Home births in England and Wales, 1979: perinatal mortality according to intended place of delivery.

A survey was carried out of all 8856 births occurring at home in England and Wales in 1979. Of these births, 67% had been booked for delivery at home, 21% had been booked for delivery in hospital, 3% had not been booked, and for 9% the intended place of delivery was unknown. The perinatal mortality varied almost 50-fold according to the intended place of delivery, ranging from 4.1/1000 births in those booked for delivery at home to 196.6/1000 unbooked births. Deliveries that occurred at home but had been booked for a hospital consultant unit were associated with a perinatal mortality of 67.5/1000. Births that had been booked for delivery at home included the smallest proportion of babies of low birth weight: 2.5% weighed 2500 g or less compared with 18% of those booked for consultant units and 29% of those not booked. Within these low birthweight groups there were noticeable differences in perinatal mortality; births booked to occur at home had the lowest mortality and unbooked births had the highest. Perinatal mortality among babies who weighed more than 2500 g was generally low irrespective of the intended place of delivery; the only exception was in babies whose delivery had not been booked. In all groups perinatal mortality was considerably higher in nulliparous than parous women. Women booking a delivery at home are clearly a selected group, and some may have been transferred to hospital during labour and were thus not included in the survey. Nevertheless, these data suggest that the perinatal mortality among births booked to occur at home is low, especially for parous women.     

Reproductive pattern,perinatal mortality,and sex preference in rural Tamil Nadu,south India: community based,cross sectional study.

OBJECTIVES: To study reproductive pattern and perinatal mortality in rural Tamil Nadu, South India. DESIGN: Community based, cross sectional questionnaire study of 30 randomly selected areas served by health subcentres. SETTING: Rural parts of Salem District, Tamil Nadu, South India. SUBJECTS: 1321 women and their offspring delivered in the 6 months before the interview. MAIN OUTCOME MEASURES: Number of pregnancies, pregnancy outcome, spacing of pregnancies, sex of offspring, perinatal and neonatal mortality rates. RESULTS: 41% of the women (535) were primiparous; 7 women (0.5%) were grand multiparous (> 6 births). The women had a mean age of 22 years and a mean of 2.3 pregnancies and 1.8 live children. The sex ratio at birth of the index children was 107 boys per 100 girls. The stillbirth rate was 13.5/1000 births, the neonatal mortality rate was 35.3/1000, and the perinatal mortality rate was 42.0/1000. Girls had an excess neonatal mortality (rate ratio 3.42%; 95% confidence interval 1.68 to 6.98; this was most pronounced among girls born to multiparous women with no living sons (rate ratio 15.48 (2.04 to 177.73) v 1.87 (0.63 to 5.58) in multiparous women with at least one son alive). CONCLUSIONS: In this rural part of Tamil Nadu, women had a controlled reproductive pattern. The excess neonatal mortality among girls constitutes about one third of the perinatal mortality rate. It seems to be linked to a preference for sons and should therefore be addressed through a holistic societal approach rather than through specific healthcare measures.     

The accident at Chernobyl and outcome of pregnancy in Finland.

OBJECTIVE--To evaluate the outcome of pregnancy in Finnish women after the accident at the Chernobyl nuclear power plant on 26 April 1986. DESIGN--Geographic and temporal cohort study. SETTING--Finland divided into three zones according to amount of radioactive fallout. SUBJECTS--All children who were exposed to radiation during their fetal development. Children born before any effects of the accident could be postulated--that is, between 1 January 1984 and 30 June 1986--served as controls. INTERVENTIONS--Children were divided into three temporal groups: controls, children who were expected to be born in August to December 1986, and children who were expected to be born in February to December 1987. They were also divided, separately, into three groups according to the three geographic zones. END POINT--Incidence of congenital malformations, preterm births, and perinatal deaths. MEASUREMENTS AND MAIN RESULTS--There were no significant differences in the incidence of malformations or perinatal deaths among the three temporal and three geographic groups. A significant increase in preterm births occurred among children who were exposed to radiation during the first trimester whose mothers lived in zones 2 and 3, where the external dose rate and estimated surface activity of caesium-137 were highest. CONCLUSIONS--The results suggest that the amount of radioactive fallout that Finnish people were exposed to after the accident at Chernobyl was not high enough to cause fetal damage in children born at term. The higher incidence of premature births among malformed children in the most heavily polluted areas, however, remains unexplained.     

Collaborative survey of perinatal loss in planned and unplanned home births. Northern Region Perinatal Mortality Survey Coordinating Group.

OBJECTIVE: To document the outcome of planned and unplanned births outside hospital. DESIGN: Confidential review of every pregnancy ending in stillbirth or neonatal death in which plans had been made for home delivery, irrespective of where delivery eventually occurred. The review was part of a sustained collaborative survey of all perinatal deaths. SETTING: Northern Regional Health Authority area. SUBJECTS: All 558,691 registered births to women normally resident in the former Northern Regional Health Authority area during 1981-94. MAIN OUTCOME MEASURE: Perinatal death. RESULTS: The estimated perinatal mortality during 1981-94 among women booked for a home birth was 14 deaths in 2888 births. This was less than half that among all women in the region. Only three of the 14 women delivered outside hospital. Independent review suggested that two of the 14 deaths might have been averted by different management. Both births occurred in hospital, and in only one was management before admission of the mother judged inappropriate. Perinatal loss to the 64 women who booked for hospital delivery but delivered outside and to the 67 women who delivered outside hospital without ever making arrangements to receive professional care during labour accounted for the high perinatal mortality (134 deaths in 3466 deliveries) among all births outside hospital. CONCLUSIONS: The perinatal hazard associated with planned home birth in the few women who exercised this option (< 1%) was low and mostly unavoidable. Health authorities purchasing maternity care need to address the much greater hazard associated with unplanned delivery outside hospital.     

Perinatal mortality and morbidity among babies delivered in water: surveillance study and postal survey

AimTo compare perinatal morbidity and mortality for babies delivered in water with rates for babies delivered conventionally (not in water).DesignSurveillance study (of all consultant paediatricians) and postal survey (of all NHS maternity units).SettingBritish Isles (surveillance study); England and Wales (postal survey).SubjectsBabies born in the British Isles between April 1994 and March 1996 who died perinatally or were admitted for special care within 48 hours of birth after delivery in water or after labour in water followed by conventional delivery (surveillance study); babies delivered in water in England and Wales in the same period (postal survey).Results4032 deliveries (0.6% of all deliveries) in England and Wales occurred in water. Perinatal mortality was 1.2/1000 (95% confidence interval 0.4 to 2.9) live births; 8.4/1000 (5.8 to 11.8) live births were admitted for special care. No deaths were directly attributable to delivery in water, but 2 admissions were for water aspiration. UK reports of mortality and special care admission rates for babies of women considered to be at low risk of complications during delivery who delivered conventionally ranged from 0.8/1000 (0.2 to 4.2) to 4.6/1000 (0.1 to 25) live births and from 9.2 (1.1 to 33) to 64/1000 (58 to 70) live births respectively. Compared with regional data for low risk, spontaneous, normal vaginal deliveries at term, the relative risk for perinatal mortality associated with delivery in water was 0.9 (99% confidence interval 0.2 to 3.6).ConclusionsPerinatal mortality is not substantially higher among babies delivered in water than among those born to low risk women who delivered conventionally. The data are compatible with a small increase or decrease in perinatal mortality for babies delivered in water.

Key messages

• Data on adverse effects of delivery in water have been limited
• Perinatal mortality and risk of admission for special care is similar for babies delivered in water and for low risk deliveries that do not take place in water
• The risk of perinatal mortality for babies delivered in water is similar to the risk for babies born by normal vaginal delivery to women at low risk of adverse outcome
• Delivery in water may have caused water aspiration in two babies and contributed to snapped umbilical cord in five

     

Perinatal mortality rates in isolated general practitioner maternity units.

OBJECTIVE--To determine the perinatal mortality rate among normally formed, singleton babies with birth weights greater than or equal to 2500 g in Bath health district based on the intended place of delivery at the time of onset of labour or at the time of diagnosis of intrauterine death. DESIGN--The numbers of live births and stillbirths were collected monthly returns from the maternity units concerned. Deaths of infants aged less than or equal to 1 week were collected in the same returns. The intended place of delivery was confirmed at the monthly perinatal mortality meeting, during which maternal and fetal factors were discussed. SETTING--A rural health district of 400,000 population where one third of all deliveries occurred in seven isolated general practitioner maternity units, 8% in the integrated general practitioner unit, and the remainder in the consultant unit. SUBJECTS--All babies of women whose deliveries were booked in the district before the onset of labour or the diagnosis of intrauterine death, excluding twins, babies with lethal congenital malformations, and those less than 2500 g. MAIN OUTCOME MEASURES--Outcome of all deliveries and parity of mothers. RESULTS--14,415 Deliveries were analysed. The perinatal mortality rate was 2.8/1000 births in the consultant unit (7950 deliveries), 4.8 in the isolated general practitioner units (5237 deliveries), and zero in the integrated general practitioner unit (1228 deliveries). Perinatal deaths attributable to asphyxia were more common in the isolated general practitioner units (1.5 per 1000) than the consultant unit (0.6 per 1000). The perinatal mortality rate among babies born to nulliparous women was 3.2/1000 births in the consultant unit and 5.7 in the isolated general practitioner units; for those born to multigravid women it was 2.4 and 4.2 respectively. CONCLUSIONS--The outcome of delivery was not influenced by parity. Both antenatal and intrapartum care were responsible for the higher perinatal mortality rate in the isolated general practitioner units. The integrated unit, which shared midwifery staff with the consultant unit, seemed to work well. Analysis by intended place of delivery at the time of onset of labour or diagnosis of intrauterine death suggested that the care given in isolated units needs to be improved, perhaps by better training of general practitioners and consultant supervision of antenatal care.     

Maternal and Perinatal Mortality Associated with Cesarean Section in Alberta (1955-1959)

A province-wide study of perinatal mortality was initiated in Alberta (population 1,283,000) in 1955. The period 1955-1959 covered 182,028 total births and 4219 perinatal deaths of which 260 were from 3813 Cesarean sections.The perinatal mortality rate in Cesarean-section births in rural hospitals (101.4 per thousand Cesarean births) was compared with that for urban hospitals (55.7 per thousand).Examination of the indications for primary Cesarean section in which a perinatal death occurred showed that hemorrhage accounted for 54 out of 85 of these deaths in rural hospitals, and 49 out of 110 similar urban deaths. Of 33 perinatal deaths associated with elective repeat sections, 17 were of premature babies.Eleven of the 85 maternal deaths during 1955-1959 were associated with Cesarean section, a maternal mortality rate of 28.8 per 10,000 Cesarean section births. Preventable factors were present in 8 of the 11 cases. Hemorrhage was the primary cause of death.     

Evaluating perinatal mortality rates: effects of referral and case mix.

OBJECTIVE--To evaluate perinatal mortality rates as a method of auditing obstetric and neonatal care after account had been taken of transfer between hospitals during pregnancy and case mix. DESIGN--Case-control study of perinatal deaths. SETTING--Leicestershire health district. SUBJECTS--1179 singleton perinatal deaths and their selected live born controls among 114,362 singleton births to women whose place of residence was Leicestershire during 1978-87. MAIN OUTCOME MEASURE--Crude perinatal mortality rates and rates adjusted for case mix. RESULTS--An estimated 11,701 of the 28,750 women booked for delivery in general practitioner maternity units were transferred to consultant units during their pregnancy. These 11,701 women had a high perinatal mortality rate (16.8/1000 deliveries). Perinatal mortality rates by place of booking showed little difference between general practitioner units (8.8/1000) and consultant units (9.3-11.7/1000). Perinatal mortality rates by place of delivery, however, showed substantial differences between general practitioner units (3.3/1000) and consultant units (9.4-12.6/1000) because of the selective referral of high risk women from general practitioner units to consultant units. Adjustment for risk factors made little difference to the rates except when the subset of deaths due to immaturity was adjusted for birth weight. CONCLUSION--Perinatal mortality rates should be adjusted for case mix and referral patterns to get a meaningful result. Even when this is done it is difficult to compare the effectiveness of hospital units with perinatal mortality rates because of the increasingly small subset of perinatal deaths that are amenable to medical intervention.     

Eight-year study of social and ecological correlates of mortality among immature baboons of Mikumi National Park,Tanzania

The Cox Proportional Hazards Regression Model was used to examine ecological and sociodemographic correlates of mortality among 164 immature yellow baboons born over an 8-year period at Mikumi National Park, Tanzania. Ecological correlates were derived from seasonal rainfall. Mortality was lowest for immatures born during the late rainy season, when it was likely that nourishment for pregnant and lactating females was greatest. High mortality was associated with above-average rainfall early in the immature's first complete rainy season. This association may result from one or more of the following: exposure, increased ranging, or accelerated vegetation growth, each of which is thought to increase hazards for weanlings. When births for the 8 years of the study were pooled, a birth peak occurred during the early dry season. The larger number of births during a birth peak should intensify competition among mothers and among immatures. Mortality was greatest for immature females born during the season immediately following the birth peak, while lowest for immature females born during the season immediately preceding the peak. Immature female mortality was greatest when the troop size at birth was large, and was most severe for females born to low ranking mothers. The sociodemographic results are consistent with Wasser's hypothesis that cooperative attacks of female baboons upon other troop females suppress the others' reproduction and the vitality of their infants, thereby improving the relative competitive position of the attackers' own young.     

The effect of divorce on infant mortality in a remote area of Bangladesh

The process of divorce is usually lengthy and hazardous, and can start quarrels that can lead to the abuse of women and their children. This study examines the effects of divorce on neonatal and postneonatal mortality of babies born before and after divorce in Teknaf, a remote area of Bangladesh. The longitudinal demographic surveillance system (DSS) followed 1,762 Muslim marriages in 1982-83 for 5 years to record divorce, deaths of spouse, emigration and births. It recorded 2,696 live births during the follow-up period, and their survival status during infancy. Logistic regression models were used to estimate the effect of divorce on neonatal and postneonatal mortality, controlling for maternal age at birth, parity, sex of the child and household economic status. The odds of neonatal and postneonatal deaths among babies born after divorce or less than 12 months before mothers were divorced were more than double the odds of those born to mothers of intact marriages. The odds of postneonatal deaths were two times higher among babies born more than 12 months before divorce happens than their peers. The high mortality of infants born before and after mothers were divorced may reflect how abusive marriage and divorce increase the vulnerability of women and children in rural Bangladesh. Divorce and abuse of women are difficult and intractable social and health problems that must be addressed.     

Long-term data on the reproduction and maintenance of a colony of common marmosets (Callithrix jacchus jacchus) 1972-1983

We have used our laboratory records to compare data on the reproduction and maintenance of common marmosets in different colonies and to provide additional information on the species in captivity. Data are presented for a period of 12 years. This was long enough to allow information on longevity, mortality, aggression and incest. In addition 543 infants were born from a total of 202 births. No seasonality was found and the highest proportion of births overall was that of triplets. A significantly greater proportion of males was born, but perinatal mortality reduced this to a proportion of 52.2% surviving males. The interbirth interval for all normal births ranged from 145 to 382 days, with a median of 158 days. There was no evidence that interbirth intervals increased with age. The proportion of non-breeding pairs was small (4 out of 28) and progesterone assays showed that these females were ovulating.     

The Scottish perinatal mortality survey.

Perinatal deaths in single births that occurred in Scotland during 1977 were investigated by case-record analysis. Causes of death were divided into nine categories, an extended version of the Aberdeen classification being used. Out of 1012 single perinatal deaths, 265 were due to fetal abnormality, which in 140 cases was malformation of the central nervous system. Of the 747 normally formed infants, 446 weighed 1500 g or more, of whom 82 died intra partum and 154 were born alive. The largest single cause of death was low birth weight in normally formed babies whose mothers had no complications of pregnancy (302 cases). Of these babies, 103 (34%) were growth-retarded. Rhesus incompatibility (16 deaths) and maternal diabetes (seven deaths) were not major causes of perinatal loss. These results were thought to be valuable in illustrating the main causes of perinatal mortality and directing attention to important issues. Hence a modified version of the study is being continued to see whether yearly audit by regional assessors is a feasible and practical way of monitoring trends in perinatal mortality.     

Birth order,gestational age,and risk of delivery related perinatal death in twins: retrospective cohort study

ObjectiveTo determine whether twins born second are at increased risk of perinatal death because of complications during labour and delivery.DesignRetrospective cohort study.SettingScotland, 1992 and 1997.ParticipantsAll twin births at or after 24 weeks'' gestation, excluding twin pairs in which either twin died before labour or delivery or died during or after labour and delivery because of congenital abnormality, non-immune hydrops, or twin to twin transfusion syndrome.ResultsOverall, delivery related perinatal deaths were recorded for 23 first twins only and 23 second twins only of 1438 twin pairs born before 36 weeks (preterm) by means other than planned caesarean section (P>0.99). No deaths of first twins and nine deaths of second twins (P=0.004) were recorded among the 2436 twin pairs born at or after 36 weeks (term). Discordance between first and second twins differed significantly in preterm and term births (P=0.007). Seven of nine deaths of second twins at term were due to anoxia during the birth (2.9 (95% confidence interval 1.2 to 5.9) per 1000); five of these deaths were associated with mechanical problems with the second delivery following vaginal delivery of the first twin. No deaths were recorded among 454 second twins delivered at term by planned caesarean section.ConclusionsSecond twins born at term are at higher risk than first twins of death due to complications of delivery. Previous studies may not have shown an increased risk because of inadequate categorisation of deaths, lack of statistical power, inappropriate analyses, and pooling of data about preterm births and term births.

What is already known on this topic

It is difficult to assess the wellbeing of second twins during labourDeliveries of second twins are at increased risk of mechanical problems, such as cord prolapse and malpresentation, after vaginal delivery of first twinsIncreased risks of perinatal death in second twins have not been shown, but the methods of these studies were flawed

What this study adds

Second twins delivered at term are at increased risk of delivery related perinatal deathsIntrapartum anoxia caused 75% of these deaths in second twins, and most of these resulted from mechanical problems after vaginal delivery of first twinsPlanned caesarean section of twins at term may prevent perinatal deaths     

Outcomes of Regionalized Perinatal Care in Washington State

We evaluated the extent to which the regionalization of perinatal care in Washington State has succeeded in concentrating high-risk pregnancies in technologically appropriate referral centers and in reducing differences in neonatal outcome among hospitals. Of all infants weighing less than 1,500 grams born between 1980 and 1983, nearly 68% were delivered in level III hospitals, although only 24% of all babies are born in these hospitals, indicating that the state is highly regionalized. Neonatal outcomes—as measured by standardized mortality ratios—are similar in level I, II and III hospitals and are not greatly influenced by the rural or urban location of the hospital. The most promising strategy for further reducing neonatal mortality is to decrease the number and proportion of very-low-birth-weight births.     

A note on the fetal-infant mortality problem

This paper considers the age pattern of mortality between conception and first birthday. It highlights the various problems that still limit our understanding of the ways in which the age components of mortality are associated, especially during the perinatal period. A mathematical function is fitted which captures the interaction between six mortality components for a typical high mortality society, one in which the infant mortality rate is 150 per thousand live births. This experiment helps to clarify the need to link infant with fetal mortality, to conduct further research on the level of risk in each component, and to consider the cumulative early-age mortality profile in its entirety.     

Congenital and hereditary anomalies in the rhesus monkeys (Macaca mulatta) of Cayo Santiago

During seven annual birth seasons, from January 1976 to July 1982, 963 infants were born in the Cayo Santiago, Puerto Rico, colony of free-ranging rhesus monkeys (Macaca mulatta). The reproductive rate for mature females, 4 years of age and older, ranged between 74.1% and 84.7%, with a cumulative mean of 80.8% over 7 years. Live births comprised 95.3% of the total and the secondary sex ratio was 109 male to 100 female births. No twinning was observed. Aborted and stillborn monkeys represented 4.7% of all births. The percentage of stillborn females was greater than that of males (4.0% vs. 3.1%). Neonatal death, defined as mortality within 48 hours postpartum, occurred in 0.8% of the live births. Two cases of congenital abnormalities were observed. The first was an anencephalic, acranial female and the second a congenitally blind male. Both infants were born to matrilineally unrelated 7-and 8-year-old multiparous females with no prior history of delivering malformed offspring. The incidence of each defect, based on 963 births, was 0.10%, with a cumulative incidence of 0.20% for all teratisms seen during the study. Multiple occurrences of a rare, nonpathological and nonlethal hereditary anomaly were also seen. Five "golden" macaques were born into two genetically distinct social groups within the last 2 years of observation. The incidence of this phenotype, based on five cases, was 0.52%, 52 times the expected rate (.01%).     

Maternal reproductive experience enhances early postnatal outcome following gestation and birth of rats in hypergravity

A major goal of space life sciences research is to broaden scientific knowledge of the influence of gravity on living systems. Recent spaceflight and centrifugation studies demonstrate that reproduction and ontogenesis in mammals are amenable to study under gravitational conditions that deviate considerably from those typically experienced on Earth (1 x g). In the present study, we tested the hypothesis that maternal reproductive experience determines neonatal outcome following gestation and birth under increased (hyper) gravity. Primigravid and bigravid female rats and their offspring were exposed to 1.5 x g centrifugation from Gestational Day 11 either through birth or through the first postnatal week. On the day of birth, litter sizes were identical across gravity and parity conditions, although significantly fewer live neonates were observed among hypergravity-reared litters born to primigravid dams than among those born to bigravid dams (82% and 94%, respectively; 1.0 x g controls, 99%). Within the hypergravity groups, neonatal mortality was comparable across parity conditions from Postnatal Day 1 through Day 7, at which time litter sizes stabilized. Maternal reproductive experience ameliorated neonatal losses during the first 24 h after birth but not on subsequent days, and neonatal mortality was associated with changes in maternal care patterns. These results indicate that repeated maternal reproductive experience affords protection against neonatal losses during exposure to increased gravity. Differential mortality of neonates born to primigravid versus bigravid dams denotes gravitational load as one environmental mechanism enabling the expression of parity-related variations in birth outcome.     

Perinatal mortality: a continuing collaborative regional survey.

A collaborative survey of perinatal mortality in each district of the Northern region set up in July 1980 was able to obtain information on 99% of all the registered perinatal deaths among babies born in 1981-2 to mothers resident in the region. There were 12.4 perinatal deaths/1000 births over this two year period, but 41% of the stillbirths and early neonatal deaths were of babies with a lethal malformation or weighing less than 1000 g at birth (or both). All causes of perinatal mortality had become less common than they had been at the time of the National Birthday Trust survey in 1958, though there had been a relatively small decrease in the number of deaths due to malformation (in the absence of any neural tube defect) and in the number of stillbirths of normally developed fetuses: 36% of the antepartum stillbirths among non-malformed singleton fetuses were associated with poor fetal growth (weight below the fifth centile at birth) and 21% were due to sudden unexplained placental abruption.