Altered Levels of Decidual Immune Cell Subsets in Fetal Growth Restriction, Stillbirth, and Placental Pathology.

Immune cells are critically involved in placental development and functioning, and inadequate regulation of the maternal immune system is associated with placental pathology and pregnancy complications. This study aimed to explore numbers of decidual immune cells in pregnancies complicated with fetal growth restriction (FGR) and stillbirth (SB), and in placentas with histopathological lesions: maternal vascular malperfusion (MVM), fetal vascular malperfusion (FVM), delayed villous maturation (DVM), chorioamnionitis (CA), and villitis of unknown etiology (VUE). Placental tissue from FGR (n = 250), SB (n = 64), and healthy pregnancies (n = 42) was included. Histopathological lesions were classified according to criteria developed by the Amsterdam Placental Workshop Group. Tissue slides were stained for CD68 (macrophages), CD206 (M2-like macrophages), CD3 (T cells), FOXP3 [regulatory T (Treg) cells], and CD56 [natural killer (NK) cells]. Cell numbers were analyzed in the decidua basalis using computerized morphometry. The Mann-Whitney U-test and Kruskal Wallis test with the Dunn's as post-hoc test were used for statistical analysis. Numbers of CD68+ macrophages were higher in FGR compared to healthy pregnancies (p < 0.001), accompanied by lower CD206+/CD68+ ratios (p < 0.01). In addition, in FGR higher numbers of FOXP3+ Treg cells were seen (p < 0.01) with elevated FOXP3+/CD3+ ratios (p < 0.01). Similarly, in SB elevated FOXP3+ Treg cells were found (p < 0.05) with a higher FOXP3+/CD3+ ratio (p < 0.01). Furthermore, a trend toward higher numbers of CD68+ macrophages was found (p < 0.1) in SB. Numbers of CD3+ and FOXP3+ cells were higher in placentas with VUE compared to placentas without lesions (p < 0.01 and p < 0.001), accompanied by higher FOXP3+/CD3+ ratios (p < 0.01). Elevated numbers of macrophages with a lower M2/total macrophage ratio in FGR suggest a role for a macrophage surplus in its pathogenesis and could specifically indicate involvement of inflammatory macrophages. Higher numbers of FOXP3+ Treg cells with higher Treg/total T cell ratios in VUE may be associated with impaired maternal-fetal tolerance and a compensatory response of Treg cells. The abundant presence of placental lesions in the FGR and SB cohorts might explain the increase of Treg/total T cell ratios in these groups. More functionality studies of the observed altered immune cell subsets are needed.

More Maternal Vascular Malperfusion and Chorioamnionitis in Placentas After Expectant Management vs. Immediate Delivery in Fetal Growth Restriction at (Near) Term: A Further Analysis of the DIGITAT Trial.

Objective: Management of late fetal growth restriction (FGR) is limited to adequate fetal monitoring and optimal timing of delivery. The Disproportionate Intrauterine Growth Intervention Trial At Term (DIGITAT) trial compared induction of labor with expectant management in pregnancies at (near) term complicated by suspected FGR. Findings of the DIGITAT trial were that expectant monitoring prolonged pregnancy for 10 days and increased birth weight with only 130 grams. This resulted in more infants born below the 2.3rd percentile compared to induction of labor, respectively, 12.5% in induction of labor and 30.6% in expectant monitoring group. The main placental lesions associated with FGR are maternal vascular malperfusion, fetal vascular malperfusion, and villitis of unknown etiology. We investigated whether placentas of pregnancies complicated with FGR in the expectant monitoring group reveal more and more severe pathology due to pregnancy prolongation. Material and methods: The DIGITAT trial was a multicenter, randomized controlled trial with suspected FGR beyond 36 + 0 weeks. We now analyzed all available cases (n = 191) for placental pathology. The macroscopic details were collected and histological slides were recorded and classified by a single perinatal pathologist, blinded for pregnancy details and outcome. The different placental lesions were scored based on the latest international criteria for placental lesions as defined in the Amsterdam Placental Workshop Group Consensus Statement. Results: The presence of maternal vascular malperfusion and chorioamnionitis were higher in the expectant management group (p < 0.05 and p < 0.01, respectively). No differences in placental weight and maturation of the placenta between the induction of labor and the expectant management group were seen. Fetal vascular malperfusion, villitis of unknown etiology and nucleated red blood cell count did not differ between the groups. Conclusion: Expectant management of late FGR is associated with increased maternal vascular malperfusion and chorioamnionitis. This may have implications for fetal and neonatal outcome, such as programming in the developing child influencing health outcomes later in life.

Paneth cells in the developing gut: when do they arise and when are they immune competent?

BACKGROUND: Little is known about the perinatal development of Paneth cells (PCs) during gestation and the relation with necrotizing enterocolitis (NEC). We aimed to investigate when PCs arise and when they become immune competent during gestation. METHODS: We included 57 samples of ileum tissue of fetuses/infants with a gestional age (GA) between 9 and 40 wk taken as part of a standard autopsy procedure. Hematoxylin-eosin staining and anti-human defensin 5 immunohistochemistry were performed. We performed a semi-quantitative assessment of (immune-competent) PC numbers per 10 crypts per tissue section per GA. RESULTS: The number of PCs and the number of immune-competent PCs increased with increasing GA (Spearman's ρ = 0.41, P = 0.002 and ρ = 0.61, P < 0.001, respectively). Whereas significantly higher PC numbers were observed after 37 wk gestation (median 7, range 0-12) compared to preterm infants (median 0, range 0-15; P = 0.002), we counted higher numbers of immune-competent PCs already in infants with GA above 29 wk (median 6, range 0-18) compared to infants with GA under 29 wk (median 2, range 0-9; P < 0.001). CONCLUSION: The significant increase of immune-competent PCs starting from a GA of 29 wk mimics the rise in incidence of NEC during a similar postmenstrual age in preterm infants.

Thyroid function testing in women who had a stillbirth.

CONTEXT: Thyroid dysfunction is thought to be associated with stillbirth. Therefore, thyroid function is often recommended in the diagnostic investigations for stillbirth. OBJECTIVE: We aimed to evaluate the added value of thyroid function testing in the diagnostic investigations for stillbirth. DESIGN AND PATIENTS: A nationwide multicentre prospective cohort study in 1025 women who suffered stillbirth >20 weeks of gestation performed between 2002 and 2008. In each woman, an extensive diagnostic work-up was performed, including placental examination and autopsy. TSH and FT4 values below the 2·5th percentile or above the 97·5th percentile according local laboratory reference values were regarded as abnormal. Women with a history of thyroid disease were evaluated separately. MAIN OUTCOME MEASURES: Thyroid function abnormalities in women with stillbirth. RESULTS: Of 1025 included women, 21 had a history of thyroid disease (2%). In the 875 with TSH and FT4 results and no history of thyroid disease, 10% had hypothyroxinemia, 4·6% subclinical hypothyroidism, 1·6% overt hypothyroidism and 1·5% subclinical hyperthyroidism. Women with a subclinical hyperthyroidism more often had a foetal death caused by foetal hydrops: 23% vs 2·9% (adjusted OR 10·3, 95% CI 2·5-42). CONCLUSIONS: Women with a stillbirth had a slightly higher prevalence of overt hypothyroidism, subclinical hypothyroidism and hypothyroxinaemia compared to previous studies on thyroid dysfunction in pregnant women. Given the absence of a strong associations with the cause of stillbirth, and no demonstrated beneficial effects of treating thyroid dysfunction in these women, routine screening after stillbirth is not justified.

Classification of substandard factors in perinatal care: development and multidisciplinary inter-rater agreement of the Groningen-system.

BACKGROUND: Perinatal audit is an established method for improving the quality of perinatal care. In audit meetings substandard factors (SSF) are identified in cases of perinatal mortality and morbidity. To our knowledge there is no classification system specifically designed for the classification of substandard factors. Such a classification may help to standardise allocation of substandard factors to categories. This will help to prioritise, guide and implement actions in quality improvement programs. METHODS: A classification system of 284 substandard factors (SSF) identified in perinatal audit meetings between 2007 and 2011 was drawn up using the WHO Conceptual Framework for the International Classification for Patient Safety as a starting point. Discussions were held on inter-rater disagreements, inclusion of items, format and organisation and definitions of the main- and subcategories. A guideline was developed. An independent multidisciplinary group tested the classification. Independent of inter-rater agreement the allocations to categories were counted. For the counts in the subcategories one and two, we used the allocations in the main category as reference. The chance corrected agreement between classifiers was tested with Cohen's kappa statistic. RESULTS: The classification consists of 9 main categories with one or two subcategories. The main categories are (1) Equipment and Materials, (2) Medication, (3) Additional tests/ investigations, (4) Transportation , (5) Documentation, (6) Communication, (7) Medical practice, (8) Other and (9) non classifiable. Of 3663 allocations by 13 classifiers 1452 SSF's were allocated (40%) to 'medical practice' and 1247 (34%) to 'documentation'. 118 (3%) times SSF's were not classifiable, mainly due to unclear phrasing of the SSF. The chance corrected agreement of 284 substandard factors in the main category was 0.68 (95% CI 0.66-0.70) and 0.57 (95% CI 0.54-0.59) for the CDG and the IGD respectively. CONCLUSIONS: Classifying substandard factors has given insight into problem area's in perinatal care and can give direction to medical, political and financial quality improvement measures. The Groningen-system has well defined categories and subcategories and the guidelines and examples are clear. The multidisciplinary inter-rater agreement is moderate to good. Improvement of the phrasing of the substandard factors is expected to improve inter-rater agreement.

Infant's Age Influences the Accuracy of Rectal Suction Biopsies for Diagnosing of Hirschsprung's Disease.

BACKGROUND & AIMS: Hirschsprung's disease (HD) is a rare birth defect of the distal colon. Analysis of rectal suction biopsy (RSB) is considered to be the most reliable method for its diagnosis in infants. However, the diagnostic accuracy of RSB analysis could be affected by the patient's age, possibly because of rapid development of the enteric nervous system in the first weeks after birth. Because there is a trend toward testing for HD at early ages, we aimed to determine whether the diagnostic accuracy of RSB analysis is associated with the patient's age. METHODS: We performed a retrospective analysis of all patients from whom 1 or more RSBs were analyzed from 1975 through 2011 (529 RSBs from 441 patients). Outcomes of RSB analyses were categorized as positive, inconclusive, or negative for HD. Primary diagnoses, based only on RSB, were compared with final diagnoses made after at least 1 year of clinical follow-up. Age at time of RSB analysis was corrected for the gestational age. By using these criteria, we determined the diagnostic accuracy of RSB analysis for different age groups. RESULTS: RSB analysis identified HD in patients with sensitivity values of 46% (patients -45 to 7 days old), 47% (8-22 days old), and 62% (23-39 days old) (corrected for gestational age). The average sensitivity with which RSB analysis identified HD in patients older than 39 days was 88%. RSB identified HD in patients younger than 39 days old with significantly lower sensitivity than in older patients (50% vs 88%, P < .001). The specificity with which RSB identified infants without HD was not affected by age (average 95%). Of all RSBs, 11% were inconclusive for the diagnosis of HD. CONCLUSIONS: RSB analysis identifies HD in patients younger than 39 days old with only 50% sensitivity. Moreover, RSBs obtained from younger patients often lead to inconclusive outcomes and require additional biopsies. We propose that for infants suspected of HD at these ages, a noninvasive technique, such as anorectal manometry, should be used for a primary diagnosis. RSB should thereafter be used to confirm the diagnosis when the infant is older than 39 days.

Adverse pulmonary vascular remodeling in the Fontan circulation.

BACKGROUND: The Fontan circulation is a palliation for patients with a functionally univentricular heart. It is characterized by gradual attrition over time. An increase in pulmonary vascular resistance could be a key factor in the long-term failure of the Fontan circulation. In this study we aimed to identify pulmonary vascular remodeling in patients with a Fontan circulation. METHODS: Pulmonary vascular histomorphometric analysis and immunohistochemistry were performed in lung tissue obtained at autopsy from 12 Fontan patients. These patients had died either peri-operatively (Group A: death during or <15 days after Fontan completion; n = 5) or in mid to long-term follow-up (Group B: death >5 years after Fontan completion; n = 7). Two age-matched control groups (n = 10 and n = 14, respectively) were included. RESULTS: Intra-acinar pulmonary vessels in the Fontan Group B patients showed decreased medial thickness (p = 0.028) compared with age-matched controls, whereas intimal thickness was increased (p = 0.002). Intimal thickness in the Fontan Group B patients correlated with age at death (r = 0.964, p < 0.001) and with the length of time that the Fontan circulation had been in place (r = 0.714, p = 0.036). Immunohistochemistry revealed a reduction of vascular smooth muscles cells in the medial layer of the intra-acinar pulmonary vessels. The eccentric intimal thickening was composed of mainly acellular fibrosis with collagen deposition. CONCLUSIONS: We observed a unique pattern of adverse pulmonary vascular remodeling in patients with a long-standing Fontan circulation who had died during follow-up. This remodeling pattern may play a major role in long-term attrition of the Fontan circulation.

In preterm infants, ascending intrauterine infection is associated with lower cerebral tissue oxygen saturation and higher oxygen extraction.

BACKGROUND: Placental lesions are associated with neurological morbidity but the mechanism leading to morbidity is unclear. To provide insight into such a possible mechanism, we determined whether placental lesions were associated with regional cerebral tissue oxygen saturation (rcSO2) and fractional tissue oxygen extraction (FTOE) in preterm infants during their first 5 d after birth. We hypothesized that as a result of cerebral hypoperfusion, rcSO2 would be lower and FTOE would be higher. METHOD: In a prospective, observational study of 42 preterm infants (gestational age <32 wk), the infants' placentas were examined for histopathology. We measured rcSO2 and transcutaneous arterial oxygen saturation (SpO2) on days 1-5. FTOE was calculated as FTOE = (transcutaneous SpO2 - rcSO2)/transcutaneous SpO2. RESULTS: Only three placentas showed no pathology. Ascending intrauterine infection (AIUI) (n = 16) was associated with lower rcSO2 and higher FTOE values on days 2, 3, and 4 (P ≤ 0.05). Other placental lesions were not associated with rcSO2 and FTOE. CONCLUSION: AIUI is associated with lower rcSO2, and higher FTOE shortly after birth. The effect it has on cerebral oxygenation might be the mechanism leading to neurodevelopmental problems.

The implementation of unit-based perinatal mortality audit in perinatal cooperation units in the northern region of the Netherlands.

BACKGROUND: Perinatal (mortality) audit can be considered to be a way to improve the careprocess for all pregnant women and their newborns by creating an opportunity to learn from unwanted events in the care process. In unit-based perinatal audit, the caregivers involved in cases that result in mortality are usually part of the audit group. This makes such an audit a delicate matter. METHODS: The purpose of this study was to implement unit-based perinatal mortality audit in all 15 perinatal cooperation units in the northern region of the Netherlands between September 2007 and March 2010. These units consist of hospital-based and independent community-based perinatal caregivers. The implementation strategy encompassed an information plan, an organization plan, and a training plan. The main outcomes are the number of participating perinatal cooperation units at the end of the project, the identified substandard factors (SSF), the actions to improve care, and the opinions of the participants. RESULTS: The perinatal mortality audit was implemented in all 15 perinatal cooperation units. 677 different caregivers analyzed 112 cases of perinatal mortality and identified 163 substandard factors. In 31% of cases the guidelines were not followed and in 23% care was not according to normal practice. In 28% of cases, the documentation was not in order, while in 13% of cases the communication between caregivers was insufficient. 442 actions to improve care were reported for 'external cooperation' (15%), 'internal cooperation' (17%), 'practice organization' (26%), 'training and education' (10%), and 'medical performance' (27%). Valued aspects of the audit meetings were: the multidisciplinary character (13%), the collective and non-judgmental search for substandard factors (21%), the perception of safety (13%), the motivation to reflect on one's own professional performance (5%), and the inherent postgraduate education (10%). CONCLUSION: Following our implementation strategy, the perinatal mortality audit has been successfully implemented in all 15 perinatal cooperation units. An important feature was our emphasis on the delicate character of the caregivers evaluating the care they provided. However, the actual implementation of the proposed actions for improving care is still a point of concern.

Evaluation of 1025 fetal deaths: proposed diagnostic workup.

OBJECTIVE: We sought to evaluate the contribution of different diagnostic tests for determining cause of fetal death. Our goal was to propose a workup guideline. STUDY DESIGN: In a multicenter prospective cohort study from 2002 through 2008, for 1025 couples with fetal death ≥20 weeks' gestation, an extensive nonselective diagnostic workup was performed. A panel classified cause and determined contribution of diagnostics for allocating cause. RESULTS: A Kleihauer-Betke, autopsy, placental examination, and cytogenetic analysis were abnormal in 11.9% (95% confidence interval [CI], 9.8-14.2), 51.5% (95% CI, 47.4-55.2), 89.2% (95% CI, 87.2-91.1), and 11.9% (95% CI, 8.7-15.7), respectively. The most valuable tests for determination of cause were placental examination (95.7%; 95% CI, 94.2-96.8), autopsy (72.6%; 95% CI, 69.2-75.9), and cytogenetic analysis (29.0%; 95% CI, 24.4-34.0). CONCLUSION: Autopsy, placental examination, cytogenetic analysis, and testing for fetal maternal hemorrhage are basic tests for workup after fetal death. Based on the results of these tests or on specific clinical characteristics, further sequential testing is indicated.

[Perinatal audit in the North of the Netherlands: the first 2 years]. / Perinatale audit Noord-Nederland: de eerste 2 jaar.

OBJECTIVE: Description of the implementation of local audit meetings and the identified substandard factors, points of special interest, actions for improvement and the opinion of the participating health care providers. DESIGN: Descriptive study. METHOD: A new organisation and methodology for perinatal mortality audit meetings was introduced in 15 collaborative structures in the northern part of the Netherlands in the period September 2007 to March 2010. During these multidisciplinary audit meetings, cases of perinatal mortality selected by the obstetric collaborative group were discussed in a structured way under the direction of an independent chairman. RESULTS: In total 64 audit meetings were held, in which 677 perinatal health care providers took part at least once, and 112 cases of perinatal death were evaluated. 163 substandard factors were identified. These included : not following the protocol, guideline, standard (31%) or usual care (23%) and insufficient documentation (28%) and communication between health care providers (13%). 442 actions to improve care were reported divided over: 'external collaboration' (15%), 'internal collaboration' (17%), 'practice management' (26%) and 'training and education' (10%). The most valued aspects of the audit meetings were: their multidisciplinary character, the collaborative search for substandard factors, their security, the learning effect and the positive effect on collaboration. CONCLUSION: Cases of perinatal mortality were discussed in all 15 perinatal collaborative structures in the northern part of the Netherlands. Substandard factors were identified, but further analysis of these factors merits attention. The participants concluded that the multidisciplinary approach and the collaboration during the audit meetings improved the cooperation between perinatal health care providers.

Neonatal myocardial infarction or myocarditis?

We report a 29 week-gestation preterm infant who presented during his second week of life with cardiogenic shock. Clinical presentation and first diagnostics suggested myocardial infarction, but echocardiographic features during follow-up pointed to a diagnosis of enteroviral myocarditis. The child died of chronic heart failure at 9 months of age. Autopsy showed passed myocardial infarction. No signs for active myocarditis were found. We discuss the difficulties in differentiating between neonatal myocardial infarction and myocarditis. Recognizing enteroviral myocarditis as cause for cardiogenic shock is of importance because of the therapeutic options.

Apoptosis and proliferation in first trimester trophoblast of further complicated and uncomplicated pregnancies related to maternal serum screening markers.

INTRODUCTION: Differences in proliferation and apoptosis in term trophoblast as well as maternal serum markers (MSM) for Down's syndrome in early pregnancy are related to adverse pregnancy outcomes. We investigated proliferation and apoptosis in first trimester chorionic villous sampling (CVS) as well as MSM and related these to pregnancy outcome. MATERIALS AND METHODS: We selected 51 samples of first trimester chorionic villi of pregnancies later complicated by hypertensive disorders (HD) (n=36) and intra-uterine growth restriction (IUGR) (n=15) with matched controls. Immunohistochemistry (cleaved caspase-3 for apoptosis and MIB-1 for proliferation) was performed. Apoptosis- (AI) and proliferation-index (PI) were determined and proliferation-apoptosis index (PA) was calculated by PI/AI. First trimester serum screening (n=39), samples taken at the time of CVS (n=108) or regular second trimester serum screening samples (n=99) were examined. RESULTS: The IUGR group compared to the hypertensive disorders group shows an increase of AI (p<0.05) and decrease in PA (p<0.03). Correlation is seen between PAPP-A and PI, AFP and AI and hCG and PA (all p<0.05). CONCLUSION: Proliferation and apoptosis differ already in first trimester placentas of pregnancies complicated by hypertensive disorders or IUGR. Serum screening markers show correlation with proliferation and apoptosis and a subsequent adverse pregnancy outcome.

Cost-effectiveness of a screening strategy for Q fever among pregnant women in risk areas: a clustered randomized controlled trial.

BACKGROUND: In The Netherlands the largest human Q fever outbreak ever reported in the literature is currently ongoing with more than 2300 notified cases in 2009. Pregnant women are particularly at risk as Q fever during pregnancy may cause maternal and obstetric complications. Since the majority of infected pregnant women are asymptomatic, a screening strategy might be of great value to reduce Q fever related complications. We designed a trial to assess the (cost-)effectiveness of a screening program for Q fever in pregnant women living in risks areas in The Netherlands. METHODS/DESIGN: We will conduct a clustered randomized controlled trial in which primary care midwife centres in Q fever risk areas are randomized to recruit pregnant women for either the control group or the intervention group. In both groups a blood sample is taken around 20 weeks postmenstrual age. In the intervention group, this sample is immediately analyzed by indirect immunofluorescence assay for detection of IgG and IgM antibodies using a sensitive cut-off level of 1:32. In case of an active Q fever infection, antibiotic treatment is recommended and serological follow up is performed. In the control group, serum is frozen for analysis after delivery. The primary endpoint is a maternal (chronic Q fever or reactivation) or obstetric complication (low birth weight, preterm delivery or fetal death) in Q fever positive women. Secondary aims pertain to the course of infection in pregnant women, diagnostic accuracy of laboratory tests used for screening, histo-pathological abnormalities of the placenta of Q fever positive women, side effects of therapy, and costs. The analysis will be according to the intention-to-screen principle, and cost-effectiveness analysis will be performed by comparing the direct and indirect costs between the intervention and control group. DISCUSSION: With this study we aim to provide insight into the balance of risks of undetected and detected Q fever during pregnancy. TRIAL REGISTRATION: ClinicalTrials.gov, protocol record NL30340.042.09.

Prevalence of parental thrombophilic defects after fetal death and relation to cause.

OBJECTIVE: To estimate whether parental thrombophilic defects after fetal death, either acquired or inherited, were more prevalent than in the normal population and to estimate associations between these thrombophilic defects and different fetal death causes. METHODS: In a multicenter, prospective cohort study of 750 fetal deaths, we tested couples for antithrombin, protein C, total and free protein S, and von Willebrand factor (vWF) plasma levels. Mothers' values were compared with reference values in gestational age-matched healthy pregnant women, and fathers were compared with healthy men. Prevalence of factor V Leiden, prothrombin G20210A mutation, and lupus anticoagulant were compared with the normal population. A panel classified death cause. RESULTS: More women with fetal death had decreased antithrombin (16.8%, P<.001) and protein C (4.0%, P=.03) and increased vWF (15.5%, P<.001) plasma levels than healthy pregnant women (2.5%). However, compared with normal ranges in the nonpregnant population, we only observed more women with increased vWF (12.4%, P<.001). More fathers had decreased free protein S (6.3%, P<.001) and elevated vWF (12.1%, P<.001) than healthy men (2.5%). Prevalence of inherited thrombophilias was not higher in couples with fetal death than in the population. Neither inherited nor acquired maternal or paternal thrombophilic defects were associated with the main cause of death. Of placental causes, abruption and infarction were associated with acquired maternal defects. CONCLUSION: Except for vWF and paternal free protein S, acquired and inherited thrombophilic defects were not more prevalent after fetal death. Routine thrombophilia testing after fetal death is not advised. LEVEL OF EVIDENCE: II.

Diverse placental pathologies as the main causes of fetal death.

OBJECTIVE: To estimate the occurrence of placental causes of fetal death in relation to different gestational ages and their clinical manifestations during pregnancy. METHODS: In a prospective cohort study conducted from 2002 to 2006, we studied 750 couples with singleton intrauterine fetal death after 20 weeks of gestation. Cause of death was classified according to the Dutch Tulip cause of death classification for perinatal mortality. Differences between groups for categorical data were evaluated by the Fisher exact test or chi test. RESULTS: The main causes were placental pathology (64.9%), congenital anomaly (5.3%), infection (1.9%), other (4.8%), and unknown (23.1%). The contribution of causes differed over gestational age periods. At lower gestational age, placental and unknown were the most dominant causes of death (34.8% and 41.7%, respectively); at higher gestational age, the relative importance of an unknown cause decreased and a placental cause increased (16.5% and 77.6%) (P<.001). Placental bed pathology was observed in 33.6% of all fetal deaths, with the highest occurrence between 24 0/7 and 31 6/7 weeks and a strong decline after 32 weeks. In contrast, contribution of developmental placental pathology (17.6%) increased after 32 weeks of gestation (P<.001), as did umbilical cord complications (5.2%) and combined placental pathology (5.4%). Solitary placental parenchyma pathology was less frequent (3.1%). Hypertension-related disease was observed in 16.1% (95% confidence interval [CI] 13.6-19.0) of the cohort, small for gestational age fetuses in 37.9% (95% CI 34.1-41.7), and diabetes-related disease in 4.1% (95% CI 2.8-5.8). CONCLUSION: Most fetal deaths were caused by a variety of placental pathologies. These were related to gestational age, and their clinical manifestations varied during pregnancy. LEVEL OF EVIDENCE: II.

A multilayered approach for the analysis of perinatal mortality using different classification systems.

Many classification systems for perinatal mortality are available, all with their own strengths and weaknesses: none of them has been universally accepted. We present a systematic multilayered approach for the analysis of perinatal mortality based on information related to the moment of death, the conditions associated with death and the underlying cause of death, using a combination of representatives of existing classification systems. We compared the existing classification systems regarding their definition of the perinatal period, level of complexity, inclusion of maternal, foetal and/or placental factors and whether they focus at a clinical or pathological viewpoint. Furthermore, we allocated the classification systems to one of three categories: 'when', 'what' or 'why', dependent on whether the allocation of the individual cases of perinatal mortality is based on the moment of death ('when'), the clinical conditions associated with death ('what'), or the underlying cause of death ('why'). A multilayered approach for the analysis and classification of perinatal mortality is possible by using combinations of existing systems; for example the Wigglesworth or Nordic Baltic ('when'), ReCoDe ('what') and Tulip ('why') classification systems. This approach is useful not only for in depth analysis of perinatal mortality in the developed world but also for analysis of perinatal mortality in the developing countries, where resources to investigate death are often limited.

Cytogenetic analysis after evaluation of 750 fetal deaths: proposal for diagnostic workup.

OBJECTIVE: To estimate success rates for cytogenetic analysis in different tissues after intrauterine fetal death, and study selection criteria and value of cytogenetic testing in determining cause of death. METHODS: Cytogenetic analyses and the value of this test in determining cause by a multidisciplinary panel were studied in 750 fetal deaths. Morphologic abnormalities, small for gestational age (SGA), advanced maternal age (older than 35 years) and maceration were studied as selection criteria. RESULTS: Chromosomal abnormalities were observed in 13% of fetal deaths. Cytogenetic success rates were significantly higher for invasive testing (85%) than for postpartum tissue analysis (28%, P<.001). There were more abnormal chromosomes (38%) in fetal deaths with morphologic abnormalities than in those without (5%, P<.001). This was not observed for SGA (16% compared with 9.2%, P=.22) or for advanced maternal age (16.7% compared with 12.0%, P=.37). The posterior probability of a chromosomal abnormality in the absence of morphologic abnormalities was still 4.6%. Cytogenetic analysis was successful in 35% of severely macerated fetuses. We do not advise using these selection criteria, because the failure rate was high on postpartum tissues. Cytogenetic analysis was valuable in determining the cause in 19% of the fetal deaths. CONCLUSION: Parents should be counseled on aspects of cytogenetic analysis after fetal death. We advise performing nonselective invasive testing after fetal death and before labor for all fetal deaths.