April L. Dawson

Birth Defects Among Fetuses and Infants of US Women With Evidence of Possible Zika Virus Infection During Pregnancy

Importance Understanding the risk of birth defects associated with Zika virus infection during pregnancy may help guide communication, prevention, and planning efforts. In the absence of Zika virus, microcephaly occurs in approximately 7 per 10 000 live births. Objective To estimate the preliminary proportion of fetuses or infants with birth defects after maternal Zika virus infection by trimester of infection and maternal symptoms. Design, Setting, and Participants Completed pregnancies with maternal, fetal, or infant laboratory evidence of possible recent Zika virus infection and outcomes reported in the continental United States and Hawaii from January 15 to September 22, 2016, in the US Zika Pregnancy Registry, a collaboration between the CDC and state and local health departments. Exposures Laboratory evidence of possible recent Zika virus infection in a maternal, placental, fetal, or infant sample. Main Outcomes and Measures Birth defects potentially Zika associated: brain abnormalities with or without microcephaly, neural tube defects and other early brain malformations, eye abnormalities, and other central nervous system consequences. Results Among 442 completed pregnancies in women (median age, 28 years; range, 15-50 years) with laboratory evidence of possible recent Zika virus infection, birth defects potentially related to Zika virus were identified in 26 (6%; 95% CI, 4%-8%) fetuses or infants. There were 21 infants with birth defects among 395 live births and 5 fetuses with birth defects among 47 pregnancy losses. Birth defects were reported for 16 of 271 (6%; 95% CI, 4%-9%) pregnant asymptomatic women and 10 of 167 (6%; 95% CI, 3%-11%) symptomatic pregnant women. Of the 26 affected fetuses or infants, 4 had microcephaly and no reported neuroimaging, 14 had microcephaly and brain abnormalities, and 4 had brain abnormalities without microcephaly; reported brain abnormalities included intracranial calcifications, corpus callosum abnormalities, abnormal cortical formation, cerebral atrophy, ventriculomegaly, hydrocephaly, and cerebellar abnormalities. Infants with microcephaly (18/442) represent 4% of completed pregnancies. Birth defects were reported in 9 of 85 (11%; 95% CI, 6%-19%) completed pregnancies with maternal symptoms or exposure exclusively in the first trimester (or first trimester and periconceptional period), with no reports of birth defects among fetuses or infants with prenatal exposure to Zika virus infection only in the second or third trimesters. Conclusions and Relevance Among pregnant women in the United States with completed pregnancies and laboratory evidence of possible recent Zika infection, 6% of fetuses or infants had evidence of Zika-associated birth defects, primarily brain abnormalities and microcephaly, whereas among women with first-trimester Zika infection, 11% of fetuses or infants had evidence of Zika-associated birth defects. These findings support the importance of screening pregnant women for Zika virus exposure.

Hospitalizations, costs, and mortality among infants with critical congenital heart disease: How important is timely detection?

BACKGROUND Critical congenital heart disease (CCHD) was recently added to the U.S. Recommended Uniform Screening Panel for newborns. States considering screening requirements may want more information about the potential impact of screening. This study examined potentially avoidable mortality among infants with late detected CCHD and assessed whether late detection was associated with increased hospital resource use during infancy. METHODS This was a state-wide, population-based, observational study of infants with CCHD (n = 3603) born 1998 to 2007 identified by the Florida Birth Defects Registry. We examined 12 CCHD conditions that are targets of newborn screening. Late detection was defined as CCHD diagnosis after the birth hospitalization. Deaths potentially avoidable through screening were defined as those that occurred outside a hospital following birth hospitalization discharge and those that occurred within 3 days of an emergency readmission. RESULTS For 23% (n = 825) of infants, CCHD was not detected during the birth hospitalization. Death occurred among 20% (n = 568/2,778) of infants with timely detected CCHD and 8% (n = 66/825) of infants with late detected CCHD, unadjusted for clinical characteristics. Potentially preventable deaths occurred in 1.8% (n = 15/825) of infants with late detected CCHD (0.4% of all infants with CCHD). In multivariable models adjusted for selected characteristics, late CCHD detection was significantly associated with 52% more admissions, 18% more hospitalized days, and 35% higher inpatient costs during infancy. CONCLUSION Increased CCHD detection at birth hospitals through screening may lead to decreased hospital costs and avoid some deaths during infancy. Additional studies conducted after screening implementation are needed to confirm these findings.

Factors associated with late detection of critical congenital heart disease in newborns.

OBJECTIVES: Critical congenital heart disease (CCHD) was recently added to the US Recommended Uniform Screening Panel for newborns. This study assessed whether maternal/household and infant characteristics were associated with late CCHD detection. METHODS: This was a statewide, population-based, retrospective, observational study of infants with CCHD born between 1998 and 2007 identified by using the Florida Birth Defects Registry. We examined 12 CCHD conditions that are primary and secondary targets of newborn CCHD screening using pulse oximetry. We used Poisson regression models to analyze associations between selected characteristics (eg, CCHD type, birth hospital nursery level [highest level available in the hospital]) and late CCHD detection (defined as diagnosis after the birth hospitalization). RESULTS: Of 3603 infants with CCHD and linked hospitalizations, CCHD was not detected during the birth hospitalization for 22.9% (n = 825) of infants. The likelihood of late detection varied by CCHD condition. Infants born in a birth hospital with a level I nursery only (adjusted prevalence ratio: 1.9 [95% confidence interval: 1.6–2.2]) or level II nursery (adjusted prevalence ratio: 1.5 [95% confidence interval: 1.3–1.7]) were significantly more likely to have late-detected CCHD compared with infants born in a birth hospital with a level III (highest) nursery. CONCLUSIONS: After controlling for the selected characteristics, hospital nursery level seems to have an independent association with late CCHD detection. Thus, perhaps universal newborn screening for CCHD could be particularly beneficial in level I and II nurseries and may reduce differences in the frequency of late diagnosis between birth hospital facilities.

Hospitalizations and Associated Costs in a Population-Based Study of Children with Down Syndrome Born in Florida

BACKGROUND Our objective was to examine differences in hospital resource usage for children with Down syndrome by age and the presence of other birth defects, particularly severe and nonsevere congenital heart defects (CHDs). METHODS This was a retrospective, population-based, statewide study of children with Down syndrome born 1998 to 2007, identified by the Florida Birth Defects Registry (FBDR) and linked to hospital discharge records for 1 to 10 years after birth. To evaluate hospital resource usage, descriptive statistics on number of hospitalized days and hospital costs were calculated. Results were stratified by isolated Down syndrome (no other coded major birth defect); presence of severe and nonsevere CHDs; and presence of major FBDR-eligible birth defects without CHDs. RESULTS For 2552 children with Down syndrome, there were 6856 inpatient admissions, of which 68.9% occurred during the first year of life (infancy). Of the 2552 children, 31.7% (n = 808) had isolated Down syndrome, 24.0% (n = 612) had severe CHDs, 36.3% (n = 927) had nonsevere CHDs, and 8.0% (n = 205) had a major FBDR-eligible birth defect in the absence of CHD. Infants in all three nonisolated DS groups had significantly higher hospital costs compared with those with isolated Down syndrome. From infancy through age 4, children with severe CHDs had the highest inpatient costs compared with children in the other sub-groups. CONCLUSION Results support findings that for children with Down syndrome the presence of other anomalies influences hospital use and costs, and children with severe CHDs have greater hospital resource usage than children with other CHDs or major birth defects without CHDs.

Antidepressant prescription claims among reproductive-aged women with private employer-sponsored insurance - United States 2008-2013

Antidepressant medication use during pregnancy has been increasing in the United States (1). Many women require antidepressants on an ongoing basis, and a clear consensus on the safest medication options for both the mother and her fetus does not exist (2). Given that half of all U.S. pregnancies are unplanned (3), antidepressant use will occur during the first weeks of pregnancy, a critical period for fetal development. To understand trends among women of reproductive age, CDC used Truven Healths MarketScan Commercial Claims and Encounters data* to estimate the number of antidepressant prescriptions filled by women aged 15-44 years with private employer-sponsored insurance. During 2008-2013, an average of 15.4% of women aged 15-44 years filled at least one prescription for an antidepressant in a single year. The most frequently filled antidepressants included sertraline, bupropion, and citalopram. Prescribing of antidepressants is common, and research on antidepressant safety during pregnancy needs to be accelerated to provide evidence-based information to health care providers and women about the potential risks for antidepressant exposure before and during pregnancy and between pregnancies.

Factors associated with high hospital resource use in a population-based study of children with orofacial clefts

BACKGROUND Little is known about population-based maternal, child, and system characteristics associated with high hospital resource use for children with orofacial clefts (OFC) in the US. METHODS This was a statewide, population-based, retrospective observational study of children with OFC born between 1998 and 2006, identified by the Florida Birth Defects Registry whose records were linked with longitudinal hospital discharge records. We stratified the descriptive results by cleft type [cleft lip with cleft palate, cleft lip, and cleft palate] and by isolated versus nonisolated OFC (accompanied by other coded major birth defects). We used Poisson regression to analyze associations between selected characteristics and high hospital resource use (≥90th percentile of estimated hospitalized days and inpatient costs) for birth, postbirth, and total hospitalizations initiated before age 2 years. RESULTS Our analysis included 2,129 children with OFC. Infants who were born low birth weight (<2500 grams) were significantly more likely to have high birth hospitalization costs for CLP (adjusted prevalence ratio: 1.6 [95% confidence interval: 1.0-2.7]), CL (adjusted prevalence ratio: 3.0 [95% confidence interval: 1.1-8.1]), and CP (adjusted prevalence ratio: 2.3 [95% confidence interval: 1.3-4.0]). Presence of multiple birth defects was significantly associated with a three- to eleven-fold and a three- to nine-fold increase in the prevalence of high costs and number of hospitalized days, respectively; at birth, postbirth before age 2 years and overall hospitalizations. CONCLUSION Children with cleft palate had the greatest hospital resources use. Additionally, the presence of multiple birth defects contributed to greater inpatient days and costs for children with OFC.

Maternal exposure to methotrexate and birth defects: a population-based study.

Methotrexate is an anti‐folate medication that is associated with increased risk of multiple birth defects. Using data from the National Birth Defects Prevention Study, a case‐control study of major birth defects in the United States, we examined mothers exposed to methotrexate. The study population included mothers of live‐born infants without major birth defects (controls) and mothers of fetuses or infants with a major birth defect (cases), with expected dates of delivery between October 1997 and December 2009. Mothers of cases and controls were asked detailed questions concerning pregnancy history, demographic information, and exposures in a telephone interview. Approximately 0.06% (n = 16/27,623) of case and 0.04% (n = 4/10,113) of control mothers reported exposure to methotrexate between 3 months prior to conception through the end of pregnancy. Of the 16 case infants, 11 (68.8%) had a congenital heart defect (CHD). The observed CHDs included atrial septal defects, tetralogy of Fallot, valvar pulmonary stenosis, ventricular septal defects (VSDs), and total anomalous pulmonary venous return. One case infant had microtia in addition to a VSD and another had VACTER association. Exposed cases without a CHD had one of the following birth defects: cleft palate, hypospadias, congenital diaphragmatic hernia, or craniosynostosis. Based on a limited number of methotrexate‐exposed mothers, our findings support recent case reports suggesting an association between early pregnancy exposure to methotrexate and CHDs. Because of the rarity of maternal periconceptional exposure to methotrexate, long‐term, population‐based case‐control studies are needed to confirm these findings and better evaluate the association between methotrexate and birth defects.

Twinning and major birth defects, National Birth Defects Prevention Study, 1997–2007

Background Twinning has been associated with many types of birth defects, although previous studies have had inconsistent findings. Many studies lack information about potential confounders, particularly use of fertility treatment. Our objective was to assess the association between twinning and birth defects in the National Birth Defects Prevention Study (NBDPS). Methods We used data from the NBDPS, a population-based, case–control study of major birth defects in the USA, to evaluate associations between twinning and birth defects. The study population included mothers of twin and singleton controls (live-born infants without major birth defects), and cases (fetuses or infants with a major birth defect) born October 1997–December 2007. Adjusted ORs and 95% CIs were estimated using multivariable logistic regression stratified by use of fertility treatment. Twin sex-pairing data and a simulation approach were used to estimate the zygosity of twins. Results In the unassisted conception stratum, we observed significant positive associations between twinning and 29 of 45 defect groups. The largest effect estimates were observed for multiple ventricular septal defects and cloacal exstrophy. Among mothers reporting any use of fertility treatments, we observed a significant association with twinning for 5 of 25 defect groups, with the largest effect estimates for hypoplastic left heart syndrome and omphalocele. OR estimates in the estimated monozygotic stratum were generally further from the null than in the dizygotic stratum. Conclusions Compared with singletons, a wide range of birth defects are significantly more common among twins. Birth defect risk in twins may be differential by use of fertility treatment.

Maternal exposures in the National Birth Defects Prevention Study: Time trends of selected exposures.

BACKGROUND Our objective was to describe time trends in selected pregnancy exposures in the National Birth Defects Prevention Study (NBDPS). METHODS We analyzed data from the NBDPS, a multi-site case-control study of major birth defects, for mothers of live-born infants without birth defects (controls), with an expected date of delivery (EDD) from 1998 to 2011. Mothers from the 10 participating centers across the United States were interviewed by phone between 6 weeks and 2 years after the EDD. We focused on maternal race/ethnicity and five maternal risk factors: obesity, use of folic acid-containing multivitamins, opioid analgesics, selective serotonin reuptake inhibitors, and loratadine because of their prevalence of use and some reports of associations with major birth defects. Prevalence time trends were examined using the Kendalls τβ test statistic. RESULTS The exposure trend analysis included 11,724 control mothers with EDDs from 1998 to 2011. We observed a significant increase in obesity prevalence among control mothers, as well as use of selective serotonin reuptake inhibitors and loratadine. We also observed an increase in periconceptional use of folic acid-containing multivitamins. Some of the time trends varied by race/ethnicity. No remarkable trend in the overall use of opioid analgesics was observed. The racial/ethnic distribution of mothers changed slightly during the study period. CONCLUSION Long-term, population-based case-control studies continue to be an effective way to assess exposure-birth defects associations and provide guidance to health care providers. However, investigators examining rare outcomes covering many years of data collection need to be cognizant of time trends in exposures.

Maternal Use of Opioids During Pregnancy and Congenital Malformations: A Systematic Review

The objective of this report was to systematically review the available literature on maternal opioid use during pregnancy and congenital malformations. CONTEXT: Opioid use and abuse have increased dramatically in recent years, particularly among women. OBJECTIVES: We conducted a systematic review to evaluate the association between prenatal opioid use and congenital malformations. DATA SOURCES: We searched Medline and Embase for studies published from 1946 to 2016 and reviewed reference lists to identify additional relevant studies. STUDY SELECTION: We included studies that were full-text journal articles and reported the results of original epidemiologic research on prenatal opioid exposure and congenital malformations. We assessed study eligibility in multiple phases using a standardized, duplicate review process. DATA EXTRACTION: Data on study characteristics, opioid exposure, timing of exposure during pregnancy, congenital malformations (collectively or as individual subtypes), length of follow-up, and main findings were extracted from eligible studies. RESULTS: Of the 68 studies that met our inclusion criteria, 46 had an unexposed comparison group; of those, 30 performed statistical tests to measure associations between maternal opioid use during pregnancy and congenital malformations. Seventeen of these (10 of 12 case-control and 7 of 18 cohort studies) documented statistically significant positive associations. Among the case-control studies, associations with oral clefts and ventricular septal defects/atrial septal defects were the most frequently reported specific malformations. Among the cohort studies, clubfoot was the most frequently reported specific malformation. LIMITATIONS: Variabilities in study design, poor study quality, and weaknesses with outcome and exposure measurement. CONCLUSIONS: Uncertainty remains regarding the teratogenicity of opioids; a careful assessment of risks and benefits is warranted when considering opioid treatment for women of reproductive age.