Asian mothers' risk factors for perinatal death--the same or different? A 10 year review of Leicestershire perinatal deaths.

A case-control study of all perinatal deaths in Leicestershire was established in 1976. By 1985 some 1342 singleton perinatal deaths had occurred. Perinatal mortality among patients of Asian origin was consistently higher than that among European women. Many of the sociomedical risk factors for perinatal death known at booking were common to both population groups. In this population of Asian women, however, low social class was not associated with perinatal risk and illegitimacy hardly ever occurred. In contrast, previous infertility among the Asian women was associated with risk of perinatal death, while no such association was found with European women. In 19% of perinatal deaths care was either inadequately provided or taken up. The case-control design in these circumstances provides a practicable way to evaluate causal factors and at the same time to provide information of value to educators and health service planners.     

Quality of obstetric care provided for Asian immigrants in Leicestershire.

Between 1976 and 1981 some 939 perinatal deaths occurred to women living in Leicestershire, of which 128 (14%) were to Asian women. The qualifications of the general practitioners, the gestation at which women start antenatal care, and perinatal death were used as structural, process, and outcome measures for evaluating the services provided to Asian immigrants within this population. Perinatal deaths were divided into four groups: congenital malformation, macerated stillbirth, asphyxia in labour, and immaturity. Asian mothers had one and a half times the risk of perinatal mortality when social class, parity, height, legitimacy, and the general practitioner''s qualifications were taken into account. Asian and non-Asian mothers with general practitioners who were not on the obstetric list had more than twice the risk of a perinatal death when a similar adjustment was made. Recommendations include priority allocation of community midwives to practitioners not on the obstetric list, the establishment of postgraduate courses for such doctors, and the continued evaluation of the effect of such proposals on perinatal mortality.     

Prevalence of, and risk factors associated with, perinatal calf mortality in pasture-based Holstein-Friesian cows

Recent publications indicate that the prevalence of perinatal mortality has increased in some dairy industries and an increased proportion of this loss is not associated with the traditional risk factors for perinatal mortality. The objectives of this study were to establish the prevalence of perinatal mortality (calf death within 24 h of calving) in Irish dairy herds and to determine the current significance of putative risk factors in pasture-based management systems. A total of 182 026 records of full-term calvings from Holstein-Friesian dams served by artificial insemination (AI) sires of seven breeds in herds of 20 calvings or more per year were available from the Irish national breeding database over 4 years (2002 to 2005). The prevalence of perinatal mortality was 4.29% (7.7% in primiparae and 3.5% in pluriparae). The likelihood of perinatal mortality increased between 2002 and 2005 and was greatest in June and in winter. There was an interaction (P < 0.001) between the effect of calving assistance and parity with the effect of dystocia on perinatal mortality being greater in primiparae. The odds of perinatal mortality were greater in male (OR = 1.12; P < 0.001) and in twin calves (OR = 5.70-13.36; P < 0.001) and in dams that had perinatal mortality at the previous calving (OR = 4.21; P < 0.001). The logit of the probability of perinatal mortality increased by 0.099 per unit increase in sire predicted transmitting ability (PTA) for direct perinatal mortality. The probability of perinatal mortality increased at an increasing rate in primiparae as animals calved at a younger age relative to the median age at first calving. The only herd-level factor examined, herd size did not affect the odds of perinatal mortality. These data indicate that the prevalence of perinatal mortality in this cattle population is similar to that in other pasture-based dairy systems worldwide. The putative exposures and attributes traditionally associated with perinatal mortality were associated with perinatal mortality in this pasture-based dairy cow population. The practical implication of these results is that as many of the significant risk factors are largely not under management control (year of calving, month of calving, twin calving, primiparity, previous perinatal mortality and foetal gender), herd owners must focus on the significant determinants under their control (age at first calving, sire genetic merit for direct perinatal mortality and both the extent of calving supervision and the degree of assistance), in order to reduce the prevalence of perinatal mortality and improve perinatal welfare.     

重症医学病房中早产儿死亡危险因素的单变量logistic 回归 分析研究

目的:探讨重症医学病房内早产儿的相关性危险因素对其死亡的影响.方法:回顾性收集我重症医学病房从2008年6月1日至2011年8月31日收治的早产患儿共45例,分组后,对相关死亡危险因素进行logistics回归分析研究.结果:45例早产儿死亡的相关危险因素为出生体重(OR=4.157),体重越低,死亡率越高.结论:加强孕期保健,优化围产期管理,促进胎儿成熟,加强对低出生体重儿的管理,可提高早产儿的存活率和存活质量.     

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     

Third trimester placental grading by ultrasonography as a test of fetal wellbeing.

In a study of 2000 unselected pregnant women the development of a mature placental appearance (grade 3) on ultrasonography by 34-36 weeks'' gestation, observed in 15% of cases, was associated with maternal smoking, low parity, low maternal age, and being white. These women had an increased risk of problems during labour and their babies had an increased risk of low birth weight, poor condition at birth, and perinatal death. The women were randomly allocated to two groups: in one group the result of the placental grading was reported to the clinician responsible for care; in the second the result was noted but not reported. There was a significant decrease in the risk of perinatal death in the group where the grading was known. This reduction was responsible for a difference in the principal outcome index, a heterogeneous group of measures of mortality and morbidity, but this difference was not significant. This study alone does not justify routine late scanning, and further, larger trials are required. Nevertheless, the results do provide a basis for the reporting of placental grading when ultrasound examination is performed during the third trimester.     

Perinatal mortality in eastern Uganda: a community based prospective cohort study

Background

To achieve a child mortality reduction according to millennium development goal 4, it is necessary to considerably reduce neonatal mortality. We report stillbirth and early neonatal mortality risks as well as determinants of perinatal mortality in Eastern Uganda.

Methods

A community-based prospective cohort study was conducted between 2006 and 2008. A total of 835 pregnant women were followed up for pregnancy outcome and survival of their children until 7 days after delivery. Mother''s residence, age, parity, bed net use and whether delivery took place at home were included in multivariable regression analyses to identify risk factors for perinatal death.

Results

The stillbirth risk was 19 per 1,000 pregnancies and the early neonatal death risk 22 per 1,000 live births. Overall, the perinatal mortality risk was 41 [95%CI: 27, 54] per 1,000 pregnancies. Of the deaths, 47% followed complicated deliveries and 24% preterm births. Perinatal mortality was 63/1,000 pregnancies among teenage mothers, 76/1,000 pregnancies among nulliparous women and 61/1,000 pregnancies among women delivering at home who, after controlling for potential confounders, had a 3.7 (95%CI: 1.8, 7.4) times higher perinatal mortality than women who gave birth in a health facility. This association was considerably stronger among nulliparous women [RR 8.0 (95%CI: 2.9, 21.6)] than among women with a previous live birth [RR 1.8 (95%CI: 0.7, 4.5)]. All perinatal deaths occurred among women who did not sleep under a mosquito net. Women living in urban slums had a higher risk of losing their babies than those in rural areas [RR: 2.7 (95%CI: 1.4, 5.3)].

Conclusion

Our findings strengthen arguments for ensuring that pregnant women have access to and use adequate delivery facilities and bed nets.     

Perinatal outcome of pregnancies in women aged 40 and over

Perinatal outcome of pregnancies at forty and over was analyzed starting from the diagnosis of pregnancy to seven days following delivery. Retrospectively, pre-gestational health and reproduction status were dealt with, as well as the course of pregnancy, deliveries, and newborn children (study group). The control group was composed of pregnant women aged 20 to 29, who were identical to study group in terms of parity. Statistical data processing was done by means of chi2-test, and contingency 2 x 2 tables. The difference was significant if p < 0.05. Out of 2,099 diagnosed wanted pregnancies at forty and over, 415 (19.8%) had a miscarriage, in 33 (1.6%) an artificial abortion was performed after determining the fetus karyotype and 1,651 (78.2%) of pregnant women delivered. In 66.2% of pregnancies the fetus karyotype was determined and in 33 (2.5%) fetuses chromosomal abnormalities were found Incidence of deliveries at 40 and over is 1.38%, which is a 35.6-percent increase in the last ten years. Nullipara and pluripara had an increase, and multipara had a decrease. Pre-gestational health and reproduction status in study group is lower than in control group. Complications during pregnancy: threatened abortion, EPH gestosis, placenta praevia, gestational diabetes, late fetal death are more frequent than in control group (p < 0.05). In intrapartal terms, more frequent were induction of delivery, meconium-stained amniotic fluid, fetal distress, operative vaginal deliveries, and Cesarean section (p < 0.05). In neonatal outcome there are more premature infant, there are more VLBW, LBW, SGA, newborn with low Apgar index values, and the total perinatal death is greater than in the control group (p < 0.05). In perinatal terms, (from the diagnosis to the seventh day following delivery) 1,617 children survived (77.0%), meaning that perinatal loss was 482 (23.0%). Authors conclude that pregnancy at 40 and over is a high-risk pregnancy. There is a high risk of pre-gestational and gestational complications, and perinatal loss is high. Therefore, those pregnancies are not desirable from the medical point of view.     

Cigarettes pendant la grossesse,poids de naissance et mortalité périnatale

This study is based on a 10% random sample of medical certifications of birth in Quebec in 1970-71 and on additional information obtained from perinatal death certificates and birth registrations. Smoking in pregnancy significantly reduced the average birth weight after 35 weeks of gestation. It increased the risk of perinatal death by 24%. This increase was concentrated in the age groups under 25 and 35 +, in the parity groups 0 and 4 + and among women with less than 12 years of schooling. The proportion of mothers smoking during pregnancy was 43.2% and ranged as high as 62.2% among those under 20 with less than eight years of schooling. These depressingly high percentages imply that new educational approaches aimed particularly at high-risk groups should be developed and evaluated.     

Methods and models to determine perinatal status of Florida manatee carcasses

Differences in perinatal mortality can be indicators of differences in physiology, behavior, toxicology, population dynamics, and ecology of species and individuals. Extensive data collected under the Florida Manatee Carcass Recovery Program provide important information about manatee perinatal mortality. However, early age at death can be difficult to determine for often highly decomposed carcasses. Here, I provide quantitative methods to identify perinatal status for manatee carcasses. First, perinatal and nonperinatal mortality were defined based on physiological indicators. After review of necropsy reports, specific length classes became clear indicators of perinatal status: carcasses <82‐cm long were always perinatal, and carcasses >160‐cm long were always nonperinatal. Using data from carcasses 82–160 cm long of known perinatal status, Bayesian models quantify the relationship among age at death, carcass length, and carcass recovery month. The models predict the perinatal status of carcass 82–160 cm long when physiological indicators are unavailable. Overall, perinatal status could be determined for 98.2% of carcasses collected from 1978 to 2005. Initial examination of the fraction of perinatal mortalities within the entire carcass sample reveals interesting spatial and temporal patterns that warrant further analyses.     

Influence of maternal age, parity and social class on perinatal mortality in Scotland: 1960-82

This study examines secular changes in the influence of maternal age, parity and social class on perinatal mortality in Scotland. Using cross-sectional national data on all Scottish legitimate births the effects of these factors are estimated on the risk of stillbirths, neonatal and perinatal deaths, and the extent to which the current pattern of relative risks in the early 1980s has changed over the past 2 decades is investigated. Social class is used as a crude measure of relative as opposed to absolute differences in socioeconomic conditions which may influence reproductive outcomes. The effects of age, parity and social class are estimated using logistic models. The most parsimonious model adequately describing the data is provided by a main effects model without interactions. Despite changes in reproductive behavior, improved access to maternity services and more effective perinatal care, the influence of maternal age and social class on perinatal mortality remained unchanged between 1960 and 1982. Although the absolute risks of stillbirths and neonatal deaths declined in all maternal age groups, this improvement was not accompained by a significant change in the relative risks traditionally associated with age. Despite no significant changes in the traditional J-shaped association between parity and stillbirths, cross-sectional analysis shows that in the early 1980s the risk of both neonatal and perinatal deaths decreased as parity increased. This finding is consistent with the pattern of risks observed in longitudinal studies and retrospective surveys of reproductive histories. In view of the stability of age, parity and social class effects on the risk of perinatal mortality, little if any of the overall decrease in Scottish stillbirth and neonatal death rates can be attributed to a significant narrowing of relative risks. The results suggest that the attributable risk of high maternal age or low social class on perinatal mortality is negligible. Future improvements in perinatal mortality are thus likely to result from a continuation of the uniform decrease in perinatal mortality for women of all ages, parities and social classes and not from a diminishing of differences in relative risks which are now virtually identical for a large and growing % of women in Scotland.     

Is Gestational Hypertension Protective against Perinatal Mortality in Twin Pregnancies?

Background

Pregnancy-induced or gestational hypertension is a common pregnancy complication. Paradoxically, gestational hypertension has been associated with a protective effect against perinatal mortality in twin pregnancies in analytic models (logistic regression) without accounting for survival time. Whether this effect is real remains uncertain. This study aimed to validate the impact of gestational hypertension on perinatal mortality in twin pregnancies using a survival analysis approach.

Methods

This was a retrospective cohort study of 278,821 twin pregnancies, using the U.S. 1995–2000 matched multiple birth dataset (the largest dataset available for multiple births). Cox proportional hazard models were applied to estimate the adjusted hazard ratios (aHR) of perinatal death (stillbirth and neonatal death) comparing gestational hypertensive vs. non-hypertensive pregnancies controlling for maternal characteristics and twin cluster-level dependence.

Results

Comparing births in gestational hypertensive vs. non-hypertensive twin pregnancies, perinatal mortality rates were significantly lower (1.20% vs. 3.38%), so were neonatal mortality (0.72% vs. 2.30%) and stillbirth (0.48% vs. 1.10%) rates. The aHRs (95% confidence intervals) were 0.34 (0.31–0.38) for perinatal death, 0.31 (0.27–0.34) for neonatal death, and 0.45 (0.38–0.53) for stillbirth, respectively. The protective effect of gestational hypertension against perinatal death became weaker over advancing gestational age; the aHRs in very preterm (<32 weeks), mild preterm (32–36 weeks) and term (37+ weeks) births were 0.29, 0.48 and 0.76, respectively. The largest risk reductions in neonatal mortality were observed for infections and immaturity-related conditions.

Conclusions

Gestational hypertension appears to be beneficial for fetal survival in twin pregnancies, especially in those ending more prematurely or for deaths due to infections and immaturity-related conditions. Prospective studies are required to rule out the possibility of unmeasured confounders.     

Canine perinatal mortality: a cohort study of 224 breeds

Canine perinatal mortality is known to be relatively high. However, the literature on perinatal mortality in dogs is still sparse and often refers to a single or only a few breeds. The aim of this large-scale observational study was to describe the perinatal mortality in purebred dogs of various breeds at both puppy and litter level. In addition, the influence of breed, breed size, litter size, age of the bitch, litter number and season for whelping on the risk of perinatal mortality at litter level was studied and the mean litter size at eight days and eight wks after birth was calculated. A retrospective cohort study was performed by studying 10,810 litters of 224 breeds registered in the Norwegian Kennel Club in 2006 and 2007. Perinatal mortality was defined as the sum of stillborn puppies and puppies that died during the first wk after birth (early neonatal mortality) and was present in 24.6% of the litters. Eight percent of the puppies died before eight days after birth, with 4.3% as stillbirth and 3.7% as early neonatal mortality. For most breeds the perinatal mortality was low, but for some breeds a higher perinatal mortality was found. The mean litter size at eight days and eight wks after birth was 4.97 (±0.02) and 4.92 (±0.02) puppies, respectively. Of all puppies born, only 1% died during the period from eight days to eight wks after birth. Random effects logistic regression analysis indicated that increasing litter size and age of the bitch were associated with an increased risk of stillbirth, early neonatal mortality and total perinatal mortality at the litter level (P < 0.001). The random breed effect was significant for all outcomes. Litter number also had a significant effect on stillbirth, early neonatal mortality and total perinatal mortality at the litter level, with the highest risk of perinatal mortality found in the first litter (P < 0.001). Further, the risk of early neonatal mortality was doubled in litters with stillborn puppies. No significant effect of whelping season on perinatal mortality at litter level was found. An interaction existed between the age of the bitch and litter number and the risk of stillbirth was three times as high (odds ratio = 3.00) in litters from bitches having their first litter after the age of six y. Breed was a more important determinant of perinatal mortality in litters than breed size. However, more than 90% of the variation in perinatal mortality was found at the individual litter level and efforts to minimize puppy mortality should be targeted at the management of the individual litter rather than at the breed level.     

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.     

Support after perinatal death: a study of support and counselling after perinatal bereavement.

After an earlier study into the practical aspects of the management of perinatal death, a counselling service was introduced for parents whose baby had died in the perinatal period. The service was monitored, and the parents who received the service were compared with a group that did not. Fifty families were allocated randomly either to the counselling (supported) group or to the contrast group, who received routine hospital care. Assessment was carried out at six and 14 months after the death, using a semi-structured interview and two self-rating scales (the general health questionnaire and the Leeds scales). Two of 16 mothers in the supported group showed psychiatric disorder at six months, compared with 10 of 19 in the contrast group (p less than 0.01, Fisher''s exact test). There was no significant difference between the two groups at 14 months, when 80% of all the women studied had recovered psychiatric symptoms. Socially isolated women and those who marital relations lacked intimacy had a higher incidence of psychiatric symptoms at six months. Early pregnancy (within six months) was associated with a higher incidence of psychiatric symptoms in the unsupported group. The duration of bereavement reaction after perinatal death was appreciably shortened by support and counselling.     

Maternal smoking in pregnancy and sex differences in perinatal death between boys and girls

The sex difference in perinatal mortality in developed countries is largely unexplained. The current study evaluated the differences in the impact of maternal smoking during pregnancy on the risk of perinatal death between males and females. The analysis involved 11,469 and 9,404 newborns derived from two population-based birth cohorts in Northern Finland, for 1966 and 1985-86, respectively. The perinatal mortality rate was 23 per thousand in the 1966 cohort and 9 per thousand in the 1985-86 cohort. The rate ratio (RR) for mortality for males over females is 1.15 and 1.60 in the two cohorts, respectively. Among children whose mothers smoked during pregnancy, the RR was 2.2 (95% CI 1.0, 4.7) for the former cohort and 4.8 (95% CI 1.5, 15.2) for the later cohort; and among the children whose mothers did not smoke the corresponding RR was 1.2 (95% CI 0.9, 1.6) and 1.1 (95% CI 0.6, 1.9). Maternal smoking during pregnancy could be an important determinant accounting for the excess perinatal death for males over females. Our results encourage evaluation of the findings among other populations.     

Obstetric practice and outcome of pregnancy in Cardiff residents 1965-73.

Trends in management and outcome of pregnancy in Cardiff residents from 1965 to 1973 were reviewed. The mean age and parity of parturients fell. Hospital delivery became almost universal, monitoring the fetus during pregnancy was introduced, and induction and acceleration of labour became commonplace. These developments were not associated with any striking change in either the total perinatal death rate or the timing or cause of perinatal death. Possibly a real change in perinatal mortality between 1965 and 1973 was masked by random fluctuation of small numbers, or possibly factors peculiar to the Cardiff population prevented a decrease in perinatal mortality that would otherwise have resulted from improved medical care. Only by large-scale randomised trials can the true value of induction and other medical developments be assessed.     

妊娠期肝内胆汁淤积症256例临床分析

目的：探讨改善妊娠期肝内胆汁淤积症患者围生结局及围生儿预后的方法。方法：对2006年3月．2011年3月在我院住院分娩的256例ICP患者及从我院住院无并发症正常分娩的10112个患者中随机抽取的256例患者的产检情况、分娩方式、围生儿结局进行回顾性分析。结果：ICP组与对照组在分娩方式、产后出血、早产、新生儿窒息、羊水粪染、圉产儿死亡等方面比较差异均具有统计学意义（P〈0．05）;产检组与未检组在产后出血、早产、新生儿窒息、羊水粪染、围产儿死亡等方面比较差异有统计学意义（P〈0．05）。结论：妊娠期肝内胆汁淤积症可增加早产、胎儿宫内窘迫、新生儿窒息、产后出血发生率,重视产前检查和孕期保健,对ICP患者做到早发现、早诊断、早治疗,选择适当分娩方式、适时终止妊娠,对改善围生结局及围生儿预后有积极的意义。     

Maternal and Perinatal Outcomes of Twin Pregnancy in 23 Low- and Middle-Income Countries

Background

Twin pregnancies in low- and middle-income countries (LMICs) pose a high risk to mothers and newborns due to inherent biological risks and scarcity of health resources. We conducted a secondary analysis of the WHO Global Survey dataset to analyze maternal and perinatal outcomes in twin pregnancies and factors associated with perinatal morbidity and mortality in twins.

Methods

We examined maternal and neonatal characteristics in twin deliveries in 23 LMICs and conducted multi-level logistic regression to determine the association between twins and adverse maternal and perinatal outcomes.

Results

279,425 mothers gave birth to 276,187 (98.8%) singletons and 6,476 (1.2%) twins. Odds of severe adverse maternal outcomes (death, blood transfusion, ICU admission or hysterectomy) (AOR 1.85, 95% CI 1.60–2.14) and perinatal mortality (AOR 2.46, 95% CI 1.40–4.35) in twin pregnancies were higher, however early neonatal death (AOR 2.50, 95% CI 0.95–6.62) and stillbirth (AOR 1.22, 95% CI 0.58–2.57) did not reach significance. Amongst twins alone, maternal age <18, poor education and antenatal care, nulliparity, vaginal bleeding, non-cephalic presentations, birth weight discordance >15%, born second, preterm birth and low birthweight were associated with perinatal mortality. Marriage and caesarean section were protective.

Conclusions

Twin pregnancy is a significant risk factor for maternal and perinatal morbidity and mortality in low-resource settings; maternal risk and access to safe caesarean section may determine safest mode of delivery in LMICs. Improving obstetric care in twin pregnancies, particularly timely access to safe caesarean section, is required to reduce risk to mother and baby.