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Summary and Recommendations CBILDBIRrB TRENDS ARD STATISTICS Since the turn of the century the birthplace for children in the United States baa moved from the home to the hospital. Leas than 5 percent of the babies born in 1900 were delivered in a hospital. By 1940 the pro- portions bad shifted to about 50 percent in each location, and by 1979 hospital deliveries accounted for 99 percent of all births. Much of the impetus for the turnaround in selection of birth aitea waa provided by the application of expanding scientific and medical knowledge in the field of obstetrics, which led to improvements in techniques and changes of eapbaaia in maternity care. Beginning with a principal concern that the progress of labor and delivery be made safer for the mother, the medical aspects of obstetrics grew in importance. Later the concern for maternal welfare waa broadened to include better relief of pain during delivery, often by the administration of analgesic drugs and anesthesia. More recently, a significant reduction in the neonatal mortality rate baa resulted from improvements in maternal and pediatric care. Improvements in obstetrics have resulted in improved physical out- comes for mothers and babies. From 1955 to 1980 the maternal mortality rate declined from 47 to 7 deaths per 100,000 live births. Neonatal deaths in the aae period declined from 19.1 to 8.4 deaths per 1,000 live births. For a number of reaaona, social aa well aa medical, a new interest baa developed in the psychological factors surrounding the birth experi- ence. An increased interest in birth settings other than the conven- tional hospital one oriented toward treating disease and toward physi- cian management of patients baa also developed. The changing social context in which these childbirth interests are expressed includes the advent of the WOllen's movement, conaumeriam, a desire for a more natural delivery than that associated with medical intervention, and concern about rising health care coats. The effect of this baa been a reexamination of obstetrical practices. During the 1970a there waa rising concern that births were increas- ingly occurring in places other than hospitals. Accurate figures are not available, but it ia estimated that between 36,000 and 158,000 babies were delivered outside hospital settings in 1980. Births at home (both planned and unplanned) are now estimated to be about 1 percent of 2

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3 the total number of births per year, a percentage that has not in- creased, according to the National Center for Health Statistics. However, the number of freestanding birth centers grew from 3 in 1975 to about 130 now. Birth certificates and related recordkeeping do not usually contain the information necessary to indicate how many babies are delivered in each of the various birth locations. However, a few states (such as Oregon) do have accurate data. In Oregon 4.4 percent of the babies born in 1981 were not born in a hospital (see Appendix F). THE BIRTH SE'l"l'ING Factors contributing to the definition of a birth setting include the recipients of care, its locale, the providers of maternity care, and the practices of those providers. The well-being of mother and baby are the primary concern in any birth setting. Advocates of hospital births express concern for the availability of advanced technological care by skilled practitioners in the event of an untoward event during delivery. Advocates of nonhospital births emphasize the contributions toward maternal and neonatal well-being made by increased family sup- port and participation in the birth, minimal medical intervention, and lower costs. Maternity Care Providers Maternity care providers include physicians and a small number of cer- tified nurse midwives. The role and numbers of these two kinds of pro- viders have changed dramatically over the years. In 1910, •granny• lay midwives delivered 50 percent of babies: by 1979, midwives (primarily certified nurse midwives) delivered 1.6 percent. Physicians attended more and more births, delivering 98.1 percent of the babies in hospitals and 34.2 percent of those born elsewhere in 1979. Other health care personnel, such as naturopath& and chiropractors, deliver a very small percentage of babies. Some women, either by choice or circuastance, are not attended at birth by any professionally trained person. Providers of maternity care agree that identifiable high-risk pregnancies necessitate the use of specialists and advanced technology. There is less agreement on how to define and manage a noraal birth. These disagreements are exacerbated by a lack of adequate data on the effects of various maternity care practices. Delivery Sites The range of delivery sites includes the home, freestanding birth cen- ters, hospital-based birth centers, and conventional hospital maternity units. These sites vary as to the primary provider of care, use of technology, atmosphere, facilities, and proximity to emergency care. The variation within and among the different sites contributes to the complexity of conducting research in this area and to the difficulty of

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4 following clients across different locations for purposes of full and complete data collection. Birth Practices Maternity care practices have changed in recent years and appear to dif- fer in the various birth settings. For example, the frequency of induc- tion of labor rose from 8.6 percent of births in 1967 to 11.8 percent in 1977, and the rate of cesarean section rose from 7.3 percent in 1972 to 13.4 percent in 1977. Practices that are fairly uniform across the dif- ferent settings include prenatal care and patient education in child- birth and the care of infants. Practices more often sean in hospital settings include protocols and procedures related to the provision of care for high-risk mothers, fetuses, or infants. Practices more likely to be found in the nonhospital settings include participation of the family in prenatal care and at the birth, classes for siblings, and the decreased use of technology and medication during delivery. APPROACHES '1'0 RESEARCH AND STUDY DESIGNS The study committee's major task was to consider research designs for the evaluation of birth settings. Certain general approaches-- observational and experimental--for designing studies in scientific research were reviewed. Each would be useful in addressing different aspects of research of birth settings, depending on the scope of the investigation and the objectives of the study. The strengths and weak- nesses of several different designs and methods for data collection were identified and their use for assessing birth settings reviewed. Observational Approaches The committee believes that there is a lack of good descriptive studies on birth settings, especially alternative settings, and that well- conducted prospective descriptive and observational studies, even if without controls, could improve our understanding of the issues and be useful for generating hypotheses for further study. Experimental Designs Randomized Clinical Trials The committee determined that randomized clinical trials could be used to study many different techniques, or differences in the birth attendants, in similar birth settings. In the past such trials have been conducted on birth settings to exaaine the effects of such variables as the position of the mother during delivery, the presence of a supportive lay person during delivery, and the use or nonuse of electronic fetal monitoring. Randomization among sites may not be generally possible, because women choosing to deliver at one

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s site, or their care providers, may not be willing to be randomly as- signed to a different site. However, there may be situations when such randomization is possible--for example, when a woman is of a divided mind or open to randomization to a site offering an approach to child- birth that is similar to that of her original choice. Prospective Matched Groups Nonrandomized designs are likely to be pro- posed by researchers studying the impact of alternative birth settings. Although randomized experiments are most desirable for interpreting causal relationships, prospective studies using rigorously matched groups delivering in different settings may provide useful information about the safety and psychological benefits of alternative settings. For example, comparisons could be made among women who have selected particular birth settings, such as a freestanding birth center, a birth room in a hospital, or a tertiary care hospital. Various types of data could be collected before and after the birth. Comparisons could be made of mortality, morbidity, and various psychosocial measures, includ- ing anxiety, satisfaction with the care received, mother-infant bonding, and the like. The moat obvious problem with this design is the possi- bility that any differences among the groups can be attributed to selec- tion of different sites by mothers with different characteristics. Regardless of how well the study is planned, this problem may not be overcome. Despite this limitation, however, the committee believes that prospective studies would provide much-needed information on the spec- trum of birth settings. Cooperative Registries A possible way to collect data with which to evaluate different birth settings is to organize groups of hospital and nonhospital birth centers to collect uniform information on each birth at a central data-collection center. Both hospital and nonhoapital set- tings could be chosen so as to represent the major points along the spectrum of birth settings in the United States. The data set should include important prognostic factors so that subsets within the popula- tion of mothers and infanta could be properly compared. A cooperative registry could eventually result in a data base useful for answering questions on quantitative aspects of birth practices, especially ones that occur very rarely. This would be a major and very expensive under- taking similar to the collaborative perinatal project of the National Institute of Neurological and Comaunicative Disorders and Stroke (NINCDS) that studied 50,000 pregnancies at 12 different institutions. Surveillance Methods The greatest utility of surveillance methods has been for situations in which the presence of a single adverse event, for example, the death of a mother during delivery, mandates a chain of public health activities, including review of the case to determine ita preventability. Special studies often are added to routine data col- lection to exaaine the specific circumstances surrounding a maternal death. Similar types of studies could also be used to evaluate dif- ferent birth settings.

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6 The routine recording of births and deaths by all SO states could serve as a useful starting point for analysis of the risks to mother and infant as mediated by place of delivery and provider. In most reporting areas in the United States, docu.entation of low birth weight or preterm gestation is possible with reasonable accuracy. In some reporting areas, low Apgar scores and ca.plications of pregnancy and labor are re- corded. Although not all of these events can be regarded as avoidable, their presence in a planned nonhospital delivery may reflect a failure of the risk assessment screening process. Identified adverse events could be reviewed by a panel of experts to determine the degree of their preventability. Considerable experience has been accumulated in this method of assessment by committees established in every state to inves- tigate the cause of maternal mortality. The disadvantage of surveillance is that data currently available fro. vital records do not give specific information on intended place of delivery, actual place of delivery, and birth attendant(&). The coaaittee recom.ends that such data be recorded on all birth certifi- cates. case-Control Studies If counts of the denominator populations are not available, and if events to be studied occur infrequently, one recourse is to match adverse events with control births free of adverse outcomes and investigate the circuastances of the pregnancy. Por example, if planned nonhospital deliveries are found more frequently among cases of adverse events than .-eng oontrols, this can be taken as evidence for a differential effect of place of delivery on the adverse event. A retro- spective approach is more likely to have confounding elements than the preferred prospective approach, however, and questions will always re- main. Never·theless, a case-control approach may be one of the least costly ways to gain infor.ation about very rare events. RISK ASSESSMENT Any comparisons of birth settings will need to be carried out carefully because women who deliver in different sites may differ in aany charac- teristics. Por this reason characteristics of the study population will need to be carefully described by researchers and any differences con- trolled for in the study design or analysis. Differences in levels of risk ..ong the women result fro. the screening process used to increase the likelihood of a normal delivery in a nonhospital setting. women delivering in a freestanding birth center will have to be compared with similar low-risk individuals delivering in the hospital. WO..n who select different settings are also likely to differ with respect to demographic and psychological variables. Therefore, the researcher must direct special attention to assessing psychological variables to assure similarity ..ong groups. The screening process for determining the potential for complica- tions to develop during pregnancy, delivery, or the neonatal period is called obstetric risk assessment. An understanding of obstetric risk

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7 assessment ia essential for conducting research on childbirth settings. Risk status ia aaaeaaed through a scoring ayatea that assigns pregnan- cies to various levels of probability of outco.eJ tbia measurement of risk provides a probability statement with an error rate. Attempts to t.prove the precision of obstetric risk measurement are aimed at reduc- ing the rate of error. Moat of the existing risk assessment instruments used for screening pregnant women are baaed on prediction of perinatal mortality or mor- bidity. Variables ccaaon to moat instruments are demographic and socio- economic and variables baaed on past pregnancies, past medical history, and present pregnancy. In some of the more recent studies, fetal heart rate and uterine contraction data from electronic monitoring have been included. Purther development of risk aaaeaaaent aetboda ia needed to make thea more useful for predicting maternal outcomes and perinatal morbidity and for research on birth settings. Approximately 20 percent of women predicted to be at low risk experience co.plicationa that re- quire transfer to a hospital setting during pregnancy or delivery. Approximately 14 percent of women aaaeaaed ineligible for delivery in a low-risk setting experience no complications. Selection of Variables Investigators should provide detailed atateaenta of bow variables are defined and used in their studies. Fetal, neonatal, and maternal deaths occur now with leas frequency than in previous decades and can no longer be taken aa the sole measure of quality of care. Morbidity ia becoming a more frequent aeaaure of pregnancy outcome. Interest baa shifted to studying the effects of maternal and perinatal care on such morbidity indices aa neurological deficits, developmental problema, and satisfac- tion with the birth experience. T.berefore, outcome measures must be defined for these indices, including the quality of bonding established between parents and infantJ •parenting• abilityJ and the eiDOtional, intellectual, and physical development of the infant. T.be comaittee concluded that more research ia needed to define outcome measures other than mortality that can be accurately aeaaured for studying birth practices. RECOMMENDATIONS T.be comaittee concludes that reliable information about the safety and efficacy of different birth settings (see Appendix A), the psychologi- cal benefits of different practices (see Appendix D), and the differ- ences in economic costa of the alternatives (see Appendix B) ia lack- ing. Rigorous data will proaote informed debate and policy development by advocates of the various settings. Honetheleaa, the c~ittee recog- nizes that many values surround childbirth and that iaauea and arguments will continue regardless of research and new information. Although it realized the difficulty of doing research on this topic, the committee identified several approaches that could begin to generate

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8 information. The comaittee'a observations and recom.endations are as follows a • Research into the safety and efficacy of the various birth set- tings has high priority. Recomaended research designs or methods for collecting data (described in detail in Chapter 2) include randa.ized clinical trials wherever possible to study different techniques or methods used in aiailar birth aettingaJ prospective aatched group or cohort studies of low-risk women delivering in different settings, in- tensive surveillance methods--for example, surveillance of live births and their complications--together with special data collection and methods of evaluating adverse event&J and a registry to collect data useful for evaluating maternity care in a number of different institu- tions and in different settings. Specific recoaaendations or caveats about research on birth settings are given in Chapters 2 1 3 1 and 4 of this volume. • Lack of data has been a aajor i~iment to research in the evaluation of birth settings. Government agencies responsible for de- signing birth and fetal death certificates should include space for routine recording of the intended and actual site of delivery (e.g., conventional hospital delivery rooa or alternative birth roo., free- standing birth center, planned hoae delivery, accidental nonhoapital delivery) and the precise type of provider (board-certified or certifi- cate-eligible obstetrician, general or faaily practitioner, certified nurse midwife, midwife with no special training, other individual). Births in freestanding birth centers should not be described as occur- ring in a hospital. These data will enable investigators to deteraine the numbers of births planned in different settings, to analyze trends in the choice of birthplaces, and to identify the health care provider. Linked to mortality and morbidity data, this inforaation will be especi- ally valuable for studying birth settings. • Risk assessment of patients is crucial in deteraining research population eligibility for delivery in an alternative setting. Moat existing risk assessment inatru.enta can predict that a low-risk preg- nancy will not result in a perinatal death. More than 98 percent of pregnant women labeled as low risk will have live infants at the end of the neonatal period. These instruments are leas accurate for predicting neonatal morbidity. Therefore, a number of women and their infanta will need to be transferred to a hospital during labor and delivery. Research to perfect and extend the reliability of risk aaaea...nt methods is desirable because accurate screening will ainiaize the need to transfer .other and child before, during, or after delivery (see Appendix E). • The lack of sound empirical data about the psychological bene- fits of one or another birth setting makes it difficult for potential parents and physicians to choose the one moat appropriate. Appendix D of this report reviews the literature on aoae of the psychological as- pects of birth and raises methodological issues for consideration by researchers. Priorities in this area are studies of differences in developmental outco.ea of the child and parent-child relationships ac-

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9 cording to birth settings. Does one setting foster a closer relation- ship between parent and child than another? • Because of the range of settings and the breadth of questions to be answered, the ca.aittee urges a aultidiaciplinary approach and the for.ation of multidisciplinary teams for research on birth settings. A good research prograa will require a variety of investigators to as- sure valid screening and selection of a study population and ca.petent handling of the range of settings and the flow of patients across a aya- tea of care. Experts in research design should be a part of such an effort.