Amniotic Fluid Embolism (AFE): A Review of the Literature Orientated on Two Clinical Presentations--Typical and Atypical

Background/Aim: Recently, a comparative study on the incidence of AFE has highlighted rather confusing results, showing that the complication is more than three times higher in North America than that in some European countries. In this paper, we put forward the hypothesis that this discrepancy is due to inaccurate diagnosis of non-classical form of AFE (atypical AFE). We also provide an outline of symptoms that characterize this type of AFE based on the analysis of all available case reports. Material and Methods: We searched Medline from 1969 (its inception) to 2011, using the key words “amniotic fluid embolism”. The search produced 1127 articles, including 208 case reports of AFE and other publications identified as eligible for our study (11 review articles and 6 population-based studies of the last few years). Moreover, we looked through the articles from the period before “inception of Medline” to find 178 earlier case reports. Full texts were analyzed. Results and Conclusions: (i) Worldwide, 447 cases of AFE have been reported, including 70 cases of atypical AFE (15.7%). (ii) Typical AFE is characterized by three clinical phases (cardiopulmonary collapse, clotting disorders and hemorrhages, multiorgan disturbances), whereas the atypical one shows lack of cardiopulmonary collapse as the initial presentation—the first to appear is obstetric hemorrhage and/or pulmonary and renal dysfunction. (iii) Four subclasses of atypical AFE were distinguished on the basis of case reports: uterine hemorrhage-type of AFE, ARDS as the only presentation of atypical AFE, paradoxical AFE, and cesarean section-related atypical AFEs.

Heparin and other anticoagulants in amniotic fluid embolism(AFE):Literature review and concept of the therapy

Aim: The objective of this study is to review all the reported outcomes of heparin application in amniotic fluid embolism (AFE) so far and to find out why, when and how heparin or other anticoagulants should be used in AFE. Material and methods: We searched Medline (from 1969 to 2011), using two key words: 1) amniotic fluid embolism;2) amniotic fluid embolism and heparin. The search for the former produced 1127 replies, of which 208 were case reports of AFE. In response to the other key word, there were 94 articles. We looked through all the articles, selecting those relevant for our study. Results: In the years 1969-2011, 208 AFE cases were reported. Heparin (unfractionated heparin) or low molecular weight heparin (LMWH) was applied in 20 cases (9.6%), being the main drug in 11 cases (5.3%) and in 6 cases as a component of spectacular treatment of AFE (surgical treatment and extracorporal membrane oxygenation). In one of these cases anithrombin (AT) with LMWH was used. In one patient heparin therapy was considered to be unsuccessful and hence recombinant plasminogen activator (rt-PA) was instituted. All the patients survived. Conclusions: 1) The attempts to use heparin in AFE could be defined as promising, although the number of treated patients is too small for conclusion;2) The postulate to use heparin at the very onset of AFE (a bolus of 10,000 U followed by monitored intravenous infusion) has serious justification: one of the pathways of AFE is the target for heparin (coagulation pathway).

Intralipid for Amniotic Fluid Embolism (AFE)?

In 1998 it was first showed that intravenous Intralipid could prevent or improve resuscitation from cardiovascular collapse by severe bupivacaine overdose in rats. Since then published examples now include toxicities related to verapamil, diltiazem, amlodipine, quetiapine and sertraline, haldoperidol, lamotrigine, olanzapine, propranolol, atenolol, nevibolol, doxepin, dosulepin, imipramine, amitriptyline, glyosphate herbicide, flecainide, venlafaxine, moxidectin, and others. Amniotic fluid embolism (AFE) is a rare but potentially catastrophic obstetric emergency. Despite earlier recognition and aggressive treatment, morbidity and mortality rates remain high. An estimated 5% - 15% of all maternal deaths in Western countries are due to AFE. The pathophysiology of AFE is not completely understood. AFE most commonly occurs during labor, delivery, or the immediate postpartum period. However, it has been reported to occur up to 48 h postpartum. Pulmonary hypertension and right heart strain/failure may be the result of physical amniotic fluid debris in the pulmonary vasculature or, perhaps more likely, result from circulating pulmonary vasoconstrictive mediators. Therapy with Intralipid in male rats resulted in 100% survival and prevented Pulmonary arterial hypertension-induced right ventricular failure by preserving right ventricular pressure and right ventricular ejection fraction and preventing right ventricular hypertrophy and lung remodeling. In preexisting severe Pulmonary arterial hypertension, Intralipid attenu-ated most lung and right ventricular abnormalities. The beneficial effects of Intralipid in Pulmonary arterial hypertension seem to result from the interplay of various factors, among which preservation and/or stimulation of angiogenesis, suppression and/or reversal of inflammation, fibrosis and hypertrophy, in both lung and right ventricular, appear to be major contributors. In conclusion, Intralipid not only prevents the development of Pulmonary arterial hypertension and right ventricular failure but also rescues preexisting severe Pulmonary arterial hypertension. Intralipid treatment is a new treatment for AFE (amniotic fluid embolism) which was never suggested before. Animal studies should be done in order to evaluate this new treatment modality.

Osteogenic differentiation of amniotic fluid mesenchymal stromal cells and their bone regeneration potential

In orthopedics, tissue engineering approach using stem cells is a valid line of treatment for patients with bone defects. In this context, mesenchymal stromal cells of various origins have been extensively studied and continue to be a matter of debate. Although mesenchymal stromal cells from bone marrow are already clinically applied, recent evidence suggests that one may use mesenchymal stromal cells from extra-embryonic tissues, such as amniotic fluid, as an innovative andadvantageous resource for bone regeneration. The use of cells from amniotic fluid does not raise ethical problems and provides a sufficient number of cells without invasive procedures. Furthermore, they do not develop into teratomas when transplanted, a consequence observed with pluripotent stem cells. In addition, their multipotent differentiation ability, low immunogenicity, and anti-inflammatory properties make them ideal candidates for bone regenerative medicine. We here present an overview of the features of amniotic fluid mesenchymal stromal cells and their potential in the osteogenic differentiation process. We have examined the papers actually available on this regard, with particular interest in the strategies applied to improve in vitro osteogenesis. Importantly, a detailed understanding of the behavior of amniotic fluid mesenchymal stromal cells and their osteogenic ability is desirable considering a feasible application in bone regenerative medicine.

Molecular and phenotypic characterization of human amniotic fluid cells and their differentiation potential

The main goal of the study was to identify a novel source of human multipotent cells, overcoming ethical issues involved in embryonic stem cell research and the limited availability of most adult stem cells. Amniotic fluid cells （AFCs） are routinely obtained for prenatal diagnosis and can be expanded in vitro; nevertheless current knowledge about their origin and properties is limited. Twenty samples of AFCs were exposed in culture to adipogenic, osteogenic, neurogenic and myogenic media. Differentiation was evaluated using immunocytochemistry, RT-PCR and Western blotting. Before treatments, AFCs showed heterogeneous morphologies. They were negative for MyoD, Myf-5, MRF4, Myogenin and Desmin but positive for osteocalcin, PPARgamma2, GAP43, NSE, Nestin, MAP2, GFAP and beta tubulin III by RT-PCR. The cells expressed Oct-4, Rex-1 and Runx-1, which characterize the undifferentiated stem cell state. By immunocytochemistry they expressed neural-glial proteins, mesenchymal and epithelial markers. After culture, AFCs differentiated into adipocytes and osteoblasts when the predominant cellular component was fibroblastic. Early and late neuronal antigens were still present after 2 week culture in neural specific media even if no neuronal morphologies were detectable. Our results provide evidence that human amniotic fluid contains progenitor cells with multi-lineage potential showing stem and tissue-specific gene/protein presence for several lineages.

Amniotic fluid： Source of trophic factors for the developingintestine

The gastrointestinal tract(GIT) is a complex system, which changes in response to requirements of the body. GIT represents a barrier to the external environment. To achieve this, epithelial cells must renew rapidly. This renewal of epithelial cells starts in the fetal life under the influence of many GIT peptides by swallowing amniotic fluid(AF). Development and maturation of GIT is a very complex cascade that begins long before birth and continues during infancy and childhood by breastfeeding. Many factors like genetic preprogramming, local and systemic endocrine secretions and many trophic factors(TF) from swallowed AF contribute and modulate the development and growth of the GIT. GIT morphogenesis, differentiation and functional development depend on the activity of various TF in the AF. This manuscript will review the role of AF borne TF in the development of GIT.

Amniotic fluid stem cell-based models to study the effects of gene mutations and toxicants on male germ cell formation

Male infertility is a major public health issue predominantly caused by defects in germ cell development. In the past, studies on the genetic regulation of spermatogenesis as well as on negative environmental impacts have been hampered by the fact that human germ cell development is intractable to direct analysis in vivo. Compared with model organisms including mice, there are fundamental differences in the molecular processes of human germ cell development. Therefore, an in vitro model mimicking human sperm formation would be an extremely valuable research tool. In the recent past, both human embryonic stem （ES） cells and induced pluripotent stem （iPS） cells have been reported to harbour the potential to differentiate into primordial germ cells and gametes. We here discuss the possibility to use human amniotic fluid stem （AFS） ceils as a biological model. Since their discovery in 2003, AFS cells have been characterized to differentiate into cells of all three germ layers, to be genomically stable, to have a high proliferative potential and to be non-tumourigenic. In addition, AFS cells are not subject of ethical concerns. In contrast to iPS cells, AFSs cells do not need ectopic induction of pluripotency, which is often associated with only imperfectly cleared epigenetic memory of the source cells. Since AFS cells can be derived from amniocentesis with disease-causing mutations and can be transfected with high efficiency, they could be used in probing gene functions for spermatogenesis and in screening for male reproductive toxicity.

Study of concentration of amniotic fluid Alpha-fetal protein in thalassemia fetus

Objective:To test the hypothesis that concentration of amniotic fluid alpha-fetal protein(AFAFP) is increased in thalassemia fetus.Methods:A total of 135 cases of amniocentesis admitted from July 2013 to December 2014 were included in this study.Among them 98 cases of normal fetuses were assigned into control group and 37 cases of thalassemia fetus were included as thalassemia fetus group.Alpha-fetoprotein levels detected by enzyme linked immunosorbent assay and the alpha-fetoprotein concentration were compared between the two groups.There is no significant difference in gestrational age between the two groups.Results:1.AFP concentration in thalassemia fetus group was significantly higher than that of normal control group [(1541.65±734.78) μg/mL vs.(2728.84± 1539.97) μg/mL ],and amniotic fluid AFP concentration was related to fetal thalassemia.2.AFAFP concentration in pureα-thalassemia fetus was higher than that of β thalassemia fetus or mixed αand was not significant.Conclusions:Concentration of a β thalassemia fetus,but the difference mniotic fluid alpha-fetal protein is increased in thalassemia fetus.AFP concentration inα-thalassemia fetus was higher than that of β thalassemia or mixed αand lore β thalassemia fetus but difference was not significance.Further studies are needed to exp the possible correlation between Down syndrome and biochemical markers of Thalassemia.

Phthalate Metabolites in Amniotic Fluid and Maternal Urine Samples

The objective of this study was to determine the concentrations of the metabolites of four selected phthalates, widely used industrial chemicals which possess endocrine-disrupting properties, in samples of amniotic fluid and maternal urine collected in the same day, in order to verify if the latter can be considered a measure of the fetal exposure. The quantitative determination of the metabolites was carried out by HPLC-MS/MS with isotopic dilution from 70 pregnant volunteers. Detectable concentrations of phthalates metabolites were found in amniotic fluids. As phthalate monoesters are excreted in the urine conjugated with glucuronic acid, an enzymatic hydrolysis is carried out before analysis. Amniotic fluids were tested with and without hydrolysis and only the free phthalate metabolites, not conjugated with glucuronic acid, were found. The concentration of metabolites after enzymatic hydrolysis in maternal urine is not correlated to those of amniotic fluids, but the free form concentrations are. These results suggest that only the free forms can cross the placenta. A significant number of mothers showed urine phthalate monoesters concentrations higher than non-pregnant women.

Human amniotic fluid stem cell therapy can help regain bladder function in type 2 diabetic rats

BACKGROUND Diabetes mellitus(DM)is a serious and growing global health burden.It is estimated that 80%of diabetic patients have micturition problems such as poor emptying,urinary incontinence,urgency,and urgency incontinence.Patients with diabetic bladder dysfunction are often resistant to currently available therapies.It is necessary to develop new and effective treatment methods.AIM To examine the therapeutic effect of human amniotic fluid stem cells(hAFSCs)therapy on bladder dysfunction in a type 2 diabetic rat model.METHODS Sixty female Sprague-Dawley rats were divided into five groups:Group 1,normal-diet control(control);group 2,high-fat diet(HFD);group 3,HFD plus streptozotocin-induced DM(DM);group 4,DM plus insulin treatment(DM+insulin);group 5,DM plus hAFSCs injection via tail vein(DM+hAFSCs).Conscious cystometric studies were done at 4 and 12 wk after insulin or hAFSCs treatment to measure peak voiding pressure,voided volume,intercontraction interval,bladder capacity,and residual volume.Immunoreactivities and/or mRNA expression of muscarinic receptors,nerve growth factor(NGF),and sensory nerve markers in the bladder and insulin,MafA,and pancreatic-duodenal homeobox-1(PDX-1)in pancreatic beta cells were studied.RESULTS Compared with DM rats,insulin but not hAFSCs treatment could reduce the bladder weight and improve the voided volume,intercontraction interval,bladder capacity,and residual volume(P<0.05).However,both insulin and hAFSCs treatment could help to regain the blood glucose and bladder functions to the levels near controls(P>0.05).The immunoreactivities and mRNA expression of M2-and M3-muscarinic receptors(M2 and M3)were increased mainly at 4 wk(P<0.05),while the number of beta cells in islets and the immunoreactivities and/or mRNA of NGF,calcitonin gene-related peptide(CGRP),substance P,insulin,MafA,and PDX-1 were decreased in DM rats(P<0.05).However,insulin and hAFSCs treatment could help to regain the expression of M2,M3,NGF,CGRP,substance P,MafA,and PDX-1 to near the levels of controls at 4 and/or 12 wk(P>0.05).CONCLUSION Insulin but not hAFSCs therapy can recover the bladder dysfunction caused by DM;however,hAFSCs and insulin therapy can help to regain bladder function to near the levels of control.

Changes of Nerve Growth Factor in Amniotic Fluid and Correlation with Ventriculomegaly

Objective To detect the change of nerve growth factor (NGF) level in human amniotic fluid during gestation, and to explore the relationship between this change and fetal ventriculo-megaly (VM). Methods The studied subjects (collected from 2004 to 2007) were divided into four groups, including the second-trimester pregnancy group (n=113), third-trimester pregnancy group (n=110), fetal cerebral VM group (n=12), and healthy control group (n=12) which matched with the VM group in gestational weeks. The amniotic fluid specimens were obtained during amniocentesis or cesarean section. The NGF levels in amniotic fluid were detected with en-zyme-linked immunosorbent assay. Results A significantly negative correlation was found between gestational age and the NGF level in amniotic fluid (r= 0.6149, P<0.0001). The NGF level in patients with fetal VM was significantly lower than that in healthy controls (33.95±29.24 pg/mL vs. 64.73±16.21 pg/mL, P=0.024). Conclusion NGF levels in amniotic fluid may be a sensitive marker for fetal VM.

Amniotic fluid embolism:literature review and an integrated concept of pathomechanism

Literature concerning procoagulant activity of the amniotic fluid and pathomechanism of amniotic fluid embolism (AFE) was surveyed and a new concept of its pathogenesis, called the integrated concept of AFE, was presented. According to this concept, two components of the amniotic fluid are involved: (i) apoptosis-affected amniotic cells showing a special role in the initiation of disseminated intravascular coagulation (DIC) and (ii) leukotrienes (formerly called slow-reacting substances), inducing bronchial and pulmonary vascular smooth muscle contraction. Although each of these components initiates a different pathogenic pathway, they both lead to the formation of a mechanical barrier on blood flow through the lungs (amniotic debris + microemboli) and/or functional barrier (pulmonary vasoconstriction). An old dilemma, concerning indications for heparin therapy in AFE was recalled in the light of the new concept.

Effects of amniotic fluid embolism-like plasma on isolated perfused rabbit lungs

<Abstract>Effects of amniotic fluid embolism-like plasma (AFEP) on the isolated perfused rabbit lungs (IPRL)were studied. It was found that AFEP could induce elevation of pulmonary artery pressure (PAP) and development of lung edema, which could be partially prevented by ibuprofen, a cycloxygenase inhibit0r, but amniotic fluid itself could not cause elevation of PAP and lung edema. The result suggests that AFEP-induced mediator from whole blood cells may be the important factor resulting in above-mentioned pathological changes.

A Novel Method for the Prenatal Diagnosis of Cleft Palate Based on Amniotic Fluid Metabolites

Background and purpose The prenatal diagnosis of cleft palate is an important component of sequential therapy,but the relevant diagnostic methods are still limited.We aimed here,to explore the possibility of an early prenatal diagnosis of cleft palate by assessing metabolites in pregnant mice.Methods Twenty-four inseminated females were randomly divided into retinoic acid(RA)-treated(treated with retinoic acid at 10.5 gestation days)and control groups.The metabolites of the embryonic palatal tissue,maternal amniotic fluid,and serum were characterized using 9.4T magnetic resonance spectroscopy in vitro.Then,a predictive model was established through the principal component analysis(PCA),and the correlations between the metabolites of amniotic fluid and palatal tissue were explored using orthogonal-2 partial least squares(O2-PLS).Results The incidences of cleft palate were 100%and 0%in the RA-treated and control groups,respectively.A predictive PCA model with a high specificity and sensitivity was established for the early prenatal diagnosis of isolated cleft palate using amniotic fluid metabolic data.Between RA-treated and control mice,we found that two metabolites in the amniotic fluid and palatal tissue were correlated.Creatinine showed the same trend in the palatal tissue and amniotic fluid,while choline showed opposite trends in the two tissues.However,the data for serum metabolites could not be used to establish a prediction model.Conclusion This study indicates that assessing the metabolites of amniotic fluid is a potential approach for the prenatal diagnosis of isolated cleft palate.

Relationship between leptin levels in maternal blood,amniotic fluid,arterial and venous cord blood and fetal growth

Objective:To study the relationship between leptin concentration and fetal growth.Methods: Levels of leptin in maternal serum, amniotic fluid, arterial and venouscord blood of 65 normal parturients (gestational age 37-42weeks) were measured by ra-dioimmunoassay (RIA) method. At the same time, maternal blood lipids were detected.Neonates were divided into three groups: small for gestational age (SGA) group (n=10), appropriate for gestational age (AGA) group (n=45), large for gestational age(LGA) group (n= 10). Statistical analysis was performed by t test, variance analysisand correlation analysis.Results: (1) There was no obvious correlation between leptin concentrations in ma-ternal serum and arterial/ venous cord blood, amniotic fluid, and also no correlationwith birth weight and placental weight (P＞0.05). Maternal body mass index signifi-cantly correlated with birth weight and neonatal length and leptin levels in arterial andvenous cord blood (P＜0.01). Leptin levels in arterial and venous cord blood positivelycorrelated significantly with placental and neonatal weight and body length (P＜0.01)and negatively correlated with high density lipoprotein (P＜0. 01). There was no obvi-ous correlation between fetal gender and leptin concentrations in maternal serum, arteri-al and venous cord blood and amniotic fluid; (2) Leptin levels in arterial and venouscord blood , placental weight in LGA group were significantly higher than those in SGAand AGA group (P＜0.05). Among three groups, leptin concentrations in maternalblood were significantly higher than those in arterial and venous cord blood (P＜0.05).Conclusions: (1)Fetal leptin is synthesized in uterus, born of itself and placenta.Leptin levels in arterial and venous cord blood are related to the intrauterine growthpattern. It might positively regulate birth weight and body fat content. (2)Either mater-nal or fetal leptin was not correlated with fetal gender. There is no gender difference infetal leptin concentrations.

Anticardiolipin Antibody Isotype Determination in Amniotic Fluid of Pregnant Patients with Systemic Lupus Erythematosus and/or Antiphospholipid Syndrome

Objective: To determine the levels and isotypes of aCl, as well as anti beta 2 glycoprotein 1 (antiβ2-GP1) antibodies in serum and amniotic fluid of pregnant patients with SLE and/or APLS, and healthy pregnant women serving as a control group. Material and Methods: We analyzed serum and amniotic fluid of pregnant patients with SLE and/or APLS, and of healthy pregnant women through ELISA. Results were compared using a Student’s T test. Results: 6 of 13 patients (46.1%), 5 with SLE and one with primary APLS had antiphospholipid antibodies in amniotic fluid. Two patients had IgG aCl and 4 patients had antiβ2-GP1 (one of them also showing IgM) in amniotic fluid. In serum, 4 patients (30%) had antiphospholipid antibodies present (one IgG aCl and three anti β2-GP1) as opposed to none in the control group having antiphospholipid antibodies in amniotic fluid. Only one control had IgM aCl in serum. Antiβ2-GP1 in the amniotic fluid of patients showed a statistically significant value when compared to controls. Conclusion: aCl and antiβ2-GP1 may be present in the amniotic fluid of patients with and without a history of fetal loss. The presence of IgM aCl and antiβ2-GP1 in amniotic fluid suggests its localized production.

Maternal and Fetal Outcomes Following Labour at Term in Singleton Pregnancies with Meconium-Stained Amniotic Fluid: A Prospective Cohort Study

Background: Meconium stained amniotic fluid (MSAF) is frequently encountered in obstetric practice. Literature on the subject is still poorly documented in the African setting. Objective: The aim of this study was to determine the maternal and fetal outcomes in case of meconium stained amniotic fluid observed during term labour. Materials and Methods: We conducted a prospective cohort study enrolling all consenting pregnant women with term singleton fetus in cephalic presentation admitted for labour with ruptured fetal membranes in the maternity units of the Yaoundé Central Hospital (YCH) and the Yaoundé Gynaeco-Obstetric and Pediatric Hospital (YGOPH) of Cameroon between December 2014 and April 2015. The exposed grouped was considered as participants having MSAF, while the non-exposed group comprised those with clear amniotic fluid (CAF). The two groups were monitored during labor using the WHO partograph, and then followed up till 72 hours after delivery. Variables studied included the colour and texture of amniotic fluid as well as maternal and fetal complications. Data was analyzed using Epi-info version 3.5.4. The chi-square and Fischer’s exact tests were appropriately used to compare the two groups. A p-value less than 5% was considered statistically significant. Results: 2376 vaginal deliveries were recorded during the study period among which MSAF was observed in 265 cases, hence a prevalence rate of MSAF of 11.15%. Among these cases of MSAF, 52.1% was thick meconium and 47.9% was light meconium. Maternal morbidity was high in the group with MSAF;these included: Higher proportions of caesarean delivery (RR = 2.35 p -4) and prolonged labor (RR = 3 p -4). In this same group, the incidences of chorioamnionitis and puerperal sepsis were low (0.94% and 0.70% respectively), although there was a three-fold higher risk that was not statistically significant (RR = 3, P = 0.31). Fetal and neonatal outcomes were poorer in the MSAF group compared to the CAF group. The complications included fetal heart rate abnormalities, low Apgar score at the 5th minute, need for neonatal resuscitation, neonatal asphyxia and neonatal infection which were significantly higher in the MSAF group (all p < 0.05). Meconium aspiration syndrome (MAS) was found in 2.34% of MSAF cases. Perinatal mortality was 2.34% and all cases of death occurred in the thick MSAF group. Conclusion: MSAF observed during labour is associated with increased perinatal morbidity and mortality. Its detection during labor should strongly indicate very rigorous intra partum and postpartum monitoring. This will ensure optimal management and reduction in the risks of complications.

Survival of a Patient with Amniotic Fluid Embolism Based on Multidisciplinary Team Training: A Case Report of a Swiss University Hospital

Amniotic fluid embolism (AFE) is a rare, unpredictable and unpreventable event with high maternal and fetal morbidity and mortality. Its clinical presentation is nonspecific ranging from moderate organ dysfunction to cardiovascular collapse with disseminated intravascular coagulation (DIC), which can lead to death. In a situation of severe systemic disease, maternal survival is largely dependent on the combined efficacy of gynecological and anesthetic teams. We report a case of AFE in a healthy woman admitted to the delivery room for labor induction. Due to a loss of consciousness soon after epidural anesthesia associated to fetal bradycardia, an emergency caesarean section was performed which was complicated by uterine atony and DIC requiring hysterectomy. The outcome was favorable due to fast and efficient multidisciplinary care, emphasizing the benefit of having been trained for such situations through simulation and team training programs for obstetrical emergency management.

Perinatal outcomes associated with meconium-stained amniotic fluid in Japanese singleton pregnancies

Introduction: We examined the perinatal outcomes in Japanese singleton pregnancies associated with meconium-stained amniotic fluid (MSAF) in relation to gestational age at delivery. Methods: We reviewed the obstetric records of all Japanese singleton deliveries after 22 weeks’ gestation managed at Japanese Red Cross Katsushika Maternity Hospital between 2002 and 2008 (n = 11,249). Results: The incidence of MSAF in the whole singleton pregnancies was 13%. The incidence of MSAF at preterm, term and post-term were 9.1%, 13% and 48%, respectively. The incidence of intrauterine fetal death, low Apgar score and low umbilical artery pH at delivery in cases with MSAF were significantly higher than those without MSAF in various gestational ages at delivery. Conclusion: Obstetric management should be affected by meconium in the amniotic fluid.

Identification of interleukin-6 (IL-6) and squamous cell carcinoma (SCC) as amniotic fluid-specific markers

Objective: To determine if an amniotic fluid (AF)-specific marker is present and if its concentration changes with the presence of labor. Study Design: Twenty-six healthy women who gave birth to healthy newborns at term during the period from July 2009 to January 2010 were included in the study. Six candidate markers were assessed by commercially available ELISA kits: interleukin (IL)-6, squamous cell carcinoma (SCC) antigen, insulin-like growth factor (IGFBP)-1, osteopontin (OPN), CA125, and sialyl Tn (STN). Results: The AF/maternal serum (MS) measurement based on IL-6 or SCC has proved to be superior to IGFBP-1, CA125, OPN and STN. Women with spontaneous labor at term had significantly higher IL-6 and IGFBP-1 concentrations in AF compared with those without labor. No significant differences were observed in the AF concentrations of SCC, OPN, CA125 and STN between women with labor and those not in labor. Conclusion: Our observation of IL-6 and SCC in AF may open a new area of research to assess their usefulness as biological markers of obstetrical disorders.