Amy P. Case

Is maternal parity an independent risk factor for birth defects

BACKGROUND Although associations between maternal parity and birth defects have been observed previously, few studies have focused on the possibility that parity is an independent risk factor for birth defects. We investigated the relation between levels of parity and a range of birth defects, adjusting each defect group for the same covariates. METHODS We included infants who had an estimated delivery date between 1997 and 2007 and participated in the National Birth Defects Prevention Study, a multisite case-control study. Cases included infants or fetuses belonging to 38 phenotypes of birth defects (n = 17,908), and controls included infants who were unaffected by a major birth defect (n = 7173). Odds ratios (ORs) were adjusted for 12 covariates using logistic regression. RESULTS Compared with primiparous mothers, nulliparous mothers were more likely to have infants with amniotic band sequence, hydrocephaly, esophageal atresia, hypospadias, limb reduction deficiencies, diaphragmatic hernia, omphalocele, gastroschisis, tetralogy of Fallot, and septal cardiac defects, with significant ORs (1.2 to 2.3). Compared with primiparous mothers, multiparous mothers had a significantly increased risk of omphalocele, with an OR of 1.5, but had significantly decreased risk of hypospadias and limb reduction deficiencies, with ORs of 0.77 and 0.77. CONCLUSIONS Nulliparity was associated with an increased risk of specific phenotypes of birth defects. Most of the phenotypes associated with nulliparity in this study were consistent with those identified by previous studies. Research into biologic or environmental factors that are associated with nulliparity may be helpful in explaining some or all of these associations.

Awareness and attitudes regarding prenatal testing among Texas women of childbearing age

Despite increased visibility and availability of prenatal testing procedures, very little is known about the attitudes among the populace toward these procedures. Using a computer assisted telephone interview of pregnant and non-pregnant women of childbearing age we analyze awareness and attitudes regarding prenatal tests among a diverse group of women of childbearing age in Texas. We also examine maternal characteristics associated with awareness and the willingness to undergo these procedures. While 89% were aware that such tests are available, younger, black and less educated women were less likely to know about prenatal tests for birth defects. Seventy-two percent of respondents said they would want their baby tested while Hispanic and black women were significantly more likely to express an interest than non-Hispanic whites. This study demonstrates the variability of knowledge and beliefs and confirms the importance of taking time to understand an individual’s personal beliefs, knowledge and attitudes about prenatal diagnosis.

Preconceptional folic acid‐containing supplement use in the national birth defects prevention study

BACKGROUND Despite public health campaigns encouraging women to take a daily folic acid supplement, the proportion of reproductive age women, in the United States, who comply with this recommendation is less than optimal. The objective of this analysis was to identify predictors of preconceptional folic acid-containing supplement use to define subgroups of women who may benefit from targeted folic acid campaigns. METHODS This study included 6570 mothers of live born infants from the control population of National Birth Defects Prevention Study (1997-2005). Logistic regression analyses were used to identify predictors of preconceptional folic acid supplementation. A classification and regression tree (CART) analysis was used to define subgroups of women with different patterns of preconceptional folic acid supplementation. RESULTS Race/ethnicity, education, age at delivery, nativity, employment, income, number of dependents, smoking, and birth control use were significantly associated with preconceptional folic acid-containing supplement use. Based on a CART analysis, education, race/ethnicity, and age were the most distinguishing factors between women with different preconceptional supplementation patterns. Non-white women with <4 years of a college education were the least likely to use folic acid-containing supplements (11%). However, even in the most compliant subgroup (women with ≥4 years of college), only 60% of women supplemented with folic acid. CONCLUSION These results demonstrate the need for continued efforts to increase folic acid supplementation among all reproductive aged women. However, the success of such efforts may be improved if maternal characteristics such as education, race/ethnicity, and age, are considered in the development of future interventions.

Maltreatment of Children Under Age 2 With Specific Birth Defects: A Population-Based Study.

BACKGROUND AND OBJECTIVES: Children with disabilities are at an increased risk for maltreatment. However, the risk of maltreatment is unknown for children with specific types of birth defects. This study was conducted to determine whether the risk and predictors of maltreatment differ between children with and without 3 birth defects: Down syndrome, cleft lip with/without cleft palate, and spina bifida. METHODS: This population-based study of substantiated childhood maltreatment was conducted in Texas from 2002 to 2011. Linked data were used to describe the risk and types of maltreatment that occurred before age 2 years in children with and without specific birth defects. Poisson regression was used to identify predictors of maltreatment and assess differences in those predictors between children with and without these specific birth defects. RESULTS: The risk of maltreatment (any type) in children with cleft lip with/without cleft palate and spina bifida was increased by 40% and 58%, respectively, compared with children with no birth defects. The risk of any maltreatment was similar between children with Down syndrome and unaffected children. Across birth defect groups, the risk of medical neglect was 3 to 6 times higher than in the unaffected group. Child-, family-, and neighborhood-level factors predicted maltreatment in children with and without birth defects. CONCLUSIONS: The overall risk of substantiated maltreatment was significantly higher for some but not all birth defect groups. The factors associated with increased risk were similar across groups. Enhancement of existing maltreatment prevention and early intervention programs may be effective mechanisms to provide at-risk families additional support.

Short interpregnancy interval and gastroschisis risk in the national birth defects prevention study

BACKGROUND The micronutrient depletion hypothesis proposes that consecutive pregnancies spaced too closely may leave insufficient time for maternal micronutrient replenishment. Short interpregnancy intervals (IPI) have been associated with an increased risk for several adverse pregnancy outcomes, but an association with gastroschisis risk has not been previously explored. METHODS Within a population-based, case-control study, we evaluated the association between IPI length and gastroschisis risk using multivariable logistic regression models to estimate gastroschisis odds ratios for IPI <12 months and 12 to 17 months relative to those 18 to 23 months. We further evaluated the association between IPI and gastroschisis risk stratified by maternal age, periconceptional multivitamin use, preceding pregnancy outcome, study center region, and season of conception to explore whether observed associations were compatible with the hypothesis of maternal micronutrient depletion. RESULTS For women with IPI <12 months, the adjusted odds ratio (aOR) was 1.7 (95% confidence interval [CI]: 1.1-2.5). The magnitude of the observed effect did not differ among strata of maternal age or periconceptional multivitamin use. However, the association was more pronounced after a miscarriage or termination (aOR: 2.5; 95% CI: 1.1-5.6) and among women who resided in northern study areas (aOR: 2.8; 95% CI: 1.3-5.9). The higher risk observed with short IPI among women in northern study areas was attenuated for spring/summer conceptions. CONCLUSION Short IPI was associated with an increased risk for gastroschisis, particularly among women whose preceding pregnancy resulted in a miscarriage or termination and among those who resided in northern study areas with winter/fall conception.

Prenatal diagnosis and cesarean section in a large, population-based birth defects registry

Objective. To describe the patterns of cesarean section (CS) and vaginal delivery by type of birth defect and determine whether prenatal diagnosis predicts a higher or lower likelihood of CS for selected defect categories. Methods. Data from a large population-based registry were analyzed to determine percentages of vaginal versus CS delivery for each of 49 categories of birth defects. Odds ratios and statistical significance were computed to determine if a record of prenatal diagnosis (PND) predicted delivery mode. Cases were liveborn children with any of these defects born in Texas between 1997 and 2005. Results. Forty-three percent of infants in the study were delivered by CS, with a range of 25.3% (aniridia) to 62.4% (spina bifida). A record of prenatal diagnosis of the primary assigned birth defect was found in 43.0% of all records but varied substantially by defect category. PND significantly predicted higher CS percentages for spina bifida without anencephaly, encephalocele, hydrocephaly, transposition of the great vessels, ventricular septal defect, pulmonary valve atresia/stenosis, craniosynostosis, diaphragmatic hernia, gastroschisis, and trisomy 21. Vaginal delivery was predicted by PND of anencephaly, agenesis, aplasia, or hypoplasia of the lung, renal agenesis or dysgenesis, and trisomy 18. Conclusion. Texas children with birth defects are more likely to have been delivered by CS than the population in general. For several types of defects, prenatal diagnosis is predictive of higher odds of CS; for others, especially fatal defects, PND predicts lower CS likelihood.

Proximity of pediatric genetic services to children with birth defects in Texas

BACKGROUND Families of children with major structural malformations often benefit greatly from genetic services. However, these services may not be readily available in all areas. The purpose of this study was to use data from a statewide birth defects registry and geographic information system methodology to compare the spatial distribution and to summarize the distance of pediatric clinical genetic service providers in relation to residential addresses of children with selected birth defects in Texas. METHODS Live-born children delivered between 1999-2004 in the Texas Birth Defects Registry with major structural defects and chromosomal anomalies were selected by a clinical geneticist according to diagnosis code. Mothers address at delivery of the case infants was geocoded as was the location of offices where clinical geneticists in Texas see pediatric patients. Using geographic information system tools, the authors then computed distance from each case mothers residence to the location of the nearest office where pediatric patients can be seen by clinical geneticists, summarized these distances, and graphically plotted the location of each case in relation to the nearest provider. RESULTS Nearly 25,000 Registry cases met the criteria for selection for geocoding. Of those, 22,875 (91.8%) were successfully geocoded to street level. CONCLUSIONS Although 82% of addresses were within 30 miles of the nearest pediatric genetic clinic, 14% lived 31-100 miles from the nearest facility, and 4% of case families would need to drive more than 100 miles, including some who live in midsized cities, indicating geographic disparities in access to these necessary services.

Public health projects for preventing the recurrence of neural tube defects in the United States

BACKGROUND The recurrence risk for neural tube defects (NTDs) in subsequent pregnancies is approximately 3%, or 40 times the background risk. Prevention projects target these high-risk women to increase their folic acid consumption during the periconceptional period, a behavior which decreases their recurrence risk by at least 85%. This study surveyed birth defect surveillance programs to assess their NTD recurrence prevention activities and to identify components of intervention projects that might be implemented in states with limited resources. METHODS In 2005, the National Birth Defects Prevention Network developed and distributed an online survey to primary state birth defects surveillance contacts for the purpose of gathering information on NTD recurrence prevention activities in the United States. RESULTS Responses came from 37 contacts in 34 states and Puerto Rico. There were 13 active NTD recurrence prevention projects, four past projects, and three planned projects. Fifteen past and present projects recommended that women with a prior NTD-affected birth take 4.0 mg of folic acid daily, and four projects provided folic acid to the women. Reasons given for not having an NTD recurrence prevention project included staffing limitations (53%), lack of funds (47%), lack of priority (18%), and confidentiality/privacy concerns (6%). CONCLUSIONS Only 15 states and Puerto Rico had or were planning NTD recurrence prevention projects. An NTD recurrence prevention project using minimal resources should consist of timely case ascertainment, educational materials, and mechanisms for disseminating these materials.

Periconceptional Risk Factors for Birth Defects among Younger and Older Teen Mothers.

STUDY OBJECTIVES We sought to determine whether selected periconceptional health behaviors that influence risk for birth defects differ between older and younger adolescents and whether pregnancy intention predicts more positive preconception health behaviors among teens. DESIGN AND PARTICIPANTS We analyzed interview responses from 954 adolescent control group participants from the National Birth Defects Prevention Study who delivered live infants during 1997-2007. MAIN OUTCOME MEASURES Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated for factors of interest by age categories (13-15, 16-17, and 18 years, relative to 19 years). To construct a composite periconceptional behavior index, we summed the following healthy behaviors: nonsmoker, nondrinker, folic acid supplementation, and eating 5 or more servings of fruits and vegetables per day. RESULTS Analyses indicated that women in the youngest group (13-15 years of age) were more likely to be Hispanic (aOR 2.83, 95% CI 1.40-5.70) and less likely to engage in some unhealthy pregnancy-related behaviors compared with 19-year-olds, such as smoking (aOR 0.45, 95% CI 0.20-0.99) and being overweight or obese (aOR 0.32, 95% CI 0.16-0.61). However, they were also less likely to have taken periconceptional folic acid (aOR 0.44, 95% CI 0.21-0.90). About one-third of teen mothers indicated that their pregnancies had been intended. Among 18- and 19-year-olds, this predicted a higher mean value for the composite periconceptional behavior index (2.30 versus 1.94, P ≤ .01). CONCLUSIONS Teen mothers are not a homogeneous group. Each age subgroup presents varied demographic and behavioral factors that put them at varying levels of risk for birth defects. Furthermore, caregivers should not assume that teens do not plan pregnancies or that they need not be informed of the importance of periconceptional health.

Hospitalization charges for children with birth defects in Texas, 2001 to 2010.

BACKGROUND State-specific information about hospitalizations of children with birth defects can improve understanding of changes in occurrence, treatment practices, and health care financing policies. This study analyzed aggregated data on hospital charges and length of stay for a large, diverse population. METHODS We extracted hospitalization data for children diagnosed with birth defects from the Texas Hospital Inpatient Discharge Public Use Data File (2001-2010). Analyses compared total charges and length of stay for children with and without a diagnosis code of any birth defect among 45 standard categories. We also examined trends for total charges by expected payer type. RESULTS In Texas, 431,296 hospital stays were reported for children with birth defects, with total charges of