Reduction In Perinatal Mortality Research Articles

A Meta-Analysis of Low Dose Aspirin for the Prevention of Intrauterine Growth Retardation

Objective To determine more precisely the effect of prophylactic low dose aspirin on intrauterine growth retardation and perinatal mortality. Design Meta-analysis of 13 published randomised clinical trials. Methods We searched 18 medical databases, including MEDLINE since 1964 and EMBASE since 1974, review articles and the references from each retrieved report to identify all studies evaluating the effect of aspirin in pregnancy and including both intrauterine growth retardation and perinatal mortality as outcome measures. Results Among 13,234 women from 13 studies between 1985 and 1994, aspirin showed a significant reduction in intrauterine growth retardation (IUGR) (OR 0.82; 95% CI 0.72–0.93; P= 0.003) and a nonsignificant reduction in perinatal mortality (OR 0.84; 95% CI 0.66–1.08; P= 0.18). Subgroup analyses revealed that aspirin was effective at lower doses between 50 and 80 mg/day (IUGR: OR 0.87; 95% CI 0.76–0.99; mortality: OR 0.90, 95% CI 0.70–1.16), but that the preventive effect was greater at higher doses between 100 and 150 mg/day (IUGR: OR 0.36, 95% CI 0.22–0.59; mortality: OR 0.40, 95% CI 0.16–0.97) and among women entered before the 17th week of gestation (IUGR: OR 0.35, 95% CI 0.21–0.58; mortality: OR 0.43, 95% CI 0.17–1.06). We did not identify any specific subgroup of women most likely to benefit from aspirin treatment. Conclusion The results of this meta-analysis showed that early aspirin treatment reduced the risk of intrauterine growth retardation. Low dose aspirin should not be used routinely in pregnant women until those most likely to benefit from aspirin treatment have been clearly identified.

A meta-analysis of low dose aspirin for the prevention of intrauterine growth retardation.

To determine more precisely the effect of prophylactic low dose aspirin on intrauterine growth retardation and perinatal mortality. Meta-analysis of 13 published randomised clinical trials. We searched 18 medical databases, including MEDLINE since 1964 and EMBASE since 1974, review articles and the references from each retrieved report to identify all studies evaluating the effect of aspirin in pregnancy and including both intrauterine growth retardation and perinatal mortality as outcome measures. Among 13,234 women from 13 studies between 1985 and 1994, aspirin showed a significant reduction in intrauterine growth retardation (IUGR) (OR 0.82; 95% CI 0.72-0.93; P = 0.003) and a nonsignificant reduction in perinatal mortality (OR 0.84; 95% CI 0.66-1.08; P = 0.18). Subgroup analyses revealed that aspirin was effective at lower doses between 50 and 80 mg/day (IUGR: OR 0.87; 95% CI 0.76-0.99; mortality: OR 0.90, 95% CI 0.70-1.16), but that the preventive effect was greater at higher doses between 100 and 150 mg/day (IUGR: OR 0.36, 95% CI 0.22-0.59; mortality: OR 0.40, 95% CI 0.16-0.97) and among women entered before the 17th week of gestation (IUGR: OR 0.35, 95% CI 0.21-0.58; mortality: OR 0.43, 95% CI 0.17-1.06). We did not identify any specific subgroup of women most likely to benefit from aspirin treatment. The results of this meta-analysis showed that early aspirin treatment reduced the risk of intrauterine growth retardation. Low dose aspirin should not be used routinely in pregnant women until those most likely to benefit from aspirin treatment have been clearly identified.

Epidemiology of antepartum fetal testing

Advances in perinatal and neonatal health care over the past few decades have resulted in a substantial reduction in perinatal mortality. Some of this improvement has been attributed to antepartum fetal surveillance techniques. The primary objective of antepartum fetal surveillance techniques is to avoid fetal deaths. An ideal secondary objective is to avoid neonatal complications related to intrauterine asphyxia. In this article, some of the difficulties in evaluating existing antepartum fetal surveillance techniques are highlighted. Some of the epidemiological methods for evaluating a screening test are reviewed and their importance discussed with reference to fetal testing procedures. Lastly, the possibility of considering indication-specific fetal testing to improve perinatal morbidity is examined.

Computerized analysis of antepartum fetal heart rate tracings

For several decades, visual analysis of the antepartum fetal heart rate tracing has been a primary mode of fetal surveillance despite lack of proof from randomized trials that its use leads to a reduction in perinatal mortality in high risk pregnancies. A meta-analysis of these trials offered the same conclusion. The trials were performed in the early 1980's with fetal monitors with poor signal to noise ratios and poorer testing schemes in comparison to today. Therefore the results may no longer be pertinent, however, it is unlikely that these trials will be repeated because of present medico-legal constraints. Nonetheless, the use of non-stress testing alone is an accepted mode of fetal surveillance because of associated low fetal death rates within 1 week of a normal test; 1.9 to 3.2/1000 patients tested. The expense associated with this low fetal death rate is a low positive predictive value of 25% to 50%. Interrelated with this inefficiency, is the considerable inter- and intra-observer variation in the interpretation of antepartum fetal heart rate tracings. Variation in the interpretation of antepartum fetal heart rate tracings continues to exist despite the increase in experience and knowledge of fetal heart rate monitoring and improvement in fetal heart rate monitors. The end result is a form of fetal surveillance that is of questionable value and inefficient, requiring frequent back up testing to clarify fetal condition.

Cost-Effectiveness of One-Stage Ultrasound Screening in Pregnancy

The objective of this study was to evaluate, in a controlled clinical trial, the costs of standardized one-stage ultrasound screening in pregnancy in relation to the reduction in perinatal mortality. A trial population of 9310 pregnant women was randomly allocated to ultrasound screening or a control group. Two obstetric hospitals and 64 recruiting antenatal health centers were involved. The costs included actually realized costs, i.e. positive costs, and gains, i.e. negative costs, resulting from lower health-care use. Cost-accounting data were obtained by a questionnaire to all attenders and measurements at the screening, and later complemented by a questionnaire to a random sample of 534 screened women. Internal accounting and other hospital data, national statistics and health-market sources were also used. The actually realized cost of each avoided perinatal death was FIM 84 378 ($21 938), while the net over-all estimate combining all positive and negative costs showed a cost saving of FIM 65 680 ($17 077). The total positive unit cost of ultrasound screening was FIM 393 ($102). Longer ultrasound examination time and more numerous advanced examinations were rewarded by clearly fewer perinatal deaths and a better cost-effectiveness ratio. One-stage second-trimester ultrasound screening is cost-effective when all significant costs and effects are taken into account. Copyright © 1996 International Society of Ultrasound in Obstetrics and Gynecology

Induction of Labour: Post-term Pregnancy and Term Prelabour Rupture of the Membranes—Evidence for Practice

Post-term pregnancy and prelabour rupture of the membranes at term are two common clinical problems in obstetric practice. Appropriate management of these situations has been controversial, and has centred on the choice between induction of labour, its timing and method, and expectant management. We now have the benefit of results from two large randomized trials, one involving only Canadian centres (post-term pregnancy), and the other trial, coordinated in Canada and involving centres in Canada and five other countries (term prelabour rupture of the membranes) which should help guide practice in these two important areas. The Post-term Trial results showed that a policy of induction was associated with a lower Caesarean section rate than a policy of expectant management, with no differences in perinatal mortality or morbidity. When the results of this trial are combined with all other trials in a meta-analysis, a policy of induction is associated with a significant reduction in perinatal mortality. The recently completed international trial on prelabour rupture of the membranes (Term PROM) showed no differences in serious neonatal infection or Caesarean section rates between a policy of induction of labour and expectant management, but maternal infection was reduced in the induction/oxytocin arm of the trial, and women viewed a policy of induction more positively than expectant management.

Reduction of maternal and perinatal mortality in rural and peri-urban settings: what works?

The purpose of this article is two-fold: (i) to lay out conceptual frameworks for programming in the fields of maternal and neonatal health for the reduction of maternal and peri/neonatal mortality; (ii) to describe selected MotherCare demonstration projects in the first 5 years between 1989 and 1993 in Bolivia, Guatemala, Indonesia and Nigeria. In Inquisivi, Bolivia, Save the Children/Bolivia, worked with 50 women's groups in remote rural villages in the Andean mountains. Through a participatory research process, the ‘autodiagnosis’, actions identified by women's groups included among others: provision of family planning through a local non-governmental organization (NGO), training of community birth attendants, income generating projects. In Quetzaltenango, Guatemala, access was improved through training of traditional birth attendants (TBAs) in timely recognition and referral of pregnancy/delivery/neonatal complications, while quality of care in health facilities was improved through modifying health professionals' attitude towards TBAs and clients, and implementation of management protocols. In Indonesia, the University of Padjadjaran addressed issues of referral and emergency obstetric care in the West-Java subdistrict of Tanjunsari. Birthing homes with radios were established in ten of the 27 villages in the district, where trained nurse/midwives provided maternity care on a regular basis. In Nigeria professional midwives were trained in interpersonal communication and lifesaving obstetric skills, while referral hospitals were refurbished and equipped. While reduction in maternal mortality after such a short implementation period is difficult to demonstrate, all projects showed improvements in referral and in reduction in perinatal mortality.

The current status of Doppler sonography in obstetrics

Searches for clinical applications of Doppler ultrasound in fetomaternal medicine continue. Currently, there are three main areas of interest: Doppler velocimetry of the umbilical artery, uterine artery and the fetal circulation (cerebral and venous blood flow studies). Evidence from randomized trials suggests that if women with suspected intra-uterine growth retardation or pre-eclampsia are offered Doppler studies of the umbilical artery, a clinically important reduction in perinatal mortality may be expected. On the other hand, screening of low-risk women either by umbilical artery Doppler or uterine artery Doppler is unlikely to be cost-effective. The study of other fetal vessels provides a fascinating insight into vascular changes that occur in fetal compromise, but it is not known whether the use of these tests will actually reduce perinatal mortality and morbidity. None of the Doppler indices used so far, including the middle-cerebral artery to umbilical artery ratio, has been able to match the performance characteristics of umbilical artery Doppler. Until clear evidence emerges on its benefit or otherwise, comprehensive fetal assessment by Doppler ultrasound should be used for research purposes only and results of these tests should not be used to guide clinical practice.

Zur Qualität antepartaler Daten in der Hessischen Perinatalerhebung

In the Federal State of Hesse, Germany, pregnancy and delivery related data are collected in a central perinatal registry called "Hessische Perinatalerhebung" (HEPE) since 1981, the objective being to enforce quality assurance and to contribute to a reduction in perinatal mortality and morbidity. The delivery unit compiles these data based on the antenatal record called "Mother Passport" and the actual delivery. In order to check on the quality of data, information on risk factors obtained from the perinatal register was compared to information from antenatal records and from a questionnaire administered to pregnant women prior to delivery. The study population comprised 1978 women who delivered at the maternity unit of the Municipal Hospital of Wiesbaden, the Dr. Horst Schmidt Kliniken, in 1990 and 1991. Comparison of the three data sources revealed substantial differences: Almost all risk factors were most frequently mentioned by the mothers themselves, less by the antenatal record and even less by the perinatal register. These differences were less pronounced for data on previous pregnancies and pre-existing disease and on abnormal positioning. Considerable differences were found in relation to pregnancy induced hypertension, intra-uterine growth retardation, incapacity of the cervix, preterm labour and bleeding. Risk factors related to the social environment and personal habits like psycho-social stress and smoking were found to be extremely under-reported in the antenatal records as well as in the perinatal register. The following factors could be identified as major reasons for the different risk profiles obtained from the various data sources: [1] Data loss through the transfer of data from the antenatal record to the record form of the perinatal register or to the computer, [2] selective recording of those risk factors considered by doctors to be particularly relevant, [3] missing definition of some risk factors and [4] recording of antenatal data for the perinatal register by the delivery unit after knowing the pregnancy outcome. Antenatal data in the perinatal register of Hessen are doubtful and should not be used uncritically for comparative studies and the assessment of relative risks. The extreme under-reporting of some risk factors may even lead to giving some interventions undue priority. In future, regular validity studies should become routine. A reduction of the data losses as well as a clear separation of antenatal data and delivery data could be achieved if antenatal data would be transferred from the doctor providing antenatal care direct to the perinatal register.

Diagnostische und klinische Wertigkeit der Dopplersonographie in der Geburtshilfe

The diagnostic value (efficiency) of Doppler ultrasound in obstetrics is assessed by studying the association or correlation between Doppler measurement parameters and pregnancy outcome parameters, without influencing the clinical management. The clinical value (efficacy) is however assessed by studying the ability to improve the outcome of pregnancy if Doppler ultrasound is used in obstetrical management for the purpose of possible intervention. The accepted method for assessment of the diagnostic value is the observational study, and the best method for the assessment of the clinical value is the randomised controlled management study (clinical trial). Observational studies concerning the diagnostic value have been widely reported in the literature. According to these studies significant relationships between abnormal Doppler findings and the following obstetrical problems were found: intrauterine growth retardation, preterm delivery, acidosis determined by fetal blood sampling, abnormal intrapartum fetal heart rate, neonatal depression and acidosis, and admission to neonatal intensive care unit. However from these studies it cannot be concluded that pregnancy outcome will be improved by using this information clinically. This problem can only be properly addressed by appropriate clinical management studies. The majority of the published randomised controlled trials showed beneficial effect from Doppler ultrasound application in high-risk pregnancy management. These effects included a significant decrease in the duration of antenatal and neonatal hospital stay, the rate of labour induction, and the rate of emergency Caesarean section. At the same time there was no difference in the gestational age at delivery or in the total Caesarean section rate. None of these trials alone was large enough to demonstrate a statistically significant reduction in perinatal mortality. However cumulative meta-analysis allows pooling to evaluate the results from separate but similar studies. The results from such an analysis showed that in high-risk pregnancies managed with Doppler there is a significant decrease of 50 per cent in perinatal mortality and in stillbirths of anatomically normal fetuses. It is important to note that there was no increase in neonatal or maternal morbidity associated with the use of Doppler ultrasound, and that the reduction in perinatal mortality was not the result of a delay in timing fetal death.

The influence of socio-biological factors on perinatal mortality in a rural area of Bangladesh

"The present study considers data on all pregnancies that ended in a stillbirth or live birth in a rural area of Bangladesh during the years 1982 to 1984. It considers the relationships of both biological and socio-economic factors to perinatal mortality....[Results show a] lack of association with any measure of socio-economic status.... Our study has confirmed that survival of the perinatal period is separately related to both maternal age and primiparity. Once maternal age is taken into account, high parity shows no evidence of decreasing survival chances."

A randomized controlled trial on the clinical value of umbilical Doppler velocimetry in antenatal care

OBJECTIVE: Our aim was to assess the clinical value of umbilical Doppler velocimetry with regard to maternal hospitalization policy, obstetric management, and perinatal outcome. STUDY DESIGN: We conducted a randomized controlled trial in a university hospital population. A total of 1598 women participated, of whom 809 were allocated to the Doppler group and 789 to the control group. In the Doppler group umbilical Doppler studies were performed only when indicated. Abnormal pulsatility index values prompted intensified (clinical) fetal monitoring. In the control group Doppler velocimetry was not available. RESULTS: The use of umbilical Doppler velocimetry did not show any clinical or economical benefit with regard to maternal admission rate and duration or neonatal admission policy and requirements of ventilatory support. Neither did the use of Doppler have any beneficial effect on obstetric management during labor and the occurrence of fetal distress during labor. In the control group a higher perinatal mortality rate was observed. In the Doppler group the risk ratio of perinatal mortality of fetuses and infants weighing ≥500 gm was 0.45 (95% confidence interval 0.21 to 0.94), as compared with the control group. Neonatal mortality was equal in both groups; therefore the reduction in perinatal mortality was not the result of a delay in timing of fetal death. CONCLUSION: Selective use of umbilical Doppler velocimetry in pregnancies “at fetal risk” may be of benefit in antenatal care by a reduction of perinatal mortality and especially late fetal mortality. (AM J OBSTET GYNECOL 1994;170:625-34.)

Value of early glucose tolerance testing in women who had gestational diabetes in their previous pregnancy.

The patterns of glucose tolerance, clinical characteristics, and follow-up results of 1,027 pregnant women who had gestational diabetes diagnosed in their previous pregnancy, were analyzed. Glucose tolerance testing was performed before 24 weeks (mean 16.6 +/- 4.5 weeks) in 180 women (group 1); when the result was normal the test was repeated at 26-30 weeks' gestation. In this group the incidence of recurrent gestational diabetes was 49.4%, and early testing diagnosed 61.8% of cases. Group 2 consisted of 685 women in whom glucose tolerance was tested only at 26-30 weeks' gestation. In this group the incidence of recurrent gestational diabetes was 34.0%. Group 3 consisted of 162 women in whom glucose tolerance was not tested in the subsequent pregnancy. Perinatal mortality rates in Groups 1 to 3 were 2.2%, 0.6% and 3.1% respectively in the pregnancy subsequent to that in which gestational diabetes was first diagnosed. The risk of emerging diabetes mellitus on follow-up was greater in women in whom gestational diabetes was diagnosed early than in those diagnosed at the usual time (33.3% versus 12.5%, p < 0.05). Analysis of the 13 perinatal deaths in Groups 1-3 revealed 5 that were potentially avoidable; none of the 3 women with recurrent gestational diabetes in the early tested group who had perinatal deaths received insulin in their subsequent pregnancies. Although perinatal deaths are unavoidable in some high-risk pregnancies associated with gestational diabetes, this study suggests that early diagnosis of gestational diabetes may allow further reduction of perinatal mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

Perinatal mortality in a northern Nigerian rural community.

87 perinatal deaths which occurred out of 1484 births in a rural area of Northern Nigeria over a 9 month period were reviewed. The perinatal mortality rate was 58.6 per 1000 births. Babies born to very young adolescent mothers aged between 10-14 years had the highest perinatal mortality of 375 per 1000 births. Statistically significant relationships were also established between perinatal mortality and parity, educational status of the mother and birth weight. The leading cause of perinatal death was birth trauma which accounted for 48% of all perinatal deaths. Strategies for the reduction of perinatal mortality in the rural community are highlighted.

Hospital setting and fetal death during labor among women at low risk

Intrapartum fetal death in low-risk women at term is a rare obstetric outcome. This is difficult to study because few data sets contain an adequate number of cases for meaningful analysis. This study used data from the 1980 National Natality Survey and National Fetal Mortality Survey, merged with an American Hospital Association annual survey for the same year, to determine whether the frequency of intrapartum fetal death in low-risk women varied by the hospital setting for birth. Stratified analysis was used to assess the relation of level of hospital for delivery with intrapartum fetal death, with control for potential confounding factors. As the level of available perinatal technology decreased, the frequency of intrapartum fetal death increased (odds ratio, 2.0 for Level II and 3.3 for Level I, as compared with Level III hospitals). Even when early neonatal deaths were considered, perinatal mortality remained lowest at Level III facilities (odds ratio, 1.6 for Level II and 2.7 for Level I, as compared with Level III hospitals). The components of intrapartum surveillance that are most effective in the reduction of perinatal mortality have not been identified.

Perinatal Mortality in Shanghai: 1986–1987

The incidence of, and risk factors associated with, perinatal mortality in Shanghai during 1986-1987 are examined using data from a multi-site study conducted in 29 hospitals. The overall perinatal mortality rate was 14.96 per 1000 births. The mortality rates of antepartum fetal death, intrapartum fetal death and early neonatal death were 5.97, 2.06 and 6.94 per 1000 births, respectively. The perinatal mortality rates increased in winter and late spring. Male neonates were 1.5 times more likely to die than females. Low birthweight and preterm infants had 15 to 80 times higher risk of perinatal death. Higher parity, multiple pregnancy, and maternal age greater than or equal to 35 years were the risk factors for perinatal mortality. Asphyxia, cord complications, and congenital malformations were found to be the major causes of perinatal deaths. Comparison of mortality rates between Shanghai and the US suggests that the shortage of advanced technology in perinatal care (e.g. neonatal intensive care units) is a major obstacle to the reduction of perinatal mortality in Shanghai.

Effective Prevention of Preterm Birth: The French Experience Measured at Haguenau

In the late 1960s, a growing awareness of perinatal problems developed in France, focusing on the need to deal with handicaps of perinatal origin. A national program was proposed to address the combined goals of better care during pregnancy, delivery, and the first days of life. This program was funded for the period between 1971 and 1981. Preterm delivery was identified as playing an especially important role among the causes of perinatal handicaps. As early as 1969, Papiernik had published a coefficient of preterm delivery risk, which enumerated specific risks related to life-style and working conditions. Immediately prior to initiating the national program, it was proposed that the long-term effects of this program be assessed in an average maternity hospital. It was believed that if this program were to be effective, it would be possible on a local level to measure reductions in perinatal mortality as well as handicaps linked

Anteparfum Management of Twin Gestation

Twin gestation is now an area of vital concern to the perinatologist. Within the last decade a substantial reduction in perinatal mortality has been achieved, largely through advances in neonatal intensive care. However, preterm birth and its consequences remain the most important causes of perinatal morbidity and mortality. Twin pregnancy accounts for approximately 10% of all premature deliveries. From the data currently available, there is no justification for the routine use of hospital bedrest, prophylactic tocolytic agents, or elective cerclage in the management of twin pregnancy. Programs directed at the prevention of perterm delivery in twin pregnancy will be the focus of more scientific research. The use of ultrasound and antepartum testing in the form of the nonstress test, the biophysical profile, and Doppler ultrasound may lead to major advances in the diagnosis of intrauterine growth retardation and the twin-to-twin transfusion syndrome in twins. Therefore, it is reasonable to expect that fetal death and neonatal death from intrauterine growth retardation can be prevented.

Progestogen administration in pregnancy may prevent preterm delivery

Two recently published meta-analyses of controlled trials of a wide variety of progestational agents, used in pregnancy (Daya 1989; Goldstein et al. 1989), prompted this third meta-analysis of placebo-controlled trials involving the prophylactic use of a single agent, 17 alpha-hydroxyprogesterone caproate. Of seven relevant published reports of controlled trials, six had involved women considered to be a high risk of miscarriage or preterm birth. This analysis provides no support for the view that 17 alpha-hydroxyprogesterone caproate protects against miscarriage, but suggests that it does reduce the occurrence of preterm birth. The latter effect was reflected in a reduced rate of low birthweight babies, but not in a statistically significant reduction in perinatal mortality and morbidity. The difference between this meta-analysis and the two earlier meta-analyses illustrates the problems both of selective sub-grouping and of comprehensive pooling of data from small trials.

A model for the prospective analysis of perinatal deaths in a perinatal network

This prospective study assesses factors that contribute to perinatal mortality. The study population includes the 1362 perinatal deaths that occurred among 85,402 live births between 1983 and 1987 at hospitals of the University of Chicago Perinatal Network. After peer review of demographic, clinical, and pathologic data, each perinatal death was classified in one of the following categories: (1) the result of congenital malformation incompatible with life, (2) unavoidable, (3) potentially avoidable by patient, by health provider, or by both, or (4) of undetermined responsibility. Of 1362 deaths, 12.3% involved congenital malformations incompatible with life, 56.9% were classified as unavoidable, 28.1% were judged potentially avoidable, and 2.7% due to undetermined causes. Of potentially avoidable deaths, 36% were due to patient factors (primarily noncompliance), 59% to health provider factors, and 15% to combined patient and provider factors. There was a significant reduction in the potentially avoidable cases during the study period. The maximum attainable reduction in perinatal mortality under optimal conditions is calculated. Intervention plans to achieve this goal are discussed.