A new method to examine very low birth weight fetal and hebdomadal mortality in a regionalized system of perinatal care

OBJECTIVE

Aggressive maternal transport of very low birth weight (VLBW) live births from community hospitals to regional perinatal centers may artificially increase community fetal death rates. By allocating maternal transports according to the location of antepartum and intrapartum care and separately computing antepartum and intrapartum fetal mortality rates, a more appropriate measure of hospital-based mortality may be determined.

METHOD

Delivery charts were reviewed for 568 VLBW deliveries (including 97 fetal deaths and 77 hebdomadal deaths) occurring between 1990 and 1992 in a geographically defined perinatal region. Maternal transports were analyzed with community hospitals for antepartum mortality rates and with the regional center for intrapartum mortality rates.

RESULTS

Using traditional methods, the fetal mortality rates for community hospitals and the regional center were antepartum 385.1 vs. 45.2, respectively, and intrapartum 120.9 vs. 24.9, respectively. When regional center live births (maternal transports) are placed with community hospitals for analysis of antepartum mortality, the new antepartum mortality rates were 185.7 vs. 72.8, respectively. The hebdomadal mortality rate for community hospitals was 250.0 as compared to 145.8 for the regional center.

CONCLUSION

Maternal transports to a regional center represent successful antepartum management by community care providers. Even though they delivered in the regional center, they should be analyzed with community hospitals for antepartum fetal mortality comparisons. Therefore, antepartum and intrapartum fetal mortality should be examined separately in a functioning regionalized perinatal care program where the location of patient care differs from location of delivery.

The association between adequacy of prenatal care utilization and subsequent pediatric care utilization in the United States

OBJECTIVE

To explore the association between adequacy of prenatal care utilization and subsequent pediatric care utilization.

DESIGN

A longitudinal follow-up of a nationally representative sample of infants born in 1988.

PARTICIPANTS

Nine thousand four hundred forty women who had a live birth in 1988, and whose child was alive at the time of interview, and 8285 women from the original sample who were reinterviewed in 1991.

MAIN OUTCOME MEASURE

There were four outcome measures: number of well-child visits; adequate immunization for diphtheria, tetanus, and pertussis; adequate immunization for polio; and continuity of a regular source of care, as measured by the number of sites for pediatric care.

RESULTS

Children whose mothers had less than adequate prenatal care utilization had significantly fewer well-child visits, and were significantly less likely to have adequate immunizations, even after income, health insurance coverage, content of prenatal care, wantedness of child, sites of prenatal and pediatric care, and maternal and pregnancy risk characteristics were taken into account. Less than adequate prenatal care utilization was not associated with having more than one pediatric care site.

CONCLUSIONS

Prenatal care utilization can be used to identify and target interventions to women who are at risk for not obtaining well-child care or complete immunizations for their children.

Influence of diabetes during pregnancy on gestational age-specific newborn weight among US black and US white infants

This study examined the impact of maternal diabetes on birth weight for gestational age patterns of all term black infants and white infants in the United States using data derived from the 1990-1991 US Live Birth File of the National Center for Health Statistics. Infants of both black mothers and white mothers exhibited the expected fetal overgrowth associated with maternal diabetes. However, the increase in birth weight was much greater in infants of black than white diabetic mothers in comparison with their nondiabetic counterparts, as measured by the discrepancy in birth weight between infants of diabetic and nondiabetic mothers at each gestational week, the incidence of large for gestational age, high birth weight, small for gestational age, and low birth weight. After adjustment for maternal hypertension, prenatal care use, and sociodemographic factors, the disparity in mean birth weight associated with diabetes was 211.67 g in black infants and 115.74 g in white infants. The adjusted odds ratios of birth weight > or = 4,000 g were 2.98 (95% confidence interval 2.89-3.12) for black infants and 1.83 (95% confidence interval 1.78-1.89) for white infants. Given the potential risks for mothers and infants consequent to maternal diabetes and fetal hyperinsulinemia, further investigation of the prevalence, characteristics, and outcomes of diabetes during pregnancy among black mothers and infants is warranted.

The changing pattern of prenatal care utilization in the United States, 1981-1995, using different prenatal care indices

CONTEXT

Two measures traditionally used to examine adequacy of prenatal care indicate that prenatal care utilization remained unchanged through the 1980s and only began to rise slightly in the 1990s. In recent years, new measures have been developed that include a category for women who receive more than the recommended amount of care (intensive utilization).

OBJECTIVE

To compare the older and newer indices in the monitoring of prenatal care trends in the United States from 1981 to 1995, for the overall population and for selected subpopulations. Second, to examine factors associated with receiving intensive utilization.

DESIGN

Cross-sectional and trend analysis of national birth records.

SETTING

The United States.

SUBJECTS

All live births between 1981 and 1995 (N=54 million).

MAIN OUTCOME MEASURES

Trends in prenatal care utilization, according to 4 indices (the older indices: the Institute of Medicine Index and the trimester that care began, and the newer indices: the R-GINDEX and the Adequacy of Prenatal Care Utilization Index). Multiple logistic regression was used to assess the risk of intensive prenatal care use in 1981 and 1995.

RESULTS

The newer indices showed a steadily increasing trend toward more prenatal care use throughout the study period (R-GINDEX, intensive or adequate use, 32.7% in 1981 to 47.1 % in 1995; the Adequacy of Prenatal Care Utilization Index, intensive use, 18.4% in 1981 to 28.8% in 1995), especially for intensive utilization. Women having a multiple birth were much more likely to have had intensive utilization in 1995 compared with 1981 (R-GINDEX, 22.8% vs 8.5%). Teenagers were more likely to begin care later than adults, but similar proportions of teens and adults had intensive utilization. Intensive use among low-risk women also increased steadily each year. Factors associated with a greater likelihood of receiving intensive use in 1981 and 1995 were having a multiple birth, primiparity, being married, and maternal age of 35 years or older.

CONCLUSIONS

The proportion of women who began care early and received at least the recommended number of visits increased between 1981 and 1995. This change was undetected by more traditional prenatal care indices. These increases have cost and practice implications and suggest a paradox since previous studies have shown that rates of preterm delivery and low birth weight did not improve during this time.

Ethnic-specific predictors of prenatal care utilisation in Hawaii

The state of Hawaii has had near-universal health insurance coverage for the last 20 years. Its highly diverse population offers the opportunity for a unique, natural experiment in the United States on the examination of social differences in health care utilisation when financial barriers are removed. Therefore, the objective of this study is to examine predictors of prenatal care utilisation patterns in the four major ethnic groups in Hawaii. The data used in this study are the 1979-92 Hawaii livebirth vital record files. A total of 165,301 singleton livebirths to Hawaii-resident mothers of Caucasian, native Hawaiian, Japanese or Filipino ancestry were selected. Despite near-universal health care coverage in Hawaii, a surprising number of women did not adequately utilise prenatal care, with large differences between groups. Multivariate analyses indicated that similar maternal socio-demographic factors were associated with prenatal care use in each ethnic group. Social variation continues to exist among all ethnic groups even in the presence of universal access to care. These data emphasise the need to address the distinct cultural needs of populations for providing health services, and further challenge the assumption that removal of financial barriers will ensure a high level of prenatal care use.

Prenatal care utilization in Hawaii: did it improve during the last 16 years?

This paper examines the utilization of prenatal care in Hawaii from 1979 to 1994 to determine if early and adequate utilization of prenatal care has changed during this period. Birth certificates of single live born infants of resident women were the source of data for the study. During the study period, the proportion of women receiving prenatal care in the first trimester increased by nearly 5 percent but was still below the national and state Year 2000 health objective of 90 percent. Notwithstanding this improvement, the percentage of women who did not receive the recommended number of visits in spite of starting care early significantly increased. The overall proportion of women with 'intensive' prenatal care use markedly increased (134.7%). The proportion of women with 'inadequate' care use declined (10.3%), although the proportion of women with 'no care' use doubled. Complete reporting of use of care through birth certificates markedly deteriorated. The findings of this study indicate the need for changes in the targeting and provision of counseling and education on the part of health care providers. Public health leaders, policy makers, health care providers, and advocacy groups need to collectively review programmatic directions with an aim toward the development of innovative approaches to address the emerging health needs of mothers and infants in the state.

An assessment of the use and impact of ancillary prenatal care services to Medicaid women in managed care

OBJECTIVES

Managed care plans under Medicaid are becoming a usual source of care for low-income pregnant women. This study describes an ancillary prenatal care service intervention developed by one managed care organization (MCO) for Medicaid-enrolled women, assesses the extent to which the intervention services were used, and appraises the influence of the intervention on prenatal care participation.

METHOD

There were 226 intervention and 258 control women with a single live birth delivered between 28 and 44 weeks gestation who (1) were enrolled in the MCO's Medicaid program, (2) were high-risk based on a prenatal risk assessment, and (3) started prenatal care prior to 26 weeks gestation. Less than adequate and intensive prenatal care utilization were chosen as intervention outcomes measures.

RESULTS

Family planning, a 2-month postpartum baby visit, a maternal postpartum visit, and a WIC (Special Supplemental Nutrition Program for Women, Infants, and Children) referral were among the most self-selected intervention services for this population; home health aide and breast-feeding support were the least requested services. Over 90% of those needing family planning or breast-feeding services received the services, while over 20% of the intervention group refused child care, food assistance and family violence referrals, and home health aide and smoking cessation services. The intervention group had a significantly lower risk of less than adequate utilization of prenatal care (OR = .32; 95% CI: 0.17-0.60) and was more likely to have an intensive number of prenatal care visits (OR = 1.61; 95% CI: 1.05-2.48).

CONCLUSIONS

The ability of managed care organizations to provide ongoing prenatal care to Medicaid populations in a cost-effective manner depends partly on their development of packages of prenatal services that foster positive preventive health care utilization behaviors and good pregnancy outcomes. The results of this project suggest that the intervention was beneficial in the area of improving utilization of prenatal care.

Parental factors influencing patterns of prenatal care utilization

OBJECTIVES

The objectives of this study are to examine the influence of paternal and maternal education and marital status on the initiation and adequate use of prenatal care services.

METHODS

Data were obtained from the 1990-1991 Minnesota Live Birth file. Single live births to white resident mothers who were 21 years of age or older were selected for investigation. After these selections 102,798 cases were analyzed.

RESULTS

Logistic regression was used to examine the association of parental characteristics on the following three measures of poor prenatal care use: (1) receiving no prenatal care; (2) initiating care later than the first trimester; and (3) given a first trimester start of care, receiving less than the recommended number of prenatal care visits. Within each maternal education stratum, an increased risk of delayed initiation and less efficient use of prenatal care were observed for lower paternal educational attainment. Unmarried women, regardless of educational level, exhibited more than a tenfold risk of receiving no prenatal care, and unmarried women of low educational attainment exhibited the highest risk of delayed care.

CONCLUSIONS

A persistent positive effect of increasing paternal education on the level of adequacy of prenatal care utilization within all maternal marital status and educational attainment groups poses further challenges to our understanding of the factors that influence prenatal care use.

Temporal trends in maternal characteristics and pregnancy outcomes: their relevance to the provision of health services. Hawaii, 1979-1994

This paper examines changes in maternal sociodemographic characteristics and pregnancy outcomes in Hawaii during the period 1979-1994. The more striking changes were increases of 129% in the proportion of births to women > 35 years old and of 67% in the proportion of births to unmarried mothers. The percentage of low birth weight and small-for-gestational age infants decreased while the proportion of premature births increased. Identified changes were not limited to selected population groups, but were found in various degrees in all ethnic groups. These findings are relevant to all health practitioners and will assist in the provision of appropriate care and counseling to individual women.

After graduation, what? An analysis of the job placements of graduates of public health maternal and child health training programs. Project of the Association of Teachers of Maternal and Child Health

OBJECTIVES

In 1995, the Association of Teachers of Maternal and Child Health (ATMCH) decided that information about the employment status of program graduates was essential to attempts to improve MCH curricula.

METHOD

ATMCH requested information from 13 MCH programs in schools of public health funded by the federal Maternal and Child Health Bureau and 12 provided information about their master's degree graduates in the 1990-1994 period, including the year of graduation, degree, Bureau traineeship support, position held, and employing agency.

RESULTS

The total number of graduates was 742. Four programs averaged less than 8 graduates per year (small); six, 10-16 (midsize); and two more than 22 (large). More than 90% of graduates received a M.P.H. In the 10 programs that provided data on Bureau support, 46% received traineeship support from the Bureau. Midsize programs had the largest percentage of graduates receiving traineeship support. Overall, 45% of graduates were in administrative positions, 32% were involved in patient care, 20% were in policy-analytic positions, and 3% in other positions. Forty-seven percent of program graduates entered into or continued in community-based agencies, 18% in government agencies, 17% in academic or research agencies, and 18% in other agencies. Program size was significantly associated with both position and the agency in which the graduate was employed. Bureau traineeship support was associated with employing agency.

CONCLUSIONS

The study suggests the need for changes in MCH curricula, enhanced education opportunities in specialty skill areas, and an ongoing survey of graduates of MCH programs.

The influence of site of care on the content of prenatal care for low-income women

OBJECTIVE

To assess whether site of prenatal care influences the content of prenatal care for low-income women.

DESIGN

Bivariate and logistic analyses of prenatal care content for low-income women provided at five different types of care sites (private offices, HMOs, publicly funded clinics, hospital clinics, and other sites of care), controlling for sociodemographic, behavioral, and maternal health characteristics.

PARTICIPANTS

A sample of 3405 low-income women selected from a nationally representative sample of 9953 women surveyed by the National Maternal and Infant Health Survey, who had singleton live births in 1988, had some prenatal care (PNC), Medicaid participation, or a family income less than $12,000/year.

OUTCOME MEASURES

Maternal report of seven initial PNC procedures (individually and combined), six areas of PNC advice (individually and combined), and participation in the Women Infant Children (WIC) nutrition program.

RESULTS

The content of PNC provided for low-income women does not meet the recommendations of the U.S. Public Health Service, and varies by site of delivery. Low-income women in publicly funded clinics (health departments and community health centers) report receiving more total initial PNC procedures and total PNC advice and have greater participation in the WIC program than similar women receiving PNC in private offices.

CONCLUSIONS

Publicly funded sites of care appear to provide more comprehensive prenatal care services than private office settings. Health care systems reforms which assume equality of care across all sites, or which limit services to restricted sites, may foster unequal access to comprehensive PNC.

Using motor milestones as a multistep process to screen preterm infants for cerebral palsy

Pediatricians often informally use motor milestones to screen infant motor development, and one advantage is that they can be used during sequential office visits, as a multistep screening process. In this study we evaluated six motor milestones (roll prone to supine, roll supine to prone, sit with support, sit without support, crawl and cruise) as a multistep process in screening for cerebral palsy in 173 high-risk preterm infants (<33 weeks gestational age) who had been followed with sequential developmental assessments for at least 18 months. At the 18 to 24 month evaluation, 31 (18%) had cerebral palsy. We found that using the motor milestones as serial screening tests for cerebral palsy was more effective in terms of positive predictive value than any individual milestone alone. Limited community resources can be more efficiently used if preterm infants with delays in more than four motor milestones are referred for further evaluation and early intervention services.

Pregnancy outcomes of US-born and foreign-born Japanese Americans

OBJECTIVES

This study investigated the birth outcomes of Japanese Americans, focusing on the role of the mother's place of birth.

METHODS

Single live births to US-resident Japanese American mothers (n = 37,941) were selected from the 1983 through 1987 US linked live birth-infant death files.

RESULTS

US-born mothers were more likely than foreign-born mothers to be less than 18 years old and not married, to start prenatal care early, and to more adequately use prenatal care. Infants of foreign-born Japanese Americans had a slightly lower risk of low birthweight.No significant differences were found between nativity groups for very low birthweight or neonatal, postneonatal, and infant mortality. The mortality rates of infants of US-born (6.2) and foreign-born (5.4) Japanese American women were below the US Year 2000 objective but still exceeded Japan's 1990 rate (4.6). However, low-birthweight percentages of the US-born group (5.7%) and the foreign-born group (5.0%) were similar to that of Japan (5.5%).

CONCLUSIONS

The infants of foreign-born Japanese-American women exhibited modestly better low-birthweight percentages than those of US-born Japanese Americans. This finding supports theories of the healthy immigrant.

A United States national reference for fetal growth

OBJECTIVE

To develop a current national fetal growth curve that can be used as a common reference point by researchers to facilitate investigations of the predictors and consequences of small and large for gestational age delivery.

METHODS

Single live births to United States resident mothers in 1991 (n = 3,134,879) were used for the development of this curve, which was compared with four previously published fetal growth curves. Techniques were developed to address cases with implausible birth weight-gestational age combinations and to smooth fetal growth curves across gestational age categories.

RESULTS

In general, the previously published fetal growth curves underestimated the 1991 United States reference curve. This underestimation is most apparent during the latter weeks of gestation, approximately 33-38 weeks.

CONCLUSION

Our findings indicate that the prevalence of fetal growth restriction (FGR) will vary markedly, depending on the fetal growth curve used. Furthermore, many previously published fetal growth curves no longer provide an up-to-date reference for describing the distribution of birth weight by gestational age and for determining FGR that is consistent with the most recent live birth data for the entire United States.

Conceptualization, measurement, and use of gestational age. I. Clinical and public health practice

Despite its importance for both clinical and public health practice and the considerable effort spent during the past three decades to develop alternative estimation methods, the measurement of gestational age on both the individual and population level continues to be problematic. The availability of alternative approaches for the estimation of gestational age has to some extent obscured the basic differences in the conceptualization of these measures and influenced our current state of thinking about gestational age. As the evidence grows that these alternative gestational age estimation measures do not precisely correspond with one another, controversies have arisen regarding which method is most accurate. In the search for a single gestational age "gold standard," the potentially valuable information that these alternative measures may provide when used in combination should not be overlooked.

The effect of gaps in health insurance on continuity of a regular source of care among preschool-aged children in the United States

OBJECTIVE

To estimate the prevalence and length of gaps in health insurance coverage and their effect on having a regular source of care in a national sample of preschool-aged children.

DESIGN

Follow-up survey of a nationally representative sample of 3-year-old children in the US population by phone or personal interview.

PARTICIPANTS

A total of 8129 children whose mothers were interviewed for the 1991 longitudinal Follow-up to the National Maternal and infant Health Survey.

MAIN OUTCOME MEASURES

Report of any gap in health insurance for the children, the length of the gap, and the number of different sites where the children were taken for medical care as a measure of continuity of a regular source of care.

RESULTS

About one quarter of Us children were without health insurance for at least 1 month during their first 3 years of life. Over half of these children had a health insurance gap of more than 6 months. Less than half of US children had only one site of care during their first 3 years. Children with health insurance gaps of longer than 6 months were at increased risk of having more than one care site (odds ratio = 1.52; 95% confidence interval, 1.19 to 1.96). This risk further increased when an emergency treatment was discounted as a multiple site of care.

CONCLUSIONS

Having a gap in health insurance coverage is an important determinant for not having a regular source of care for preschool-aged children. This finding is of concern, given the sizable percentage of children in the United States who lacked continuous health care coverage during a critical period of development.

Adolescent parity and infant mortality, Minnesota, 1980 through 1988

The association of parity and infant mortality was studied using linked birth-death files for 46,985 infants born to 11- to 19-year-old Minnesota residents between 1980 and 1988. Compared with infants of primiparas, infants of multiparas were at twice the risk for infant and postneonatal death but at no increased risk for neonatal death. They were also at two to three times the risk for deaths due to accidents, infections, and sudden infant death syndrome. The higher sociodemographic disadvantage and poorer prenatal care of multiparas did not explain the excess infant mortality risk that was concentrated in causes of death that are potentially preventable through primary care and parent education.

Pregnancy outcomes of Pacific islanders in Hawaii

Percentages of low birth weight are low in American Indian and Mexican-American populations despite a high prevalence of traditional risk factors. Data derived from 1979-1990 Hawaii vital record files were used to examine birth weight, infant mortality, and their correlates in Samoan and Hawaiian residents of Hawaii to assess whether traditional risk factors are adequate predictors of low birth weight and whether low birth weight is an adequate measure of infant mortality risk in Polynesian populations. Despite very low educational attainment, high proportions of unmarried status, and inadequate prenatal care use, low and very low birth weight percentages were less than the US average. High birth weight was common. Unmarried status and primiparity after age 17 increased low birth weight risk, while high educational attainment and Samoan ethnicity decreased the risk. Adequate prenatal care was not associated with reduced low birth weight risk. Higher than expected neonatal mortality, particularly among normal birth weight infants, and high postneonatal mortality among Hawaiian infants suggest that poverty and maternal chronic disease, rather than low birth weight, may be the primary mediators of infant mortality risk in some populations. The need for clearer specification of risk factors and caution in generalized risk assessment in diverse populations is emphasized.