for-gestational age. We used receiver operator characteristic curves (ROC) to identify the cut point with maximum sensitivity and specificity (Youden Index), and the area under the curve (AUC), which assesses overall discriminating power. Analysis was conducted on 3,836,034 US births (2015) and 292,279 Norwegian births (2010-14). Birthweight percentiles were calculated using exact birthweights at each week of gestational age, and then summarized across gestational ages. We also conducted a companion analysis of gestational age itself to consider the predictive power of gestational week of birth. Outcomes were neonatal mortality and cerebral palsy, both strongly associated with birthweight. Birthweight percentiles performed poorly in all analyses. The AUC for birthweight percentiles as a discriminator of neonatal mortality was 60% (where 50% is no better than a coin-toss). At such low discrimination, the Youden Index provides no useful SGA cut point. Results in Norway were virtually identical, with an AUC of 58%. The AUC with cerebral palsy as the outcome was even lower, at 54%. In contrast, gestational age had an AUC of 85% as a predictor of neonatal mortality, with < 37 weeks as the optimum cut point. SGA provides surprisingly poor identification of at-risk infants, while gestational age performs well. Similar results in two countries that differ in mean birthweight, percent preterm, and neonatal mortality suggest robustness across populations.

Maternal Cannabis Use in the Perinatal Period: Data From the Pregnancy Risk Assessment Monitoring System Marijuana Supplement, 2016-2018.

To estimate the prevalence of perinatal cannabis use (ie, before and/or during pregnancy); document the frequency, modes, and motivations for use; and identify predictors of perinatal cannabis use. Six states in the Pregnancy Risk Assessment Monitoring System, a state-specific, population-based surveillance system, administered a supplemental questionnaire on perinatal cannabis use in 2016-2018. Women with live births were surveyed 2-6 months postpartum about behaviors ≤ 3 months preconception and during pregnancy. Demographic, psychosocial, and behavioral characteristics were examined in relation to perinatal cannabis use using multinomial regression models. Those who: (1) never used cannabis, (2) only used in preconception period, and (3) used in both preconception and prenatal periods were compared. Among 6428 respondents, 379 (5.8%) used cannabis pre-conceptionally only and 466 (4.4%) used in both the preconception and prenatal periods. Among those using prenatally, most reported smoking as their single mode (87.1%), with the two most common reasons being stress (83.8%) and nausea/vomiting (79.2%). Marital status, race/ethnicity, socioeconomic status, parity, and cigarette and alcohol use were significantly associated with perinatal cannabis use. Single (vs partnered) women were more likely to use cannabis prenatally (odds ratio = 2.4, 95% confidence interval: 1.5, 3.9) and non-Hispanic Black (vs White) women were less likely to use prenatally (odds ratio = 0.4, 95% confidence interval: 0.2, 0.8). Using a population-based sample of US births in six states, several demographic, psychosocial, and behavioral characteristics were identified in relation to perinatal cannabis use. These data are valuable for counseling in prenatal care and investigations of health effects.

Factors Associated With Changes in Pregnancy Intention Among Women Who Were Mothers of Young Children in New York City Following the COVID-19 Outbreak

Early evidence shows a decrease in the number of US births during the COVID-19 pandemic, yet few studies have examined individual-level factors associated with pregnancy intention changes, especially among diverse study populations or in areas highly affected by COVID-19 in the US. To study changes in pregnancy intention following the outbreak of the COVID-19 pandemic and identify factors possibly associated with these changes. A cross-sectional, population-based study was conducted among women who were currently pregnant or had delivered a live infant and responded to a survey emailed to 2603 women (n = 1560). Women who were mothers of young children enrolled in the prospective New York University Children's Health and Environment Study birth cohort were included; women who were not currently pregnant or recently postpartum were excluded. Demographic, COVID-19-related, stress-related, and financial/occupational factors were assessed via a survey administered from April 20 to August 31, 2020. Pregnancy intentions before the COVID-19 pandemic and change in pregnancy intentions following the outbreak. Of the 2603 women who were sent the survey, 1560 (59.9%) who were currently pregnant or had delivered a live infant responded, and 1179 women (75.6%) answered the pregnancy intention questions. Mean (SD) age was 32.2 (5.6) years. Following the outbreak, 30 of 61 (49.2%) women who had been actively trying to become pregnant had ceased trying, 71 of 191 (37.2%) women who had been planning to become pregnant were no longer planning, and 42 of 927 (4.5%) women who were neither planning nor trying were newly considering pregnancy. Among those who ceased trying, fewer than half (13 [43.3%]) thought they would resume after the pandemic. Of those pre-COVID-19 planners/triers who stopped considering or attempting pregnancy, a greater proportion had lower educational levels, although the difference was not statistically significant on multivariable analysis (odds ratio [OR], 2.14; 95% CI, 0.92-4.96). The same was true for those with higher stress levels (OR, 1.09; 95% CI, 0.99-1.20) and those with greater financial insecurity (OR, 1.37; 95% CI, 0.97-1.92. Those who stopped considering or attempting pregnancy were more likely to respond to the questionnaire during the peak of the outbreak (OR, 2.04; 95% CI, 1.01-4.11). Of those pre-COVID-19 nonplanners/nontriers who reported newly thinking about becoming pregnant, a smaller proportion responded during the peak, although the finding was not statistically significant on multivariable analysis (OR, 0.52; 95% CI, 0.26-1.03). Likewise, fewer respondents who were financially insecure reported newly considering pregnancy, although the finding was not statistically significant (OR, 0.69; 95% CI, 0.46-1.03). They were significantly less likely to be of Hispanic ethnicity (OR, 0.27; 955 CI, 0.10-0.71) and more likely to have fewer children in the home (OR, 0.62; 95% CI, 0.40-0.98) or self-report a COVID-19 diagnosis (OR, 2.70; 95% CI, 1.31-5.55). In this cross-sectional study of 1179 women who were mothers of young children in New York City, increased stress and financial insecurity owing to the COVID-19 pandemic paralleled a reduction in pregnancy intention in the early months of the pandemic, potentially exacerbating long-term decreases in the fertility rate.

Preeclampsia Across Pregnancies and Associated Risk Factors: Findings From a High-Risk US Birth Cohort.

BackgroundPreeclampsia increases women's risks for maternal morbidity and future cardiovascular disease. The aim of this study was to identify opportunities for prevention by examining the association between cardiometabolic risk factors and preeclampsia across 2 pregnancies among women in a high‐risk US birth cohort.Methods and ResultsOur sample included 618 women in the Boston Birth Cohort with index and subsequent pregnancy data collected using standard protocols. We conducted log‐binomial univariate regression models to examine the association between preeclampsia in the subsequent pregnancy (defined as incident or recurrent preeclampsia) and cardiometabolic risk factors (ie, obesity, hypertension, diabetes mellitus, preterm birth, low birth weight, and gestational diabetes mellitus) diagnosed before and during the index pregnancy, and between index and subsequent pregnancies. At the subsequent pregnancy, 7% (36/540) had incident preeclampsia and 42% (33/78) had recurrent preeclampsia. Compared with women without obesity, women with obesity had greater risk of incident preeclampsia (unadjusted risk ratio [RR], 2.2 [95% CI, 1.1–4.5]) and recurrent preeclampsia (unadjusted RR, 3.1 [95% CI, 1.5–6.7]). Preindex pregnancy chronic hypertension and diabetes mellitus were associated with incident, but not recurrent, preeclampsia (hypertension unadjusted RR, 7.9 [95% CI, 4.1–15.3]; diabetes mellitus unadjusted RR, 5.2 [95% CI, 2.5–11.1]. Women with new interpregnancy hypertension versus those without had a higher risk of incident and recurrent preeclampsia (incident preeclampsia unadjusted RR, 6.1 [95% CI, 2.9–13]); recurrent preeclampsia unadjusted RR, 2.4 [95% CI, 1.5–3.9]).ConclusionsIn this diverse sample of high‐risk US women, we identified modifiable and treatable risk factors, including obesity and hypertension for the prevention of preeclampsia.