Performing Department
Animal Science
Non Technical Summary
This project will examine the associations between geographical factors with maternal health and pregnancy outcomes, with an emphasis on rural health. This project will also assess the risk of benzoic acid in pregnant women.Results of this study will provide differential risk factors for pregnancy outcomes in urban and rural communities in Michigan. The results will provide an understanding of the importance of access to year-round supply of fresh vegetables and fruits for optimum pregnancy outcomes. The project will also provide a health risk assessment of benzoic acid for pregnant women. In the past 30 years, the overall infant mortality rate (IMR) in the US decreased from greater than 15.0 per 1000 birth to the current 6.1 per 1000 in 2010. However, infant mortality rate in the United States continues to lag behind other wealthy countries. A newborn in the U.S. is 2.7 times as likely to die during the first year than one born in Finland and Japan, where the IMRs are 2.3 per 1000. Compared to the IMRs of infants born in Portugal (2.5 per 1000), Czech Republic, (2.7 per 1000), and Norway, (2.8 per 1000), US babies are more than twice as likely to die in the first year of their lives. While the elevated infant mortality rates in the U.S. are mostly associated with low education populations in the country, educational level alone does not explain the extraordinarily high IMRs, because over 85% of the adult population in the U.S. have completed high school, while less than 20% Portuguese have attained the same level of education. Furthermore, in the U.S., infant mortality rates remain 0.7 -1.3 per 1000 higher in rural areas than urban areas. This project will examine the associations between geographical factors with maternal health and pregnancy outcomes, which include low birth weight, preterm birth, birth defects, and infant mortality, with a focus on Michigan rural health. The main geographical factor will be accessibility to retail stores and markets for fresh fruits and vegetables. The pregnancy outcomes to be analyzed will include birth weight, birth defects, and infant survival, from 2000-2014, using Michigan birth data. The studies are designed based on the working hypothesis that food behavior and rural environmental and geographical factors can affect pregnancy outcomes independently or by interacting with maternal socioeconomic factors on pregnancy outcomes. The geographical and socioeconomic factors examined in the studies will include accessibility to fresh fruits and vegetables, educational levels, marital status, household income, type of health insurance, and accessibility and driving distance to health care facilities.To examine the effect of lack of access to year-round fresh vegetables and fruits, we will also conduct risk assessment for food preservatives that could affect directly the body's detoxification capability or indirectly affect neurotransmission in the nervous system, such as the effect of benzoic acid on glycine. This part of the project is designed based on the working hypothesis that distances to markets for fresh fruits and vegetables influence family food behavior, and the lack of year-round accessibility to fresh fruits and vegetables, in turn, is a risk factor for maternal obesity and associated poor pregnancy outcomes. Distance traveled to markets for fresh fruits and vegetables will be examined as the main risk factor for maternal obesity and undesirable pregnancy outcomes. Other known risk factors for maternal health and infant mortality will be examined as co-factors in the analyses.
Animal Health Component
0%
Research Effort Categories
Basic
20%
Applied
40%
Developmental
40%
Goals / Objectives
This project will examineassociations between geographical factors with maternal health and pregnancy outcomes, with an emphasis on rural health. This project will also assess the risk of benzoic acid in pregnant women. The objectives are (a)To examine differential risk factors associated pregnancy outcomes in the urban and rural communities in Michigan, (b) To examine the association between the locations of food retail stores and pregnancy outcomes in Michigan, and (c) To assess the health risk of exposure to benzoates in pregnant women.
Project Methods
For Objective (a): Michigan birth and infant death data, from 2000 to 2014, including delivery information, parental demographic information, maternal health information, maternal tobacco and alcohol use, hospital of delivery and treatments, type of hospital payments, and geocodes of maternal residences, will be obtained from the Michigan Department of Community HealthTo assess maternal risk factors, the data files will contain information on race, ancestry, education, marital status, source of payment, number of previous children born alive now living, number of previous children born alive now dead, number of previous children born dead, birthday of last live birth, date of last fetal death, maternal height and body weight before this pregnancy, the month during pregnancy when prenatal care began, number of prenatal visits during pregnancy, date of last prenatal care, date of last menstruation, calculated and estimated weeks of gestation, weight gain during pregnancy, maternal tobacco and alcohol use, date quit smoking, others in household that smoke, maternal birthday and age, mother transferred prior to delivery, hospital mom transferred from, hepatitis-B immunization and globulin given, dates of hepatitis-B immunization and globulin given, and other health risks, including anemia, cardiac disease, diabetes prior to this pregnancy, diabetes diagnosis in this pregnancy, renal disease, lung disease, genital herpes, oligohydramnios, hemoglobin, chronic and pregnancy hypertension, eclampsia, incomplete cervical dilation, previous large baby, previous small baby, previous preterm birth, previous poor pregnancy, renal disease, Rh sensitivity, vaginal bleeding during this pregnancy prior to the onset of labor, uterine bleeding, pregnancy resulted from infertility treatment, mother had a previous cesarean delivery, number of previous c-sections, drug abuse, gonorrhea, syphilis, genital herpes, chlamydia, hepatitis C, Group B streptococcus, and HIV risk. We will also obtain data that indicate obstetric procedures performed during pregnancy or labor; characteristics of the process of labor including premature rupture of the membranes, precipitous or prolonged labor; induction of labor, augmentation of labor, non-vertex presentation, steroid treatment received by the mother prior to delivery, antibiotics received by the mother during labor, clinical chorioamnionitis diagnosed during labor or maternal temperature, moderate/heavy meconium staining of the amniotic fluid, fetal intolerance of labor such that one or more of the following actions was taken: in-utero resuscitative measures, further fetal assessment or operative delivery, epidural or spinal anesthesia during labor, none of the above, method of delivery, delivery with forceps attempted but unsuccessful, delivery with vacuum extraction attempted but unsuccessful, fetal presentation at birth (cephalic, breech, or other), final route and method of delivery, if cesarean, was a trial of labor attempted, and was cesarean needed to prevent disease transmission, i.e.: HIV, genital herpes, etc.; and maternal morbidity associated with labor and delivery, including maternal transfusion, third or fourth degree perineal laceration, ruptured uterus, unplanned hysterectomy, admission to intensive care unit, and unplanned operating room procedure following delivery.For infant health, we will obtain information on sex, race, infant birth and death dates, birth time, birth weights, types of birth defects, child transferred, hospital child transferred to, birth place, county of birth, child adopted, state and county of maternal residence, infant transferred to NICU, cause and related causes of death, method of delivery, plurality, multiple birth order, and 1-minute, 5-minute, and 10-minute APGAR scores, abnormal conditions of newborn, assisted ventilation required immediately following delivery, assisted ventilation required for more than six hours, NICU admission, newborn given surfactant replacement therapy, antibiotics received by the newborn for suspected neonatal sepsis, seizure or serious neurologic dysfunction, significant birth injury. We will obtain records of congenital anomalies of the newborns, including anencephaly, meningomyelocele/spina bifida, congenital heart disease, cyanotic congenital heart disease, congenital diaphragmatic hernia, omphalocele, gastroschisis, limb reduction defect, cleft lip with/without cleft palate, cleft palate alone, down's syndrome, suspected chromosomal disorder, hypospadias, or other anomalies. Other information related to infant health will include breast feeding and mother received WIC.For Objecitve (b): Accessibility to fresh fruits and vegetables will be assessed using the method described by McEntee and Agyeman (2010), primarily focusing on geographic access. We will use maternal residence point data that contain individual attribute information. Accessibility to food retail markets will be assessed by driving time or driving distance. The locations of retail stores and markets will be obtained from USDA NASS Michigan Field Office and other retail-store databases in the public domain.For data analysis, we will begin by estimating separate models for neonatal mortality, post-neonatal mortality, birth weights and birth defects that include only exposure to Superfund sites, providing a baseline for the relationship between the exposure and birth outcomes. We will then estimate models for birth outcomes that include the full set of explanatory variables. Using the geocodes, travel time between maternal residences and hospitals will be estimated, taking into account distance, road network density and driving speed limits (Wang 2006). In the analyses of neonatal and infant mortality, we will also include travel time to the nearest hospital with an infant intensive care unit, the type of the nearest hospital, whether there were hospital transfers before death, and location of death.Prior to regression analysis, the correlations among the explanatory variables will be examined. Preliminary multiple regression models will be constructed and evaluated before the appropriate models are selected to describe the relationship between the pregnancy outcomes and about the hypothesized predictor variables. Different analytical models will be constructed to demonstrate how the insufficient use of confounding variables, mismeasured exposure variables, and the lack of understanding of pathogenesis and etiology of diseases can distort association and causal effects.All births and deaths in the State of Michigan from 2000 to 2014 will be used in this study to maximize the quality of the estimates. Nationally, the prevalence of all birth defects is about 2% and infant mortality rate is approximately 0.68%. We will include as many births and deaths as possible to maximize the chance of finding associations with predictor variables, because infant mortality and birth defects previously reported to be associated with geographical factors are rare. Nonetheless, births and infant deaths of residences within 10 miles of the Michigan boarders will be excluded, because, having only Michigan information, we will not have sufficient information to estimate exposure in the vicinity that is outside of Michigan. For regression models that include 10 predictor variables in the analysis, using the expected sample size, we may be able to detect about 5-10% changes in infant mortality rate in multiple regression analyses, at the alpha level 0.03 and power of 0.8.For Objective (c): For assessing the human health risk of benzoic acid, we will adhere to the four steps of risk assessment: Hazard Identification, Toxicity Assessment, Exposure Assessment, and Risk Characterization, described in Risk Assessment in the Federal Government: Managing the Process, by National Research Council (1983) andScience and Decisions, by National Research Council (2009).