Clinical and pathologic correlates of stillbirths in a single institution

Disorders of placental villous maturation in fetal death

Objective The aims of this study were to ascertain the frequency of disorders of villous maturation in fetal death and to also delineate other placental histopathologic lesions in fetal death. Methods This was a retrospective observational cohort study of fetal deaths occurring among women between January 2004 and January 2016 at Hutzel Women's Hospital, Detroit, MI, USA. Cases comprised fetuses with death beyond 20 weeks' gestation. Fetal deaths with congenital anomalies and multiple gestations were excluded. Controls included pregnant women without medical/obstetrical complications and delivered singleton, term (37-42 weeks) neonate with 5-min Apgar score ≥7 and birthweight between the 10th and 90th percentiles. Results Ninety-two percent (132/143) of placentas with fetal death showed placental histologic lesions. Fetal deaths were associated with (1) higher frequency of disorders of villous maturation [44.0% (64/143) vs. 1.0% (4/405), P < 0.0001, prevalence ratio, 44.6; delayed villous maturation, 22% (31/143); accelerated villous maturation, 20% (28/143); and maturation arrest, 4% (5/143)]; (2) higher frequency of maternal vascular malperfusion lesions [75.5% (108/143) vs. 35.7% (337/944), P < 0.0001, prevalence ratio, 2.1] and fetal vascular malperfusion lesions [88.1% (126/143) vs. 19.7% (186/944), P < 0.0001, prevalence ratio, 4.5]; (3) higher frequency of placental histologic patterns suggestive of hypoxia [59.0% (85/143) vs. 9.3% (82/942), P < 0.0001, prevalence ratio, 6.8]; and (4) higher frequency of chronic inflammatory lesions [53.1% (76/143) vs. 29.9% (282/944), P < 0.001, prevalence ratio 1.8]. Conclusion This study demonstrates that placentas of women with fetal death were 44 times more likely to present disorders of villous maturation compared to placentas of those with normal pregnancy. This suggests that the burden of placental disorders of villous maturation lesions is substantial.

Placental Findings in Singleton Stillbirths: A Case-control Study

AIMS

This prospective observational study compared placental lesions of stillbirth cases and live birth controls, and aimed to determine the cause of stillbirth.

METHODS

The study enrolled 85 stillbirths and 85 live births at the time of delivery.

RESULTS

There was significantly increased incidence of placental abruption (p = 0.005) and gestational diabetes (p = 0.032) in mothers with stillbirths. Histopathological examination of placenta was significantly abnormal in stillbirths compared with live births (p = 0.004). Delayed villous maturation was significantly more in stillbirths (38.82 vs. 16.47%; p = 0.002). Acute (30.59 vs. 16.47%; p = 0.04) and chronic diffuse villitis (16.47 vs. 4.7%; p = 0.02), chorionic plate acute vasculitis (28.235 vs. 14.11%; p = 0.04) were significantly more in stillbirths. Foetal vascular thrombi in the chorionic plate (30.58 vs. 14.12%; p = 0.02) and avascular villi (24.7 vs. 8.23%; p = 0.006) were significantly more in stillbirths.

CONCLUSION

These abnormal placental patterns could provide information about the etiopathogenisis in stillbirths of unknown aetiology.

Diagnostic value of perinatal autopsies: analysis of 486 cases

AIM

Autopsy is a beneficial procedure to determine the cause of death and the frequency of anomalies in perinatal losses. Even in the event of an autopsy not providing any additional information, completion of the procedure confirming the clinical diagnoses gives reassurance to both clinicians and parents. Here we present a 15-year archival study based on findings of perinatal autopsies.

DESIGN AND METHODS

Four hundred and eighty-six cases from our archive were reviewed and according to the findings they were divided into three subcategories; (1) miscarriages (MCF); (2) fetuses terminated (FTA) for vital anomalies detected by prenatal ultrasonography; (3) premature or term newborns died within first month of life (neonates: NN). Autopsies were documented and classified according to week/age of cases, anomalies and causes of abortion or death.

RESULTS

Two hundred and twenty-six of 486 cases (46.5%) were in MCF group while 227 (46.7%) and 33 (6.8%) were of them in FTA and NN groups, respectively. In FTA group, the most frequent anomaly detected was neural tube defects. In NN group, prematurity related complications were the most common cause of death. The autopsy process was found valuable in 39.7% of all cases.

CONCLUSIONS

We suggest that autopsy procedure is diagnostically valuable even in situations when there is USG findings that are confirming FTAs or there is no important major fetal or placental anomaly detected in MCFs.

Placental pathology, perinatal death, neonatal outcome, and neurological development: a systematic review

BACKGROUND

The placenta plays a crucial role during pregnancy for growth and development of the fetus. Less than optimal placental performance may result in morbidity or even mortality of both mother and fetus. Awareness among pediatricians, however, of the benefit of placental findings for neonatal care, is limited.

OBJECTIVES

To provide a systematic overview of the relation between placental lesions and neonatal outcome.

DATA SOURCES

Pubmed database, reference lists of selected publications and important research groups in the field.

STUDY APPRAISAL AND SYNTHESIS METHODS

We systematically searched the Pubmed database for literature on the relation between placental lesions and fetal and neonatal mortality, neonatal morbidity and neurological outcome. We conducted three separate searches starting with a search for placental pathology and fetal and neonatal mortality, followed by placental pathology and neonatal morbidity, and finally placental pathology and neurological development. We limited our search to full-text articles published in English from January 1995 to October 2013. We refined our search results by selecting the appropriate articles from the ones found during the initial searches. The first selection was based on the title, the second on the abstract, and the third on the full article. The quality of the selected articles was determined by using the Newcastle-Ottawa Quality Assessment Scale.

RESULTS

Placental lesions are one of the main causes of fetal death, where placental lesions consistent with maternal vascular underperfusion are most important. Several neonatal problems are also associated with placental lesions, whereby ascending intrauterine infection (with a fetal component) and fetal thrombotic vasculopathy constitute the greatest problem.

CONCLUSIONS

The placenta plays a key role in fetal and neonatal mortality, morbidity, and outcome. Pediatricians should make an effort to obtain the results of placental examinations.

[Evaluation of intrauterine death: importance of examination of fetal, placental and maternal factors]

AIMS

Intrauterine death is a multifactorial major complication during pregnancy. In this retrospective analysis the pathological anatomical findings of fetuses and placentas as well as maternal factors were evaluated.

MATERIAL AND METHODS

A retrospective screening of post-mortem examinations, corresponding placental examinations and clinical data on maternal status (1998-2008) was carried out. A classification of all findings was made with the ReCoDe system and induced abortions and cases with incomplete data were excluded from the study.

RESULTS

A total of 84 pregnancies involving 87 fetuses (9 siblings) were evaluated. The median gestation age was 20 weeks (range 12-41). The evaluation based on the ReCoDe system revealed that intrauterine death was mainly associated with placental diseases (n = 63) and to a lesser extent with fetal malformations (n = 15) or maternal diseases (n = 4). Idiopathic cases were rare (n = 2).

CONCLUSIONS

Placental examination is important for explaining intrauterine death because in most cases an association with placental diseases can be found but fetal malformation and maternal diseases must be taken into account.

Twin pregnancies with single fetal death: analysis of 38 cases

The objective of this study is to evaluate fetal and maternal outcomes of twin pregnancies with intrauterine single fetal death. In 13 cases, intrauterine death of one fetus was found during the first trimester; in 25 cases, it was found after the first trimester. Obstetric complications and fibrinogen levels were compared. There were no significant differences in the number of preterm delivery, preeclampsia, and intrauterine growth restriction and there were significant differences in gestational age at delivery and birth weight between groups. Coagulation disorders did not occur. The risk for adverse pregnancy outcomes with a single fetal death during and after the first trimester is similar.

Unilateral uterine ischemia/reperfusion-induced bilateral fetal loss and fetal growth restriction in a murine model require intact complement component 5

The role of complement in ischemia/reperfusion-induced fetal growth restriction and fetal loss is unknown. C5-deficient or wild type timed-pregnant mice were subjected to unilateral uterine ischemia/reperfusion on gestation day 13, either by (1) partial flow restriction by right ovarian artery clamping for 30 min, or (2) total flow restriction by clamping both ovarian and uterine arteries for 5 min. Ischemia/reperfusion-challenged pregnancy outcomes were compared to sham-operated controls 5 days later. Ischemia/reperfusion-treated wild type mice exhibited significantly increased bilateral fetal loss, which was greater in total flow restriction than in partial flow restriction, and decreased fetal weights, which were the same in total flow restriction and partial flow restriction for the surviving fetuses. Placental weights were unchanged by treatments. Ischemia/reperfusion increased uterine, but not placental, myeloperoxidase activity, which correlated with fetal loss. In contrast, C5-deficient mice were protected from both fetal growth restriction and fetal loss, and exhibited no increase in myeloperoxidase activity. These results demonstrate that unilateral uterine ischemia/reperfusion results in bilateral fetal loss and fetal growth restriction, mediated by a systemic mechanism. In the current model, this pathological process is completely dependent on intact complement component 5.

Histological chorioamnionitis is increased at extremes of gestation in stillbirth: a population-based study

Objective. To determine the incidence of histological chorioamnionitis and a fetal response in stillbirths in New South Wales (NSW), and to examine any relationship of fetal response to spontaneous onset of labour and to unexplained antepartum death. Study Design. Population-based cohort study. Setting. New South Wales Australia. Population. All births between 2002 and 2004 with stillbirths reviewed and classified by the state perinatal mortality review committee. Methods. Record linkage of the Midwives Data Collection and the Perinatal Death Database including placental histopathology and standardised cause of death classification. Results. 952 stillbirths were included. The incidence of histopathological chorioamnionitis was 22.6%, with a bimodal distribution. A fetal inflammatory response was present in 10.1% and significantly correlated with spontaneous onset of labour. The absence of a fetal inflammatory response was strongly associated with unexplained antepartum death. Conclusions. The increased incidence of histological chorioamnionitis at extremes of gestation is confirmed in the largest dataset to date using population data. This has important implications for late gestation stillbirth as the percentage of unexplained stillbirths increases near term.

Prenatal smoking among adolescents and risk of fetal demise before and during labor

STUDY OBJECTIVE

To investigate the relationship between smoking during pregnancy and the occurrence of stillbirth phenotypes among adolescent mothers.

DESIGN

Retrospective cohort

SETTING

Singleton births in Missouri from 1978 through 1997.

PARTICIPANTS

Two groups of "younger" (<15 years) and "older" (15-19 years) adolescent mothers were compared to "mature" mothers (age 20-24 years).

MAIN OUTCOME MEASURES

Cox Proportional Hazards Regression models generated adjusted risk estimates of the association between intrauterine nicotine exposure and the risk of total, antepartum, and intrapartum stillbirth in each age group.

RESULTS

Approximately 32% (N=205,887) of the total 633,849 singleton births analyzed were among adolescent mothers. The overall prevalence of smoking was 31.2%, with the lowest prevalence (14.1%) among the youngest mothers while older adolescents had the highest (31.7%). The risk for intrapartum stillbirth among smoking adolescents <15 years of age was twice the risk for older adolescent and mature mothers. The risk of intrapartum stillbirth among smokers decreased as maternal age increased: [adjusted hazard ratio (AHR), 95% confidence interval (CI) for young mothers: 4.0, 95%CI=0.6-28.7; for older adolescents AHR=1.5, 95%CI=1.1-2.1 and for mature mothers AHR=1.8, 95% CI=1.4-2.2], respectively.

CONCLUSIONS

In utero tobacco exposure has maternal age-related differential and lethal effects on the fetus. Young maternal age tends to potentiate these effects. There is a public health need to develop appropriate smoking cessation messages targeted specifically to this high risk group.

The risk factors for unexplained antepartum stillbirths in Scotland, 1994 to 2003

OBJECTIVE

To determine the factors contributing to unexplained antepartum stillbirth in Scotland.

STUDY DESIGN

A 10-year birth database in Scotland was used to compare the unexplained antepartum stillbirth with other birth outcomes. The sample unit was a pregnant mother with a gestational age of 20 weeks and above and with a fetal birth weight of 200 g and above.

RESULT

Maternal age of 35 years and above, lower deprivation category, inaccessible area of residence, maternal smoking, maternal height of <160 cm and gestational age of above 39 weeks were significantly associated with unexplained antepartum stillbirth. In multivariable analysis only maternal age (adjusted odds ratio (OR): 1.8, confidence interval (CI): 1.1 to 3.0, P=0.02), smoking during pregnancy (adjusted OR: 2.0, CI: 1.1 to 3.5, P=0.02), and maternal height (adjusted OR: 1.4, CI: 1.1 to 1.8, P=0.01), remain significant. Screening of pregnancies based on these three risk factors had 4.2% sensitivity and 99.4% specificity. The prevalence of stillbirth for this population was 0.2%. A positive predictive value of only 1.2% implies that only 1 in 83 women with these three risk factors will have antepartum stillbirth. The remaining 82 will suffer needless anxiety and potentially diagnostic procedures.

CONCLUSION

Advanced maternal age, maternal smoking, and shorter maternal height were associated risk for unexplained antepartum stillbirth but screening based on these factors would be of limited value.

Placental findings contributing to fetal death, a study of 120 stillbirths between 23 and 40 weeks gestation

BACKGROUND

Intrauterine fetal death is an agonizing, often unpredictable event. Autopsies of stillborn fetuses, including placentas, are performed to clarify the cause of death. Autopsy results are not always easily understood by the patients or their healthcare providers.

OBJECTIVE

To evaluate placental causes of death in stillbirths based on autopsy and placental findings that are related to maternal underperfusion, fetal underperfusion, or inflammatory etiologies in hierarchical order.

METHODS

Retrospective review of 120 autopsy reports of singleton stillborn fetuses and placentas from 23 to 40 weeks of gestation.

RESULTS

Among the placental causes of death there were 54(51%) cases with direct cause or major contributor to death in the etiology of maternal vascular supply abnormalities, 28(26%) cases in the etiology of fetal vascular supply abnormalities and 13(12%) in the etiology of inflammatory lesions. Maternal vascular supply abnormalities were more common in preterm stillbirths and fetal vascular supply abnormalities were more common among term stillbirths. In 88% of stillbirths, the direct cause or a major contributor to death was found in the placentas. The incidence of unexplained death was 8%.

CONCLUSIONS

Pathological analysis of the placenta is essential for clarifying causes of stillbirths. Using specific simplified categories for abnormal placental findings may increase the benefits of the autopsy report.

Advanced maternal age and risk of antepartum and intrapartum stillbirth

AIM

We sought to assess the risk of antepartum and intrapartum stillbirth subtypes among women of advanced age.

METHODS

This is a retrospective cohort study using the Missouri maternally linked data containing births from 1978 to 1997. We examined the impact of maternal age on total, antepartum and intrapartum stillbirth across five maternal age group quintiles (20-24, 25-29, 30-34, 35-39 and >or=40) using mothers aged 20-24 years as the referent category. By means of the Cox proportional hazards regression models we obtained adjusted hazards ratios that quantified the magnitude of association between maternal age and the stillbirth subtypes.

RESULTS

The rates of antepartum and intrapartum stillbirth were greatest for older mothers (9.3/1000 and 1.2/1000 respectively) and lowest for gravidas aged 25-29 years (3.6/1000 and 0.8/1000 respectively). After adjusting for potentially confounding characteristics, older mothers still remained at greatest risk for antepartum and intrapartum stillbirth (adjusted hazards ratio = 3.6, 95% confidence interval = 2.9-4.4; and adjusted hazards ratio = 2.7, 95% confidence interval = 2.0-3.6 for antepartum and intrapartum stillbirth respectively). The risks for the two subtypes of stillbirth also increased with ascending maternal age in a dose-dependent pattern.

CONCLUSIONS

As the demographic distribution of pregnant women persistently shifts to the right, care-providers will be increasingly confronted with elevated risks for adverse fetal outcomes among older mothers. Our results confirm this phenomenon and add new findings in relation to the elevated risk for intrapartum stillbirth among mothers advanced for age.

The risk of intrapartum stillbirth among smokers of advanced maternal age

BACKGROUND/AIM

The effects of advanced maternal age and smoking in pregnancy on fetal survival have previously been reported. However, whether advanced maternal age modifies the relationship between smoking in pregnancy and intrapartum stillbirth remains unknown. We therefore set out to determine the impact of advanced maternal age (> or =35 years) on the association between smoking during pregnancy and intrapartum stillbirth by employing retrospective analysis of birth registry data.

METHODS

We used a cohort of singleton births in Missouri from 1978 through 1997 (N = 1,436,628) to compute the risk of total, antepartum, and intrapartum stillbirth in smoking mothers. We categorized mothers into two age groups: "younger" (<35 years), and "older" (> or =35 years). Non-smoking mothers age <35 years were the referent category. Cox regression models were used to generate independent measures of association between intrauterine tobacco exposure and the risk of total, antepartum, and intrapartum stillbirth in each age group.

RESULTS

A total of 5,772 counts of stillbirth were identified, yielding a stillbirth rate of 4.0 per 1,000. Approximately 33% (N = 1,900) occurred among older smokers resulting in a stillbirth rate of 9.1 per 1,000. The probability of intrapartum stillbirth was greatest among older smokers, followed by younger smokers and lowest among younger non-smokers (P < 0.01). As compared to non-smoking younger gravidas, younger smoking mothers had a 30% greater likelihood for both antepartum and intrapartum stillbirth (adjusted hazard ratio [95% confidence interval]: 1.3 [1.2-1.4] and 1.3 [1.2-1.5], respectively). Among older smokers the risk for intrapartum stillbirth was three times that of the referent group (adjusted hazard ratio: 3.2, 95% confidence interval: 2.2-4.5).

CONCLUSIONS

The risk of intrapartum stillbirth associated with smoking in pregnancy is potentiated by the age of the mother. This information will help policy makers develop targeted smoking cessation campaigns and positively impact quit rates in older mothers.

Chorioamnionitis and fetal response in stillbirth

OBJECTIVE

The purpose of this study was to determine the incidence of chorioamnionitis and fetal inflammatory response in a stillborn cohort and the relationship of fetal response to spontaneous labor, unexplained antepartum death, and spontaneous preterm death.

STUDY DESIGN

In a 15-year hospital cohort study, placental histopathologic evidence, labor onset, gestation, and cause of death classification data were analyzed.

RESULTS

Of 459 stillbirths, 428 stillbirths were included. The incidence of chorioamnionitis was 36.9%, with higher rates evident in early and late gestation. A fetal inflammatory response was present in 13.3% and correlated with spontaneous labor and very early spontaneous preterm death. The absence of a fetal response was associated with unexplained antepartum death.

CONCLUSION

The increased incidence of chorioamnionitis at extremes of gestation in stillbirth is novel and has important implications. The impact of a fetal response is gestation dependent and its absence is associated with unexplained antepartum death.

Prise en charge de la mort in utero : quel bilan proposer?

OBJECTIVE

To assess the value of para-clinical exams prescribed in case of in utero foetal death, to result in the establishment of a new algorithm of diagnostic tests.

MATERIALS AND METHODS

A retrospective analysis on a series of 106 stillbirths gathered between September 1989 and December 1998 in the obstetrical and gynaecological department of the Lausanne University Hospital which is a tertiary centre. Stillbirth was defined as foetal death occurring as from the date of foetal viability. Thus, only pregnancies from 24 weeks and onwards were included in this series. We excluded all stillbirths occurring during medical termination of pregnancy and cases with incomplete data files. The Fretts' classification was used. The different exams asked by the physician were screened and we analysed their pertinence to determine the aetiological diagnosis for each case. The search for significant risk factors was also taken into account. We compared our management of in utero foetal death with data from the literature to propose a new algorithm.

RESULTS

The aetiology of in utero foetal death could be attributed in ninety percent of the cases. The principal causes were in utero growth retardation (19.8%), foetal congenital and chromosomal anomalies (18.9%), infections (15.1%), placental abruption (7.5%), preeclampsia (5.6%), maternal diabetes (3.8%). The remaining 18.9% are divided in to miscellaneous causes. In 10.4% of the cases we could not find any explanation to the death of the foetus. The exams that yielded the most information when done were: foetal autopsy which was abnormal in 92.7%, placental investigation which was abnormal in 93% and the babygramme (X-ray of the foetal skeleton) which was abnormal in 53%. Maternal serology for infections was informative in 6.6% of the cases.

CONCLUSION

We present here a protocol for the diagnostic management of stillbirth which is differentiated according to the circumstances surrounding the event. This should prove useful to reduce superfluous tests.

The importance of quality of care in perinatal mortality: a case-control study in Chiapas, Mexico

BACKGROUND

This study was undertaken in order to ascertain the relative importance of different risk factors for perinatal mortality (PM) in a community of Chiapas, Mexico stressing the importance of antenatal and neonatal medical care.

METHODS

Cases were stillbirth and early neonatal death (END). Two children born in the same hospital and/or day as the case were randomly selected as controls, in Tapachula, Chiapas, Mexico. Socioeconomic, cultural, maternal, pregnancy, delivery, product and medical care factors were recorded. Two analyses were performed using multiple logistic regression: one for stillbirths, the other for END.

RESULTS

PM rate was 46.7/1000; 142 cases and 284 controls were studied. Fifteen cases were excluded due to congenital malformations; 62 stillbirth and 65 END were analyzed. For stillbirth, pregnancy-delivery and maternal medical care factors resulted in the most strongly associated risk factors for PM (OR=27.5 95% CI 6.4-116.8), and within this index insufficient prenatal care had the strongest impact on PM (%population attributable risk (%PAR)=24%). For END, fetal conditions and the newborn medical care index had the strongest association with PM (OR=9.5 95% CI 1.5-60.3), and within the index inappropriate medical care of the newborn (%PAR=27%) was the most important variable.

CONCLUSIONS

Our results support the fact that insufficient prenatal care and failure to comply with the standards of care for labor, delivery and for the care of the newborn are strong predictors of PM.

Identification of the causes of intrauterine death during 310 consecutive autopsies

OBJECTIVE

Evaluation of causes of death in stillborn infants.

METHODS

During a five-year period, 310 consecutive autopsies of stillborn infants were performed using a standardized protocol with systematic examination of all major cranial, thoracic and abdominal organs including microscopic examination.

RESULTS

In 71%, the intrauterine death (ID) occurred up to the end of the 37th week of gestation. Thirty-seven percent (115/310) stillbirths represented with maceration and about one-half with minor or major malformations. Thirty-one percent (53/171) of them were responsible for intrauterine death. In 83% (44/53), the intrauterine death of the malformed fetus occurred before the end of 37th week of gestation, most of them (48/53, 90.6%) were small for gestational age infants. In 75.5% (234/310), the placental villous tree and the umbilical cord represented pathologic conditions. In 191 cases (61.1%), utero-placental pathology was responsible for intrauterine death. Intrauterine infections and traumatic lesions were accompanied by intrauterine death in 2.2 and 1.3%, respectively. In 15.2%, unexplained intrauterine death (because of severe maceration, the placenta was not available for autopsy or insufficient clinical data) occurred.

CONCLUSIONS

Perinatal autopsy may be valuable in three ways: the confirmation of ante-mortem diagnoses; the identification of unexpected disorders; and exclusion of other (perhaps inheritable) conditions which might be have caused the intrauterine death. Clinically valuable information, obtained from the autopsy, can be improved by high autopsy rate and performing perinatal necropsies by specially trained pathologists.

Management of single fetal demise in a multiple gestation

Intrauterine fetal demise of 1 twin in a multiple gestation is a complex clinical situation. Chorionicity, gestational age at diagnosis, problems specific to the pregnancy, and the emotional needs of the patient can impact management. Strategies to optimize outcomes may include a multidisciplinary team approach and fetal surveillance. The following article reviews (1) adverse fetal and neonatal outcomes associated with intrauterine fetal demise of 1 twin, (2) the potential maternal impact, and (3) the strategies to possibly prevent poor outcomes. It is important to remember that even the most vigilant care may not avoid adverse sequelae in a portion of at-risk pregnancies.

The relationship between placental histopathology findings and perinatal outcome in preterm infants

OBJECTIVE

To determine the correlation between placental histopathology findings and perinatal outcome in preterm infants.

METHODS

Placental histopathology in 774 neonates delivered at 24-32 weeks between 1992 and 2000 was classified as follows: 254 (33%) had histological chorioamnionitis, 263 (34%) had coagulation-related lesions, 228 (30%) had vasculopathy. Perinatal outcome was compared between cases positive and negative for each histopathological classification.

RESULTS

Histological chorioamnionitis occurred in 46% of cases with premature rupture of membranes and 45% with preterm labor. Positivity versus negativity for histological chorioamnionitis was associated with earlier presentation (191 vs. 205 days, p = 0.0001) and delivery (199 days vs. 209 days, p = 0.0001), increased risk of intraventricular hemorrhage (71% vs. 23%, p = 0.001, odds ratio (OR) 2.2), bronchopulmonary dysplasia (26% vs. 15%, p = 0.0001, OR 2), retinopathy (36% vs. 24%, p = 0.001, OR 1.8), neonatal sepsis (28% vs. 13%, p = 0.0001, OR 2.5) and neonatal death (12% vs. 7%, p = 0.012, OR 2). Vasculopathy versus no vasculopathy was associated with decreased birth weight (1245 g vs. 1341 g, p = 0.011), decreased Apgar score at 5 min (20% vs. 13%, p = 0.011, OR 1.7) and necrotizing enterocolitis (6% vs. 2%, p = 0.001, OR 4). Cases positive for coagulation-related lesions correlated only with necrotizing enterocolitis (5% vs. 2%, p = 0.02, OR 2.6).

CONCLUSIONS

The presence of histological chorioamnionitis significantly increases the risk of earlier delivery and neonatal mortality. Vascular and coagulation placental findings increase the risk of necrotizing enterocolitis.

Costs and consequences of comprehensive stillbirth assessment

OBJECTIVE

The purpose of this study was to determine the consequences and costs of comprehensive stillbirth assessment.

STUDY DESIGN

Through reconstruction, we determined what consequences arise from assessment in the first 1477 stillborn pregnancies that were referred to the Wisconsin Stillbirth Service Program. Economic costs of stillbirth assessment were derived from real-time studies of those who performed the analyses and the costs of materials that were consumed.

RESULTS

When comprehensive, nonselective analysis is performed, new information that is relevant to recurrence risk estimation, prenatal diagnosis recommendation, or preconceptual, prenatal, perinatal, or neonatal treatment will arise in 51% of stillborn infants. The real cost of such assessment is approximately $1450 per assessment, or approximately $12 per cared-for pregnancy.

CONCLUSION

Substantial relevant information can be learned from stillbirth assessment at a modest economic cost. Programs that can provide comprehensive stillbirth assessment services should become part of routine pregnancy care.

Hypoplasia of medullary arcuate nucleus in unexpected late fetal death (stillborn infants): a pathologic study

OBJECTIVES

To evaluate the frequency, morphology, and pathogenesis (primary or secondary) of the abnormally developed medullary arcuate nucleus (ARCn) in stillbirths.

METHODS

We examined 26 stillbirths (24 antepartum, 2 intrapartum) that had a gestational age between 25 and 40 weeks and a normal karyotype. All of the stillborns were described as well-developed, with body length and weight proportional to their gestational age. Each case was submitted to complete autopsy examination, which included a systematic gross and microscopic evaluation of the body, the placental disk, and the umbilical cord and membranes. The brainstem was the particular focus of the histologic examination. The study of the various nuclei (nucleus hypoglossus, dorsal vagus motor nucleus, tractus solitarii nucleus, nucleus ambiguus, trigeminal tractus and nucleus, arcuate nucleus, and ventrolateral reticular formation and its neurons and parabrachial/Kölliker-Fuse complex) was performed on transversal serial sections through the entire pons and medulla oblongata. The histologic analysis was supplemented by volumetric reconstruction and immunohistochemical detection of both apoptosis and proliferating cell nuclear antigen.

RESULTS

Histologic examination showed abnormalities of the medulla oblongata ARCn in 9 fetuses (35%). In 8, a marked hypoplasia was evident, characterized by a volume reduction of the nucleus accompanied by neuronal depletion, whereas in 1 fetus the nucleus was completely absent (agenesis). The absence of gliosis, the negativity of the proliferating cell nuclear antigen analysis, and the similarities in apoptotic indices between the hypoplastic and well-developed arcuate are in keeping with a primary developmental defect. This anomaly is frequently associated with hypoplasia of the reticular formation and chronic hypoxia.

CONCLUSIONS

A high frequency of hypoplasia of the ARCn occurs in fetuses who have died "sine causa," ie, in a similar manner to that observed in sudden infant death syndrome. Chemoreceptors, although not involved in reflexogenic oxygenation in fetal life, become of vital importance intrapartum and postpartum; therefore, whenever impaired in the course of development, chemoreceptors may underlie cardioventilatory abnormalities critical to sudden infant death syndrome.

Mutations in coagulation factors in women with unexplained late fetal loss

BACKGROUND

Factor V and prothrombin-gene mutations are independent risk factors for venous thrombosis; it is debated whether a mutation in the gene encoding methylenetetrahydrofolate reductase, an enzyme involved in homocysteine metabolism, also increases the risk of venous thrombosis. Whether any of these mutations is associated with an increased risk of late fetal death is not known.

METHODS

We studied 67 women with a first episode of unexplained late fetal loss (fetal death after 20 weeks or more of gestation) and 232 women who had had one or more normal pregnancies and no late fetal losses. All the women were tested for the presence of three gene mutations. Women with other thrombophilic conditions were excluded from the study.

RESULTS

Eleven of the 67 women with late fetal loss (16 percent) and 13 of the 232 control women (6 percent) had either the factor V or the prothrombin mutation. The relative risks of late fetal loss in carriers of the factor V and prothrombin mutations were 3.2 (95 percent confidence interval, 1.0 to 10.9) and 3.3 (95 percent confidence interval, 1.1 to 10.3), respectively. Thirteen percent of the women whose fetuses died and 20 percent of the control women were homozygous for the mutation in the methylenetetrahydrofolate reductase gene (relative risk, 0.8; 95 percent confidence interval, 0.5 to 1.2).

CONCLUSIONS

Both the factor V and the prothrombin mutations are associated with an approximate tripling of the risk of late fetal loss.