Contribution of late fetal deaths to US perinatal mortality rates, 1995-1998

We analyzed US fetal death and linked infant birth-death certificate data for 1995-1998 to evaluate perinatal deaths (late fetal deaths [> or = 28 weeks' gestation] and early neonatal deaths [< or = 7 days of life]) by race, Hispanic ethnicity, state of residence, and selected demographic characteristics. We also compared components of perinatal mortality, late fetal deaths, and early neonatal deaths, by birthweight, gestational age, and selected maternal medical conditions during pregnancy. From 1995 through 1998, there were 221,767 fetal deaths at > or = 20 weeks' gestation and infant deaths at less than 1 year. Of these, 113,421 (51%) were perinatal deaths; late fetal deaths accounted for 47% of perinatal deaths. The total perinatal mortality rate declined 5.3%, from 7.5 to 7.1 per 1,000 live births plus late fetal deaths. Blacks experienced higher perinatal mortality rates than whites (rate ratio = 2.1). Among perinatal deaths > or = 28 weeks' gestation, the ratio of fetal to neonatal deaths was 3.4 among blacks and 2.4 among whites. State-specific rates ranged from 5.2 to 13.1 per 1,000 live births plus late fetal deaths. Although late fetal deaths are not included in routine statistics of pregnancy outcomes, these deaths represent a large proportion of adverse pregnancy outcomes. Surveillance of perinatal mortality provides a more complete picture of the health of women, fetuses, and newborns. Improving the quality of surveillance data regarding fetal deaths is essential for more effective use of these data. This information can be used to prevent excess perinatal deaths and reduce disparities in pregnancy outcomes among high-risk subgroups identified by individual and population characteristics.     

Birth Centers in Australia: A National Population‐Based Study of Perinatal Mortality Associated with Giving Birth in a Birth Center

ABSTRACT: Background: Perinatal mortality is a rare outcome among babies born at term in developed countries after normal uncomplicated pregnancies; consequently, the numbers involved in large databases of routinely collected statistics provide a meaningful evaluation of these uncommon events. The National Perinatal Data Collection records the place of birth and information on the outcomes of pregnancy and childbirth for all women who give birth each year in Australia. Our objective was to describe the perinatal mortality associated with giving birth in “alongside hospital” birth centers in Australia during 1999 to 2002 using nationally collected data. Methods: This population‐based study included all 1,001,249 women who gave birth in Australia during 1999 to 2002. Of these women, 21,800 (2.18%) gave birth in a birth center. Selected perinatal outcomes (including stillbirths and neonatal deaths) were described for the 4‐year study period separately for first‐time mothers and for women having a second or subsequent birth. A further comparison was made between deaths of low‐risk term babies born in hospitals compared with deaths of term babies born in birth centers. Results: The total perinatal death rate attributed to birth centers was significantly lower than that attributed to hospitals (1.51/1,000 vs 10.03/1,000). The perinatal mortality rate among term births to primiparas in birth centers compared with term births among low‐risk primiparas in hospitals was 1.4 versus 1.9 per 1,000; the perinatal mortality rate among term births to multiparas in birth centers compared with term births among low‐risk multiparas in hospitals was 0.6 versus 1.6 per 1,000. Conclusions: This study using Australian national data showed that the overall rate of perinatal mortality was lower in alongside hospital birth centers than in hospitals irrespective of the mother’s parity. (BIRTH 34:3 September 2007)     

When Do Perinatal Deaths in Multiple Pregnancies Occur?

Perinatal mortality for multiple pregnancy remains at least 5 times the rate for singleton births. The major causes are neonatal deaths due to gross immaturity before 30 weeks' gestation, and stillbirths due to intrauterine growth retardation at all gestations, but especially after 32 weeks. Sixty four per cent of perinatal losses before 30 weeks' gestation occur before 26 weeks, highlighting the need to commence prophylactic measures earlier than usually recommended. The perinatal mortality in infants in multiple births weighing more than 2,500g is the same as that of singletons, but is 10 times this rate in multiple births weighing between 500g and 2,500g. Because the stillbirth rate in twins proceeding beyond 38 weeks' gestation is 3 times that of singleton births, elective termination of pregnancy is recommended if spontaneous labour has not occurred by this time.     

Perinatal Mortality in a Tertiary Obstetric Institution

At the Royal Women's Hospital, Melbourne in the 3 years 1987-1989 analysis of the records of 13,347 public patients revealed an overall perinatal wastage of 20.8 per 1,000 births. This seemingly high figure resulted from the fact that 45% of losses occurred in nonbooked and emergency admissions. Many patients were referred with major complications of pregnancy, especially gross prematurity, lethal congenital malformations and intrauterine deaths. During the 3-year period 74% of perinatal losses occurred before 33 weeks' gestation and only 10% were after 37 weeks. By comparison at a Victorian State level, 47% of perinatal deaths occurred before 33 weeks and more than 35% after 37 weeks' gestation. The major causes of perinatal wastage in both groups were similar. At the Royal Women's Hospital in the 3-year period lethal congenital abnormalities accounted for 19.1% of fetal wastage, premature labour, premature rupture of the membranes and cervical incompetence 16.2%, multiple pregnancy 14.7%, antepartum haemorrhage 14.0% and hypertensive disorders 9.7%. During the 3-year period 7.7% of hospital stillbirths were intrapartum compared to 27% for the State of Victoria. The stillbirth rate in Victoria has declined over the past decade, but to a lesser extent than the neonatal death rate. Over the 3-year period 1987-1989 the ratio of stillbirths to neonatal deaths was 3 to 2, and in 1989 there were nearly twice as many stillbirths as neonatal deaths (424 versus 240). Furthermore, 55% of stillborn infants in Victoria had birth-weights of more than 1,500 g compared to the Royal Women's Hospital figure of 36%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Management and outcome of pregnancy in diabetes mellitus, classes B to R

During the period 1971 to 1975, 260 women with diabetes mellitus, Classes B through R, were delivered of their infants at Los Angeles County Women's Hospital. The plan of patient management included frequent clinic visits and hospitalization to assure good control. A program of intensive antepartum fetal surveillance was begun at 34 weeks' gestation, with the use of daily 24 hour urinary estriol determinations and a weekly contraction stress test (CST). A lecithin/sphingomyelin ratio was evaluated for all patients before elective delivery. The perinatal mortality rate in these diabetic pregnant women was 46 per 1,000 as compared to 24 per 1,000 in the general population. Only three stillbirths occurred in the diabetic group, none within one week of a negative CST. Congenital malformations were responsible for almost half of the neonatal deaths. There were no deaths due to iatrogenic prematurity or trauma. Mean gestational age at delivery was 37.9 weeks and vaginal delivery was the mode for approximately half of the women. Two thirds of the infants did experience some morbidity.     

Perinatal mortality at King Fahd Hospital of the University Al-Khobar, Saudi Arabia

The perinatal deaths of all singleton births that occurred at King Fahd Hospital of the University, Al-Khobar, Saudi Arabia during a 4-year period are analysed. The causes of death are classified into 12 groups using an extended modification of the Aberdeen classification. There were 165 perinatal deaths in 8057 singleton births, giving a perinatal mortality rate of 20.47 per 1000 total births. Fetal malformations occurred in 29 (17.57%) cases. Of the remaining 136 normal infants, 77 (56.6%) were stillbirths and 59 (43.4%) died within 1 week of delivery. Spontaneous premature labor was the commonest cause of death (23.52%) followed by birth trauma (11%) and maternal diseases (9.55%). The cause of death was not known in 22 (16.17%) cases. In conclusion, prevention of premature labor, better intrapartum fetal monitoring, early recognition of fetal distress and improvement of neonatal care should reduce the perinatal mortality rate.     

Regional population-based study on pregnancy outcomes in women with diabetes mellitus in Japan

AIM: We compared pregnancy outcomes in diabetic women with the background population in Miyazaki, Japan. METHODS: In 1998, we started the regional, population-based, peer-review conference to investigate the possible causes of perinatal deaths. For this purpose, at least one obstetrician and one neonatologist congregated from each institution (one tertiary and five secondary perinatal centers). A retrospective, population-based study was conducted in a total of 53 862 deliveries during 1999-2003. Among them, there were 248 perinatal deaths including six deaths in association with diabetes mellitus (DM). The number of diabetic pregnancies was estimated to be 381 during the study period. Perinatal mortality was compared between the diabetic women and background population by chi2-test. RESULTS: The perinatal mortality rate in diabetic women was 15.7 per 1000 deliveries, which was compared with 4.6 per 1000 in the background population (P = 0.003; odds ratio: 3.5; 95% confidence interval: 1.5-7.9). Four of the six perinatal deaths in diabetes were sudden intrauterine demises after 37 weeks' gestation, and the others were neonatal deaths of congenital heart anomaly or extreme prematurity. Most deaths were attributable to either undiagnosed or insufficient perinatal management. CONCLUSIONS: In an unselected population in Japan, diabetic women have 3.5 times the reported risk of perinatal mortality of the general population. Further improvements in the diagnosis and management of DM during pregnancy are required.     

Induction of labour, birthweight and perinatal mortality by day of the week

There were 66,974 births at the three largest Dublin maternity hospitals in the years 1980-1982. Data on numbers of spontaneous and elective births, birthweight and perinatal mortality were analysed by day of the week. Perinatal mortality rates were highest on Wednesdays and Saturdays. The rate on Sunday was close to average. The largest number of perinatal deaths per day occurred on Wednesdays and the smallest on Sundays. Significant variations in mortality rates and percentage low birthweight were found among the 19% of infants who were born electively, but not among those born after a spontaneous onset of labour. High-risk pregnancies, including many with intra-uterine fetal death, were induced in large numbers from Tuesdays through Saturdays with a peak on Wednesdays. Low risk cases were induced mainly from Monday through Fridays with a peak on Fridays. The pattern of perinatal mortality through the week followed closely that of the risk status of pregnancies delivered electively. The results indicate that the pattern of perinatal mortality by day of the week of birth was determined by a highly organized weekly routine of selective elective delivery.     

Impact of infants born at the threshold of viability on the neonatal mortality rate in Colorado.

OBJECTIVE: To determine the contribution of infants born at the threshold of viability (< 750 gm) on neonatal mortality in Colorado. STUDY DESIGN: For the period of January 1991 to December 1996, all Colorado live births who expired were evaluated for gestational age, birth weight, gender, hospital level of care, age at time of death, delivery room resuscitation, mechanical ventilation, medical and surgical complications, and serious malformations. RESULTS: Although infants weighing < 750 gm represent only 0.31% of all live births, they account for 46.3% of deaths. While those infants weighing < 500 gm and with a gestation of < 24 weeks almost always died (94.7%), the majority born in the 500- to 745-gm category (55.8%) survived. The vast majority (88.5%) of deaths occurred on the first day of life. A total of 38.4% of births in which the infant weighed < 750 gm occurred outside bona fide regional perinatal centers. CONCLUSION: Future attempts to reduce the Colorado neonatal mortality rate would best focus on the 500- to 750-gm weight group through the re-regionalization of high-risk perinatal care.     

Neonatal outcomes and quality of care in level II perinatal centers supported by a children's hospital-medical school level III program.

OBJECTIVE: Eight Level II perinatal centers developed contracts with the children's hospital to provide consultative neonatal patient care, education, and administrative support. The purpose of the present study was to evaluate infant outcomes and quality of care during a 3-year period of the program, 1994 to 1996. STUDY DESIGN: Neonatal mortality rates were determined for the 18,703 live births. Quality of care was assessed for 30 infants who died at the Level II centers and 315 infants transferred to the children's hospital. RESULTS: The neonatal mortality rate was 2.2/1000 live births. Quality-of-care issues primarily involved 80 "drop-in" deliveries 相似文献   

The impact of prenatal care on neonatal deaths in the presence and absence of antenatal high-risk conditions

OBJECTIVE: The purpose of this study was to determine the association between prenatal care in the United States and the neonatal death rate in the presence and absence of antenatal high-risk conditions. STUDY DESIGN: Data were derived from the national perinatal mortality data sets for the years 1995 through 1997, which were provided by the National Center for Health Statistics. Analyses were restricted to singleton live births that occurred after 23 completed weeks of gestation. Multivariable logistic regression analyses were used to adjust for the presence or absence of various antenatal high-risk conditions, maternal age, gestational age at delivery, and birth weight. RESULTS: Of 10,530,608 singleton live births, 18,339 (1.7/1000 births) resulted in neonatal death. Neonatal death rates (per 1000 live births) were higher for African American infants compared with white infants in the presence (2.7 vs 1.5, respectively) and absence (10.7 vs 7.9, respectively) of prenatal care. Lack of prenatal care was associated with an increase in neonatal deaths, which was greater for infants born at > or =36 weeks of gestation (relative risk, 2.1; 95% CI, 1.8, 2.4). Lack of prenatal care was also associated with increased neonatal death rates in the presence of preterm premature rupture of the membranes (relative risk, 1.3; 95% CI, 1.1, 1.5), placenta previa (relative risk, 1.9; 95% CI, 1.2, 2.9), fetal growth restriction (relative risk, 1.7; 95% CI, 1.2, 1.6), and postterm pregnancy (relative risk, 1.4; 95% CI, 1.0, 2.9). CONCLUSION: In the United States, prenatal care is associated with fewer neonatal deaths in black and white infants. This beneficial effect was more pronounced for births that occurred at > or =36 weeks of gestation and in the presence of preterm premature rupture of the membranes, placenta previa, fetal growth restriction, and postterm pregnancy.     

Causes and consequences of recent increases in preterm birth among twins.

OBJECTIVE: To examine the causes and consequences of the recent increase in preterm birth among twins. METHODS: We studied all twin births among residents of the province of Nova Scotia, Canada, between 1988 and 1997. Rates of preterm birth, preterm labor induction, preterm cesarean, small-for-gestational age (SGA), respiratory distress syndrome (RDS), stillbirth, perinatal mortality, and infant mortality were compared between past and more recent years. Changes in perinatal mortality were examined using logistic regression to adjust for the effects of other determinants. RESULTS: The study included 2516 twin births (73 stillbirths and 2443 live births). The rate of preterm birth increased from 42.3% in 1988-1992 to 48.2% of twin live births in 1993-1997 (14% increase, P =.04). Twin live births born after preterm labor induction increased from 3.5% in 1988-1989 to 8.6% in 1996-1997 (P for trend =.007). Of live births between 34 and 36 weeks' gestation, the proportion born SGA decreased from 17.5% in 1988-1992 to 9.2% in 1993-1997 (P =.005). Over the same period, rates of prophylactic maternal steroid therapy increased substantially and rates of RDS declined. Perinatal mortality rates among pregnancies reaching 34 weeks decreased from 12.9 per 1000 total births in 1988-1992 to 4.2 per 1000 total births in 1993-1997 (P =.05). CONCLUSION: Increases in preterm labor induction appear to be responsible for the recent increase in preterm birth among twins. These changes have been accompanied by decreases in perinatal morbidity and mortality among twin pregnancies that reach 34 weeks' gestation.     

Wessex Perinatal Mortality Survey 1982

Summary. A survey of 335 perinatal deaths in the Wessex region revealed a perinatal mortality rate of 10·1 per 1000 total births. Lethal malformations accounted for 82 (24%) deaths. Of the 253 normally formed infants, 124 (49%) died during pregnancy and 33 (13%) in labour. More than 60% of the stillbirths weighed >1500 g. Of the 96 postpartum deaths, half occurred within 24 h of delivery, mostly following complications of labour and circumstances suggesting hypoxia. The Aberdeen classification showed half of the mothers had pregnancy complications: other predisposing factors were identified in 10% of perinatal deaths. There were 185 neonatal deaths of which 150 occurred within 7 days and 35 within the next 3 weeks. Sixteen (46%) of the late neonatal deaths were due to a congenital abnormality; pregnancy or labour complications were present in six (32%) of the remaining 19 normally formed infants. Review of existing methods of antenatal supervision in particular, followed by the use of better monitoring systems for earlier detection of fetal distress and prompt action when indicated, together with improvement in neonatal care in the first 24 h after birth should further reduce the perinatal mortality.     

Wessex perinatal mortality survey 1982

A survey of 335 perinatal deaths in the Wessex region revealed a perinatal mortality rate of 10.1 per 1000 total births. Lethal malformations accounted for 82 (24%) deaths. Of the 253 normally formed infants, 124 (49%) died during pregnancy and 33 (13%) in labour. More than 60% of the stillbirths weighed greater than 1500 g. Of the 96 postpartum deaths, half occurred within 24 h of delivery, mostly following complications of labour and circumstances suggesting hypoxia. The Aberdeen classification showed half of the mothers had pregnancy complications: other predisposing factors were identified in 10% of perinatal deaths. There were 185 neonatal deaths of which 150 occurred within 7 days and 35 within the next 3 weeks. Sixteen (46%) of the late neonatal deaths were due to a congenital abnormality; pregnancy or labour complications were present in six (32%) of the remaining 19 normally formed infants. Review of existing methods of antenatal supervision in particular, followed by the use of better monitoring systems for earlier detection of fetal distress and prompt action when indicated, together with improvement in neonatal care in the first 24 h after birth should further reduce the perinatal mortality.     

Total perinatal wastage. A clarification of priorities

The pregnancy outcome of 16,971 women carrying 17,352 living fetuses after 16 weeks gestation was studied. As well as recording perinatal deaths, all losses before 28 weeks and up to one year after delivery were recorded to give a total perinatal wastage rate of 21.6 per 1000 fetuses alive at 16 weeks compared with a perinatal mortality rate (stillbirths plus early neonatal deaths) of 7.8 per 1000 births. All deaths were then classified according to pathological sub-groups. The concept of auditing perinatal care using perinatal mortality was then compared with that using total perinatal wastage.     

Analysis of perinatal mortality at a teaching hospital in Dar es Salaam, Tanzania, 1999-2003

We conducted a retrospective analysis of perinatal mortality at Muhimbili National Hospital (MNH), Dar es Salaam, Tanzania 1999-2003 in order to categorise/classify perinatal deaths as well as to identify key factors in perinatal care that could be improved. Data were retrieved from the MNH obstetric database and causes of early neonatal deaths were traced from the neonatal ward register. The study includes all foetuses weighing =500g. A modified Nordic-Baltic classification was used for classification of perinatal deaths. Over a 5-year period there were 77,815 babies born with a perinatal mortality rate of 124 per 1000 births, 78% of which was labour related stillbirth. The PMR was 913/1000 for singleton births and 723/1000 for multiple births for babies weighing less than 1500 grams and 65/1000 for singleton births and 116/1000 for multiple births for babies weighing 2500 grams or more. Babies weighing less than 1500 grams contributed 26% of PMR, whereas 41% occurred in babies weighing 2500 grams or more. The majority (79%) of neonatal deaths had Apgar score <7 at 5 minutes and the most common causes of neonatal mortality were birth asphyxia (37%) and prematurity (29%). Labour related deaths were more common in multiple pregnancies. The majority of the perinatal deaths should be essentially avoidable through improved quality of intrapartum care. Establishment of perinatal audit at MNH can help identify key actions for improved care.     

Determinants of perinatal mortality in Nigeria

Objective

To determine risk factors for perinatal mortality among hospital-based deliveries in Nigeria.

Methods

The WHO Global Maternal and Perinatal Health Survey was implemented in Nigeria as a first step in establishing a global system for monitoring maternal and perinatal health. Twenty-one health facilities with more than 1000 deliveries annually were selected by a stratified multistage cluster sampling strategy. Information was recorded on all women who delivered and their neonates within a 3-month period.

Results

Overall, there were 9208 deliveries, comprising 8526 live births, 369 fresh stillbirths, 282 macerated stillbirths, 70 early neonatal deaths, and 721 perinatal deaths. The stillbirth and perinatal mortality rates were, respectively, 71 and 78 per 1000 deliveries; the early neonatal death rate was 8 per 1000 live births. Approximately 10% of all newborns weighed less than 2500 g, and 12.3% were born at less than 37 weeks of gestation. Predictors of perinatal mortality were mother's age, lack of prenatal care, unbooked status, prematurity, and birth asphyxia.

Conclusion

The perinatal mortality rate remains unacceptably high in Nigeria. Fresh stillbirth accounted for most perinatal deaths. Interventions to improve the utilization and quality of prenatal care, in addition to the quality of intrapartum care, would considerably reduce perinatal death.     

Umbilical artery flow velocity waveforms and twin pregnancy outcome

Two hundred seventy-two twin pregnancies were studied by analysis of the fetal umbilical artery waveforms recorded using continuous-wave Doppler ultrasound. After the first 100 cases, a management strategy was adopted whereby all twin gestations would be studied between 28-32 weeks' gestation and the results made available to the referring obstetrician, thereby influencing clinical management. Perinatal mortality and morbidity, in pregnancies with both fetuses alive at 28 weeks' gestation, were compared between the patients studied in the first group of 100 and those studied after the Doppler examination was introduced as a clinical service. There was a decrease in perinatal mortality, both uncorrected (57.9 per 1000 to 17.9 per 1000; P less than .05) and corrected (42.1 per 1000 to 8.9 per 1000). Fetal deaths were reduced from six to one (P less than .05). This decrease in perinatal mortality was achieved without any appreciable change in the gestational age at delivery or mode of delivery between the two groups. There was a reduction in the number of infants requiring neonatal intensive care (from 38% to 24%; P less than .01).     

Falling incidence of hypoxic-ischaemic encephalopathy in term infants.

OBJECTIVE: To examine trends in the incidence of hypoxic-ischaemic encephalopathy over a 13-year period. DESIGN: A retrospective analysis of medical records of all infants admitted in the years 1976-1980 and 1984-1988. SETTING: A large non-teaching district health authority in central England. SUBJECTS: Infants admitted to a district general hospital neonatal unit with clinical features of hypoxic-ischaemic encephalopathy. MAIN OUTCOME MEASURES: Incidence of three grades of hypoxic-ischaemic encephalopathy, handicap and mortality. RESULTS: During the first 5-year period the overall incidence of hypoxic-ischaemic encephalopathy was 7.7 per 1000 live births with 2.6 per 1000 live births being severely affected (grades II and III). In the second 5-year period the overall incidence was 4.6 per 1000 live births with 1.8 per 1000 live births being severely affected. The difference in the overall rate is statistically significant. Of the infants with severe encephalopathy 61% had Apgar scores below 4 at 1 min and 60% were born by instrumental or operative delivery. CONCLUSIONS: The fall in incidence of hypoxic-ischaemic encephalopathy has occurred during a period of falling perinatal mortality rate. It was instructive to find that infants born vaginally and without obstetric intervention formed a larger fraction of the severely affected infants in the later period.     

Total perinatal wastage. A clarification of priorities

Summary. The pregrmncy outcome of 16 971 women carrying 17 352 living fetuses after 16 weeks gestation was studied. As well as recording perinatal deaths, all losses before 28 weeks and up to one year after delivery were recorded to give a total perinatal wastage rate of 21.6 per 1000 fetuses alive at 16 weeks compared with a perinatal mortality rate (stillbirths plus early neonatal deaths) of 7.8 per 1000 births. All deaths were then classified according to pathological sub-groups. The concept of auditing perinatal care using perinatal mortality was then compared with that using total perinatal wastage.