Histologic chorioamnionitis is associated with fetal growth restriction in term and preterm infants

Birth weight and head circumference discordance and outcome in preterms: results from the EPIPAGE-2 cohort

OBJECTIVE

To determine whether the relative measurement of birth weight (BW) and head circumference (HC) in preterm infants is associated with neurological outcomes.

METHODS

The EPIPAGE-2 Study included 3473 infants born before 32 weeks' gestation, classified based on their Z-score of BW and HC on the Fenton curves as concordant (≤1 SD apart) or discordant (>1 SD difference). We defined four mutually exclusive categories: discordant smaller BW (sBW) with BW-1SD and concordant small measurement (CsM) with BW and HC concordant and both ≤-1SD. Neurological outcomes at 5.5 years were evaluated with standard tests.

RESULTS

2592 (74.8%) preterm neonates were categorised as CM, 258 (7.4%) CsM, 378 (10.9%) sHC and 239 (6.9%) sBW. Compared with the CM children, those born with CsM had significantly higher risks of cognitive deficiency (adjusted OR (aOR) 1.3, 95% CI (1.0 to 2.0)), developmental coordination disorders (aOR 2.6 (1.5 to 4.4)) and need for special school services (aOR 2.3 (1.5 to 3.7)). Those born with sBW had significantly lower risk of cognitive deficiency (aOR 0.6 (0.4 to 0.9)) and the sHC group significantly higher risk of developmental coordination disorders (aOR 1.8 (1.0 to 3.2)).

CONCLUSIONS

The relative discordance of these preterm infants' BW and HC was associated with their neurological outcomes. It merits further exploration as an indirect indicator of development.

TRIAL REGISTRATION NUMBER

NCT03078439.

Association between Elevated Intrauterine Resting Tone during Labor and Neonatal Morbidity

OBJECTIVE

Internal contraction monitoring provides a quantitative assessment of intrauterine resting tone. During the course of labor, elevated intrauterine resting tone may be identified. We hypothesized that elevated intrauterine resting tone could lead to compression of the spiral arteries, thus limiting uterine blood flow and resulting in neonatal compromise. Therefore, our objective was to assess the association between elevated resting tone during labor and neonatal morbidity.

STUDY DESIGN

This was a secondary analysis of a prospective cohort study of singleton deliveries at ≥37 weeks of gestation. Patients with ruptured membranes and an intrauterine pressure catheter in place for at least 30 minutes prior to delivery were included. Intrauterine resting tone was calculated as the average baseline pressure between contractions during the 30 minutes prior to delivery. The study group had elevated intrauterine resting tone, defined as intrauterine resting tone ≥75th percentile (≥12.3 mm Hg). Primary outcome was composite neonatal morbidity: hypoxic-ischemic encephalopathy, hypothermia treatment, intubation, seizures, umbilical arterial pH ≤7.1, oxygen requirement, or death. Secondary outcomes included umbilical artery pH <7.2, lactate ≥4 mmol/L, and rates of neonatal intensive care unit admission.

RESULTS

Of the 8,580 patients in the cohort, 2,210 (25.8%) met the inclusion criteria. The median intrauterine resting tone was 9.7 mm Hg (interquartile range: 7.3-12.3 mm Hg). Elevated resting tone was associated with a shorter median duration of the first stage of labor (10.0 vs. 11.0 hours, p < 0.01) and lower rates of labor induction and oxytocin augmentation (p < 0.01). Neonatal composite morbidity was higher among patients with elevated intrauterine resting tone (5.1 vs. 2.9%, p = 0.01). After adjusting for chorioamnionitis and amnioinfusion, elevated intrauterine resting tone was associated with increased risk of neonatal morbidity (adjusted odds ratio: 1.70, 95% confidence interval: 1.06-2.74).

CONCLUSION

Our findings suggest that elevated intrauterine resting tone is associated with increased risk of neonatal composite morbidity.

KEY POINTS

· Higher intrauterine resting tone is associated with increased risk of neonatal morbidity.. · Elevated intrauterine tone can negatively impact umbilical artery pH and lactate levels.. · If elevated intrauterine pressure is noted, we recommend close monitoring of fetal status..

Ambient air pollution and adverse birth outcomes: A review of underlying mechanisms

Epidemiological data provide varying degrees of evidence for associations between prenatal exposure to ambient air pollutants and adverse birth outcomes (suboptimal measures of fetal growth, preterm birth and stillbirth). To assess further certainty of effects, this review examines the experimental literature base to identify mechanisms by which air pollution (particulate matter, nitrogen dioxide and ozone) could cause adverse effects on the developing fetus. It likely that this environmental insult impacts multiple biological pathways important for sustaining a healthy pregnancy, depending upon the composition of the pollutant mixture and the exposure window owing to changes in physiologic maturity of the placenta, its circulations and the fetus as pregnancy ensues. The current body of evidence indicates that the placenta is a target tissue, impacted by a variety of critical processes including nitrosative/oxidative stress, inflammation, endocrine disruption, epigenetic changes, as well as vascular dysregulation of the maternal-fetal unit. All of the above can disturb placental function and, as a consequence, could contribute to compromised fetal growth as well increasing the risk of stillbirth. Furthermore, given that there is often an increased inflammatory response associated with preterm labour, inflammation is a plausible mechanism mediating the effects of air pollution on premature delivery. In the light of increased urbanisation and an ever-changing climate, both of which increase ambient air pollution and negatively affect vulnerable populations such as pregnant individuals, it is hoped that the collective evidence may contribute to decisions taken to strengthen air quality policies, reductions in exposure to air pollution and subsequent improvements in the health of those not yet born.

Blockade of IL-6R prevents preterm birth and adverse neonatal outcomes

BACKGROUND

Preterm birth preceded by spontaneous preterm labour often occurs in the clinical setting of sterile intra-amniotic inflammation (SIAI), a condition that currently lacks treatment.

METHODS

Proteomic and scRNA-seq human data were analysed to evaluate the role of IL-6 and IL-1α in SIAI. A C57BL/6 murine model of SIAI-induced preterm birth was developed by the ultrasound-guided intra-amniotic injection of IL-1α. The blockade of IL-6R by using an aIL-6R was tested as prenatal treatment for preterm birth and adverse neonatal outcomes. QUEST-MRI evaluated brain oxidative stress in utero. Targeted transcriptomic profiling assessed maternal, foetal, and neonatal inflammation. Neonatal biometrics and neurodevelopment were tested. The neonatal gut immune-microbiome was evaluated using metagenomic sequencing and immunophenotyping.

FINDINGS

IL-6 plays a critical role in the human intra-amniotic inflammatory response, which is associated with elevated concentrations of the alarmin IL-1α. Intra-amniotic injection of IL-1α resembles SIAI, inducing preterm birth (7% vs. 50%, p = 0.03, Fisher's exact test) and neonatal mortality (18% vs. 56%, p = 0.02, Mann-Whitney U-test). QUEST-MRI revealed no foetal brain oxidative stress upon in utero IL-1α exposure (p > 0.05, mixed linear model). Prenatal treatment with aIL-6R abrogated IL-1α-induced preterm birth (50% vs. 7%, p = 0.03, Fisher's exact test) by dampening inflammatory processes associated with the common pathway of labour. Importantly, aIL-6R reduces neonatal mortality (56% vs. 22%, p = 0.03, Mann-Whitney U-test) by crossing from the mother to the amniotic cavity, dampening foetal organ inflammation and improving growth. Beneficial effects of prenatal IL-6R blockade carried over to neonatal life, improving survival, growth, neurodevelopment, and gut immune homeostasis.

INTERPRETATION

IL-6R blockade can serve as a strategy to treat SIAI, preventing preterm birth and adverse neonatal outcomes.

FUNDING

NICHD/NIH/DHHS, Contract HHSN275201300006C. WSU Perinatal Initiative in Maternal, Perinatal and Child Health.

The risk factors of preterm birth: A multicentre case-control survey in China in 2018

OBJECTIVES

To investigate the risk profile of preterm birth (PTB) in 2018 in China.

METHOD

A prospective multicentre case-control study was conducted in 15 hospitals located in seven provinces throughout three geographical areas (the Eastern, South-Central and North-Western regions) in China. A total of 3147 preterm (<37⁺⁰ weeks) and 3147 term (37⁺⁰ to 41⁺⁶ weeks) live-birth mothers were included. Designed questionnaires were used to investigate maternal and fetal information. We calculated multivariable logistic regression and population attributable risk (PAR).

RESULTS

Iatrogenic PTB accounted for 48.1% of preterm mothers. Multivariable analysis showed PTB was significantly associated with six categories of maternal and fetal factors, adverse life-style and psychological conditions (adjusted odds ratio (aOR) 2.063, 95% confidence interval (CI) 1.601-2.657) had the highest PAR% (60.1%). High school and below education level (PAR% = 25.8%), living in town or village (PAR% = 24.4%), low pregnant weight gain (PAR% = 16.8%), hypertensive disorders in pregnancy (aOR: 5.010, 95% CI: 4.039-6.216, PAR% = 15.3%), placental abnormality (aOR: 4.242, 95% CI: 3.454-5.211, PAR% = 14.1%) and multiple pregnancy (aOR: 10.990, 95% CI: 7.743-15.599, PAR% = 11.8%) were significantly associated with PTB with high PAR% value.

CONCLUSION

The main risk factors for PTB in China were placental abnormality, hypertensive disorders in pregnancy and multiple pregnancy. Adverse life-style and psychological conditions and socio-economic disadvantage had high public health significance.

Placental findings in singleton stillbirths: a case-control study from a tertiary-care center in India

OBJECTIVES

Placental examination in a case of stillbirth can provide insight into causative/associated factors with fetal demise. The aim of this study was to compare placental and umbilical cord pathologies in singleton stillbirth and livebirth placentas, and to find prevalence of various associated maternal and fetal clinical factors.

METHODS

This case-control study was conducted at a tertiary-care center in India over a period of 20 months. About 250 women who delivered stillborn fetus ≥28 weeks' gestation and 250 maternal-age-matched controls were recruited. Sociodemographic and clinical details were noted and placental gross and microscopic examination was done. Placental findings were compared between stillbirth and livebirth (overall), preterm stillbirth and preterm livebirth as well as term stillbirth and term livebirth in six categories - placenta gross, cord gross, membranes gross, maternal vascular malperfusion, fetal vascular malperfusion and inflammatory response. Prevalence of 11 maternal and fetal factors were studied in all categories of placental findings in both livebirth and stillbirth.

RESULTS

Placental findings in all six categories were significantly associated with stillbirths (p<0.05). The placental findings associated with stillbirth with highest odds included placental hypoplasia (OR 9.77, 95% CI 5.46-17.46), necrotizing chorioamnionitis (OR 9.30, 95% CI 1.17-73.96) and avascular villi (OR 8.45, 95% CI 3.53-20.25). More than half of the women with stillbirths had medical disorders (n=130, 52.0%) and the most prevalent was hypertensive disorder (n=45, 18.0%).

CONCLUSIONS

Changes in placenta are associated with development of stillbirth. Therefore, antenatal investigations to identify placental dysfunction should be investigated to determine whether these reduce stillbirth. Also, placental examination in a case of stillbirth can detect/diagnose many maternal/fetal conditions and thereby can help in preventing future stillbirths.

Acute Histological Chorioamnionitis and Birth Weight in Pregnancies With Preterm Prelabor Rupture of Membranes: A Retrospective Cohort Study

Aim: To assess the association between the birth weight of newborns from pregnancies with preterm prelabor rupture of membranes (PPROM) and the presence of acute histological chorioamnionitis (HCA) with respect to the: i) fetal and maternal inflammatory responses and ii) acute inflammation of the amnion.

Material and Methods: This retrospective cohort study included 818 women with PPROM. A histopathological examination of the placenta was performed. Fetal inflammatory response was defined as the presence of any neutrophils in umbilical cord (histological grades 1–4) and/or chorionic vasculitis (histological grade 4 for the chorionic plate). Maternal inflammatory response was defined as the presence of histological grade 3–4 for the chorion-decidua and/or grade 3 for the chorionic plate and/or grade 1–4 for the amnion. Acute inflammation of the amnion was defined as the presence of any neutrophils in the amnion (histological grade 1–4 for the amnion). Birth weights of newborns were expressed as percentiles derived from INTERGROWTH-21st standards for the i) estimated fetal weight and ii) newborn birth weight.

Results: No difference in percentiles of birth weights of newborns was found among the women with the women with HCA with fetal inflammatory response, with HCA with maternal inflammatory response and those without HCA. Women with HCA with acute inflammation of the amnion had lower percentiles of birth weights of newborns, derived from the estimated fetal weight standards, than women with HCA without acute inflammation of the amnion and those with the absence of HCA in the crude (with acute inflammation: median 46, without acute inflammation: median 52, the absence of HCA: median 55; p = 0.004) and adjusted (p = 0.02) analyses. The same subset of pregnancies exhibited the highest rate of newborns with a birth weight of ≤25 percentile. When percentiles were derived from the newborn weight standards, no differences in birth weights were observed among the subgroups.

Conclusion: Acute inflammation of the amnion was associated with a lower birth weight in PPROM pregnancies, expressed as percentiles derived from the estimated fetal weight standards.

Role of JNK, ERK, and p38 MAPK signaling pathway in protective effect of sildenafil in cyclophosphamide-induced placental injury in rats

AIMS

Chemotherapeutic agents; cyclophosphamide (CYC) is used for treatment of cancer and autoimmune diseases. Grievously, CYC is non-selective as it affects both tumor and healthy cells resulting in systemic toxicity including placenta. The present study aimed to evaluate the effect of phosphodiesterase 5 inhibitor, sildenafil (Sild) on CYC-induced placental injury in rats.

MATERIALS AND METHODS

Thirty-two female Wister rats were randomly divided into 4 experimental groups. Group 1: control pregnant group; Group 2: Sild-treated pregnant rats; Group 3: pregnant rats received CYC; Group 4: pregnant rats received Sild and CYC. Placental malondialdehyde (MDA), total nitrite/nitrate (NOx), reduced glutathione (GSH), tumor necrosis factor-α (TNF-α), platelet growth factor (PlGF), c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38MAPK), extracellular signal-regulated kinase (ERK) and cleaved caspase-3 were measured. Histological changes, Nuclear Factor kappa-light-chain-enhancer of activated B (NF-κB), Connexin 43 (GJA1) and proliferating cell nuclear antigen (PCNA) immuno-expressions were also evaluated.

KEY FINDINGS

CYC showed significant decrease in placental GSH, NOx, PlGF, GJA1 and PCNA immuno-expressions but significant increase in placental MDA, TNF-α, JNK, P38MAPK, ERK, caspase-3 and NF-kB immuno-expression. Sild showed significant improvement in all oxidative, inflammatory and apoptotic parameters.

SIGNIFICANCE

Sild is a promising protective drug against placental injury induced by CYC through antagonizing MAPK (JNK, ERK, and p38) signaling pathway with anti-oxidant, anti-inflammatory and anti-apoptotic effects.

Birth weight and intra-amniotic inflammatory and infection-related complications in pregnancies with preterm prelabor rupture of membranes: a retrospective cohort study

OBJECTIVE

To assess the association between the birth weight of newborns and microbial invasion of the amniotic cavity (MIAC) and/or intra-amniotic inflammation in pregnancies with preterm prelabor rupture of membranes.

METHODS

A total of 528 pregnancies with preterm prelabor rupture of membranes were included in this retrospective cohort study. Transabdominal amniocentesis to determine the presence of MIAC (through culturing and molecular biology methods) and intra-amniotic inflammation (according to amniotic fluid interleukin-6 level) was performed as part of standard clinical management. Based on the presence of MIAC and/or intra-amniotic inflammation, the participants were divided into four subgroups: with intra-amniotic infection (presence of both), with sterile IAI (intra-amniotic inflammation alone), with colonization (MIAC alone), and with negative amniotic fluid (absence of both). Birth weights of newborns are expressed as percentiles derived from INTERGROWTH-21st standards for (i) newborn birth weight and (ii) estimated fetal weight.

RESULTS

No differences in birth weights, expressed as percentiles derived from newborn weight standards (infection: median 52; sterile: median 54; colonization: median 50; negative amniotic fluid: median 51; p = .93) and estimated fetal weight standards (infection: median 47; sterile: median 51; colonization: median 47; negative amniotic fluid: median 53; p = .48) were found among the four subgroups. No differences in percentiles (derived from both standards) were found in the subset of participants who delivered within 72 h after rupture of membranes (newborn weight standard, p = .99; estimated fetal weight standard, p = .81).

CONCLUSIONS

No association was identified between the birth weight of newborns and the presence of intra-amniotic inflammatory and infection-related complications in pregnancies with preterm prelabor rupture of membranes.

Intra-Amniotic Infection and Sterile Intra-Amniotic Inflammation in Cervical Insufficiency with Prolapsed Fetal Membranes: Clinical Implications

INTRODUCTION

The aim of this study was to identify the rates of 2 phenotypes of intra-amniotic inflammation: intra-amniotic infection (with microbial invasion of the amniotic cavity [MIAC]) and sterile intra-amniotic inflammation (without MIAC), and their outcomes, among women with cervical insufficiency with prolapsed fetal membranes.

METHODS OF STUDY

This is a retrospective study of women admitted to the Department of Obstetrics and Gynecology, University Hospital Hradec Kralove between January 2014 and May 2020. Transabdominal amniocentesis to evaluate intra-amniotic inflammation (amniotic fluid interleukin-6) and MIAC (culturing and molecular biology methods) was performed as part of standard clinical management.

RESULTS

In total, 37 women with cervical insufficiency and prolapsed fetal membranes were included; 11% (4/37) and 43% (16/37) of them had intra-amniotic infection and sterile intra-amniotic inflammation, respectively. In women with intra-amniotic infection and sterile intra-amniotic inflammation, we noted shorter intervals between admission and delivery (both p < 0.0001), and lower gestational age at delivery (p < 0.0001 and p = 0.004) and percentiles of birth/abortion weight (p = 0.03 and p = 0.009, respectively) than in those without intra-amniotic inflammation.

CONCLUSIONS

Both phenotypes of intra-amniotic inflammation, with sterile intra-amniotic inflammation being more frequent, are associated with worse outcomes in pregnancies with cervical insufficiency with prolapsed fetal membranes.

The effect of concomitant histologic chorioamnionitis in pregnancies complicated by fetal growth restriction

INTRODUCTION

We aimed to investigate the effect of placental histologic chorioamnionitis (HC) on neonatal outcomes in pregnancies complicated by fetal growth restriction (FGR).

METHODS

- The computerized medical files of all pregnancies diagnosed with FGR (birthweight <10th percentile) at 24-42 weeks of gestation between 2008 and 2019 were reviewed. Maternal and neonatal outcomes were compared between FGR with and without evidence of placental HC. Placental lesions were classified according to "Amsterdam" criteria. Composite adverse neonatal outcome-included any of the following complications: neurological morbidity, neonatal respiratory assistance, RDS, NEC, sepsis, blood transfusion, phototherapy, hypoglycemia, or neonatal death. Composite severe adverse neonatal outcome included any of the following complications - neurological morbidity, blood transfusion, NEC, sepsis, RDS, neonatal death.

RESULTS

- Compared to FGR without HC (n = 446), FGR with HC (n = 57) was characterized by more advanced gestational age at delivery 39.2 (38.3-39.9) vs. 38.2 (36.9-39.2), weeks respectively, p < 0.001), higher rate of nulliparity (73.7% vs. 45.1%, p < 0.001), less vascular lesions of MVM (1.8% vs.11.2%, p = 0.02), higher rate of Apgar scores at 5 min <7 (10.5% vs. 2%, p = 0.004), increased neonatal death (7.0% vs. 0.9%, p = 0.007), higher rates of both composite adverse neonatal outcome (31.1% vs. 17.3% p = 0.02), and composite severe adverse neonatal outcome (16.3% vs. 8.2% p = 0.04). By multivariate regression analysis HC was found to be independently associated with composite adverse neonatal outcome (aOR = 1.21, 95% CI 1.08-2.38) and with severe composite adverse neonatal outcome (aOR = 1.39, 95% CI 1.16-3.76).

CONCLUSIONS

Pregnancies complicated by FGR with concomitant HC were associated with higher rates of adverse neonatal outcomes.

Intrauterine bacterial growth in elective and non-elective caesarean sections

We assessed intrauterine bacterial growth for elective and non-elective caesarean sections (CSs). Aerobic uterine cultures were obtained from the uterine cavity immediately following placental removal from 1376 patients who underwent CS in one center during one year. About 13.8% (115/832) of elective CS were positive vs. 55.9% (304/544) of non-elective CS (p < .001). Of non-elective CSs, 28.6% (56/196) of those without ruptured membranes (ROM) were positive vs. 71.3% (248/348) with ROM (p < .001). Mean birth weight and 1-minute Apgar scores were significantly lower in women with positive cultures, elective and non-elective, than negative cultures. A higher percentage of women with positive uterine cultures presented with postpartum endometritis (p < .05). Intrauterine bacteria in elective CSs demonstrate that the uterine cavity is not sterile. Non-elective CS, particularly after membrane rupture, is a significant risk factor for positive uterine culture. Positive uterine culture is associated with lower birth weight, lower one-minute Apgar score and postpartum endometritis.Impact statementWhat is already known on this subject? Postpartum endometritis is a leading cause of postpartum febrile morbidity. Caesarean sections, in particular non-elective cesareans, are an important risk factor for the development of postpartum endometritis. Controversy exists concerning the sterility of the placenta and uterus. The diagnosis of endometritis is based mainly on clinical findings and does not necessitate bacterial isolation from the uterine cavity. Positive culture at caesarean section has been associated with positive postoperative culture and yet, currently, professional organisations do not recommend the routine sampling of intrauterine cultures during caesarean section.What do the results of this study add? Since positive uterine culture rate was higher in non-elective CSs and associated with lower birth weight and 1-minute Apgar score and postoperative endometritis, obtaining uterine culture in those cases might be of clinical value.What are the implications of these findings for clinical practice and/or further research? Obtaining routine intrauterine cultures during non-elective caesarean sections might be useful for detecting significant pathogens and tailoring antibiotic treatment in postpartum endometritis. Further studies are necessary in order to determine the impact of obtaining intrauterine cultures during caesarean sections, particularly non-elective cesareans.

A comparison of placental pathology between small for gestational age infants at < 5 % versus 5-9

INTRODUCTION

Among SGA newborns, those < 5th % for GA are more likely to have adverse outcomes than those at 5-9th %. The differential morbidity and mortality may be due to abnormal placental pathology between groups. Our purpose was to compare placental pathology characteristics and composite placental pathology among SGA infants with birth weights <5th % vs. 5-9th %.

METHODS

This study is a secondary analysis of a multicenter, retrospective cohort study. Placental pathological variables and composite placental pathology (CPP) among SGA infants <5th % and 5-9th % were compared. Multivariable logistic regression was used to model the probability of an infant's birth weight being classified as <5th % based on pathology characteristics.

RESULTS

Of 11,487 live singleton births, 925 SGA infants met inclusion criteria. Placental pathology was available for review in 407 (44 %) SGA infants: 210 (51.6 %) <5th % and 197 (48.4 %) 5-9th %. A decreased placental weight for GA, was more common in the <5th % group compared to the 5-9th % group (p = 0.0019). No significant differences in the distribution of pathological variables or in CPP (p = 0.3) was observed between the two centile groups. A decreased placental weight was the only reliable predictor of an infant's birth weight centile group (p = 0.0018).

CONCLUSIONS

Placental hypoplasia, reflected by a decreased placental weight for GA, was significantly more common among SGA infants < 5th % compared to the 5-9th %. There was no difference in placental pathological features or CPP between the two centile groups of SGA infants.

Impact of histological chorioamnionitis on postnatal growth in very-low birth weight infants

BACKGROUND

Postnatal growth restriction remains one of the most common problems of very preterm infants (VPI). Chorioamnionitis is a frequent cause of prematurity. Both have been related to worse postnatal outcomes.

OBJECTIVES

To evaluate the influence of histological chorioamnionitis (CA) on postnatal growth in very premature infants.

METHODS

Retrospective one-to-one matched cohort study assessing growth in infants born at or below 32.0 weeks gestation from mothers for whom histological examination of the placenta was available. Newborns with histological CA were matched and compared with those without it. Postnatal growth was recorded at admission, 14 days of life, 28 days of life and 36 weeks postmenstrual age (PMA). Nutritional support and clinical outcomes were used as covariables.

RESULTS

Eighty-eight patients were included: 44 with fetal or/and maternal placental inflammation, and 44 without histological CA (41% with vasculopathy findings and 59% without). Baseline characteristics were similar between the groups. Change in weight z-scores at 14 days of life, 28 days of life, 36 weeks PMA or at discharge were similar in both groups, with a steady fall and no signs of catch-up. No differences were found in enteral and parenteral nutritional intakes between groups.

CONCLUSIONS

Histological CA did not affect postnatal growth of very preterm infants after matching for birth weight z-scores with non-CA newborns.

Postnatal inflammation following intrauterine inflammation exacerbates the development of atherosclerosis in ApoE−/− mice

Atherosclerosis is a chronic inflammatory disease that has its origins in early life. Postnatal inflammation exacerbates atherosclerosis, but the possible effect of intrauterine inflammation is largely unexplored. Exposure to inflammation in utero is common, especially in infants born preterm, who have increased cardiovascular risk in adulthood. We hypothesised that exposure to inflammation before birth would accelerate the development of atherosclerosis, with the most severe atherosclerosis following exposure to both pre- and postnatal inflammation. Here we studied the effect of prenatal and postnatal inflammation on the development of atherosclerosis by combining established techniques for modelling histological chorioamnionitis and atherosclerosis using apolipoprotein E (ApoE) knockout mice. A single intra-amniotic (IA) injection of lipopolysaccharide (LPS) caused intrauterine inflammation, and increased atherosclerosis at 13 weeks of postnatal age. In mice exposed to postnatal LPS, chorioamnionitis modulated subsequent responses; atherosclerotic lesion size, number and severity were greatest for mice exposed to both intrauterine and postnatal inflammation, with a concomitant decrease in collagen content and increased inflammation of the atherosclerotic plaque. In conclusion, pre- and postnatal inflammation have additive and deleterious effects on the development of atherosclerosis in ApoE knockout mice. The findings are particularly relevant to preterm human infants, whose gestations are frequently complicated by chorioamnionitis and who are particularly susceptible to repeated postnatal infections. Human and mechanistic studies are warranted to guide preventative strategies.

Histological chorioamnionitis at term according to labor onset: a prospective controlled study

OBJECTIVE

To study the incidence of histological chorioamnionitis (HCA) in term pregnancies according to labor onset.

STUDY DESIGN

During 2013-6, term pregnancy placentas were prospectively sent to histopathology evaluation, and compared between patients with spontaneous onset labor, pre-labor ROM, labor induction and elective cesarean deliveries.

RESULTS

A total of 260 placentas were obtained, 65 from each group. Rates of HCA for the spontaneous labor, PROM, induction and CD groups were: 49, 32, 24 and 4%, respectively (p < 0.001). Composite neonatal outcome was non-significant between the study groups, and between cases with and without HCA. In a logistic regression model, after controlling for parity - gestational age, mode of delivery, ROM > 12 h and spontaneous onset of labor were found to be independent risk factors for HCA.

CONCLUSION

HCA at term is prevalent in spontaneous labor and supports the association between the inflammatory processes and activation of the physiological signals of parturition.

Placental pathology predicts infantile physical development during first 18 months in Japanese population: Hamamatsu birth cohort for mothers and children (HBC Study)

The present study aimed to investigate the relationship between placental pathological findings and physiological development during the neonate and infantile periods. Study participants were 258 infants from singleton pregnancies enrolled in the Hamamatsu Birth Cohort for Mothers and Children (HBC Study) whose placentas were stored in our pathological division. They were followed up from birth to 18 months of age. Physiological development (body weight and the ponderal index [PI]) was assessed at 0, 1, 4, 6, 10, 14, and 18 months. Placental blocks were prepared by random sampling and eleven pathological findings were assessed, as follows: 'Accelerated villous maturation', 'Decidual vasculopathy', 'Thrombosis or Intramural fibrin deposition', 'Avascular villi', 'Delayed villous maturation', 'Maternal inflammatory response', 'Fetal inflammatory response', 'Villitis of unknown etiology (VUE)', 'Deciduitis', 'Maternal vascular malperfusion', and 'Fetal vascular malperfusion'. Mixed model analysis with the use of the xtmixed command by the generic statistical software, Stata version 13.1., identified 'Accelerated villous maturation' and 'Maternal vascular malperfusion' as significant predictors of a lower body weight and 'Deciduitis' as a significant predictor of a small PI, throughout the first 18 months of life. In conclusion, the present study is the first to demonstrate that some pathological findings of the placenta are associated with changes in infantile physical development during the initial 18 months of life in the Japanese population.

Impact of histologic chorioamnionitis on pulmonary hypertension and respiratory outcomes in preterm infants

We aimed to evaluate the association between the presence of histologic chorioamnionitis (HC) and development of pulmonary hypertension (PH) during neonatal intensive care unit (NICU) stay. Data of preterm infants born at 32 weeks of gestation or less were reviewed. The development of PH and other respiratory outcomes were compared according to the presence of HC. Potential risk factors associated with the development of PH during NICU stay were used for multivariable logistic regression analysis. A total of 188 infants were enrolled: 72 in the HC group and 116 in the no HC group. The HC group infants were born at a significantly shorter gestational age and lower birthweight, with a greater proportion presenting preterm premature rupture of membrane (pPROM) > 18 h before delivery. More infants in the HC group developed pneumothorax (P = 0.008), and moderate and severe bronchopulmonary dysplasia (BPD; P = 0.001 and P = 0.006, respectively). PH in the HC group was significantly more frequent compared to the no HC group (25.0% versus 8.6%, P = 0.002). Based on a multivariable logistic regression analysis, birthweight (P = 0.009, odds ratio [OR] = 0.997, 95% confidence interval [CI] = 0.995–0.999), the presence of HC (P = 0.047, OR = 2.799, 95% CI = 1.014–7.731), and duration of invasive mechanical ventilation (MV) > 14 days (P = 0.015, OR = 8.036, 95% CI = 1.051–43.030) were significant factors. The presence of HC and prolonged invasive MV in infants with lower birthweight possibly synergistically act against preterm pulmonary outcomes and leads to the development of PH. Verification of this result and further investigation to establish effective strategies to prevent or ameliorate these adverse outcomes are needed.

Effect of Fine Particulate Matter (PM2.5) on Rat Placenta Pathology and Perinatal Outcomes

Background

Fine particulate matter with aerodynamic diameters smaller than 2.5 μm (PM_2.5) has been reported to cause adverse effects on human health. Evidence has shown the association between PM_2.5 exposure and adverse perinatal outcomes, and the most common method is epidemiological investigation. We wished to investigate the impact of PM_2.5 on placenta and prenatal outcomes and its related mechanisms in a rat model.

Material/Methods

Pregnant rats were exposed to a low PM_2.5 dose (15 mg/kg) with intratracheal instillation at pregnant day 10 and day 18, while the controls received an equivalent volume normal saline. All rats received cesarean section 24 h after the last intratracheal instillation and were sacrificed with anesthesia. Blood routine tests (BRT) and interleukin-6 (IL-6) were detected for analyzing inflammation and blood coagulation. Placenta tissue sections underwent pathologic examination, and the levels of homogenate glutathione peroxidase (GSH-Px) and methane dicarboxylic aldehyde (MDA) were determined for oxidative stress estimation.

Results

Increased absorbed blastocysts, and lower maternal weight gain and fetal weight were found in the PM_2.5 exposure group compared to controls (p<0.05). Exposure to PM_2.5 caused a significant increase of blood mononuclear cells (PBMC), platelets, and IL-6 levels (P<0.01). There were no differences in GSH-Px and MDA of placenta homogenate between the 2 groups (P>0.05). Placenta pathological examination demonstrated thrombus and chorioamnionitis in the PM_2.5 exposure group.

Conclusions

PM_2.5 exposure can result in placental pathological changes and adverse perinatal outcomes. The placental inflammation and hypercoagulability with vascular thrombosis may play important roles in placental impairment, but oxidative stress appears to be less important.

Umbilical cord prostaglandins in term and preterm parturition

OBJECTIVE

Prostaglandins (PGs) are considered the universal mediators of parturition. Amniotic fluid PGE2 and PGF2α concentrations increase before the onset of spontaneous labor at term, as well as during labor. This study was conducted to determine if the concentrations of umbilical cord PGE2 and PGF2α change with advancing gestational age, spontaneous labor at term, and preterm labor (with and without funisitis).

METHODS

Umbilical cord (UC) tissue samples were obtained from women (N = 158) with singleton pregnancies in the following groups: (1) term deliveries without labor (TNL; n = 20); (2) term deliveries with labor (TIL; n = 20); (3) spontaneous preterm deliveries (sPTD) with (n = 20) and without acute funisitis (n = 20); and (4) preeclampsia without labor (n = 78). The concentrations of PGs were determined in different locations of the UC. PGE2 and PGF2α were measured by specific immunoassays. Non-parametric statistics were used for analysis.

RESULTS

(1) In spontaneous preterm deliveries, the median UC PGE2 concentration was higher in cases with funisitis than in those without funisitis (233.7 pg/µg versus 87.4 pg/µg of total protein, p = 0.001); (2) the median UC PGE2 concentration in sPTD with funisitis was also higher than that obtained from samples who had undergone labor at term (233.7 pg/µg versus 116.1 pg/µg of total protein, p = 0.03); (3) the UC PGE2 and PGF2α concentration increased as a function of advancing gestational age before 36 weeks (PGE2: ρ = 0.59, p < 0.001; PGF2α: ρ = 0.39, p = 0.01), but not after 36 weeks (PGE2: ρ = -0.1, p = 0.5; PGF2α: ρ = -0.2, p = 0.2); (4) the median UC concentrations of PGE2 and PGF2α at term was similar in samples obtained from women with and without labor (PGE2: TNL 133.7 pg/µg versus TIL 116.1 pg/µg of total protein, p = 0.9; PGF2α: TNL 8.4 pg/µg versus TIL 8.1 pg/µg of total protein, p = 0.7); and (5) there was no correlation between UC PG concentration and gestational age at term pregnancy (PGE2: ρ = 0.01, p = 0.9; PGF2α: ρ = 0.07, p = 0.7).

CONCLUSIONS

(1) PGE2 concentrations in the UC are higher in the presence of acute funisitis than in the absence of this lesion; (2) spontaneous labor at term was not associated with a change in the UC concentration of PGE2 and PGF2α; and (3) the UC concentrations of PGE2 and PGF2α increased as a function of gestational age. We propose that UC PGs act as inflammatory mediators generated in the context of fetal systemic inflammation.

A point of care test for interleukin-6 in amniotic fluid in preterm prelabor rupture of membranes: a step toward the early treatment of acute intra-amniotic inflammation/infection

OBJECTIVE

Preterm prelabor rupture of membranes (preterm PROM) accounts for 30-40% of spontaneous preterm deliveries and thus is a major contributor to perinatal morbidity and mortality. An amniotic fluid (AF) interleukin-6 (IL-6) concentration is a key cytokine for the identification of intra-amniotic inflammation, patients at risk of impending preterm delivery and adverse pregnancy complications. The conventional method to determine IL-6 concentrations in AF is an enzyme-linked immunosorbent assay (ELISA). However, this technique is not available in clinical settings, and the results may take several days. A lateral flow-based immunoassay, or point of care (POC) test, has been developed to address this issue. The objective of this study was to compare the performance of AF IL-6 determined by the POC test to that determined by ELISA for the identification of intra-amniotic inflammation in patients with preterm PROM.

MATERIALS AND METHODS

This retrospective cohort study includes 56 women with singleton pregnancies who presented with preterm PROM. Amniocentesis was performed at the time of diagnosis, and AF was analyzed using cultivation techniques for aerobic and anaerobic bacteria as well as genital mycoplasmas. AF Gram stain and AF white blood cell counts were determined. AF IL-6 concentrations were measured using both lateral flow-based immunoassay and ELISA. The primary outcome was intra-amniotic inflammation defined as AF ELISA IL-6 ≥ 2600 pg/ml. A previously determined cut-off of 745 pg/ml was used to define a positive POC test.

RESULTS

(1) The POC test for AF IL-6 concentrations had 97% sensitivity and 96% specificity for the identification of intra-amniotic inflammation, as defined using ELISA among patients with preterm PROM and (2) the diagnostic performance of the POC test for IL-6 was strongly correlated to that of an ELISA test for the identification of intra-amniotic inflammation and was equivalent for the identification of acute inflammatory placental lesions and microbial invasion of the amniotic cavity (MIAC).

CONCLUSION

A POC AF IL-6 test can identify intra-amniotic inflammation in patients with preterm PROM. Results can be available within 20 min - this makes it possible to implement interventions designed to treat intra-amniotic inflammation and improve pregnancy outcomes.

Term histologic chorioamnionitis: a heterogeneous condition

A histologic response of histologic chorioamnionitis (HCA) is defined as an intrauterine inflammatory condition characterized by acute granulocyte infiltration into the fetal-maternal or the fetal tissues. Prevalence of HCA is inversely correlated with gestational age, occurring in 50% of preterm birth and in up to 20% of deliveries at term. Regardless of these standard definitions, understanding HCA is challenging as it reflects a heterogeneous condition. A histologic response of HCA from term placentas often does not correspond to a clinical presentation; in this context, the present review aims to analyze main characteristics of this condition, in particular focusing on mechanisms and birth outcomes.

The relationship between the intensity of intra-amniotic inflammation and the presence and severity of acute histologic chorioamnionitis in preterm gestation

OBJECTIVE

Acute histologic chorioamnionitis (HCA) is associated with an increased risk of perinatal mortality and morbidity. The purpose of this study was to determine the relationship between the intensity of intra-amniotic inflammation (IAI) and the severity of acute HCA in preterm gestation.

METHODS

The relationship between the intensity of IAI and the presence and severity of acute HCA was examined in 412 patients with singleton gestations who delivered within 120 h of transabdominal amniocentesis. The concentration of amniotic fluid (AF) matrix metalloproteinase (MMP)-8 was assayed to determine the presence and intensity of IAI. Acute HCA was defined as the presence of inflammatory change in any tissue samples according to the criteria previously reported. The total grade of acute HCA was used to determine the severity of HCA.

RESULTS

(1) Patients with IAI had a significantly higher rate of acute HCA than those without IAI [76.9% (133/173)] versus 20.9% (50/239), p < 0.001]. The AF MMP-8 concentration was significantly higher in patients with acute HCA than in those without acute HCA (median [range]; 188.3 ng/ml [0.3-6142.6] versus 1.8 ng/ml [0.3-2845.5], p < 0.001); (2) Of 183 patients with acute HCA, the AF MMP-8 concentration was positively correlated with the severity of acute HCA (p < 0.001).

CONCLUSIONS

AF MMP-8 concentration was not only a predictor of the presence of acute HCA, but its concentration also correlated with the severity of acute HCA. The higher the intensity of IAI, the worse the degree of acute HCA in preterm gestation.

Maternal vitamin D status and spontaneous preterm birth by placental histology in the US Collaborative Perinatal Project

The objective of this study was to determine the association between maternal 25-hydroxyvitamin D (25(OH)D) and the risk of spontaneous preterm birth (sPTB) before 35 weeks' gestation. A random subcohort from the US Collaborative Perinatal Project (1959-1965) was sampled (n = 2,629) and augmented with all remaining cases of sPTB before 35 weeks' gestation for a total of 767 cases. Banked serum samples collected at 26 weeks' gestation or earlier were assayed for 25(OH)D. Constructs for vascular histology and inflammatory histology were developed from placental pathology examinations. There was no relationship between 25(OH)D and sPTB among white women. Among nonwhite mothers, serum 25(OH)D levels of 30-<50, 50-<75, and ≥75 nmol/L were associated with reductions of 1.0-1.6 cases of sPTB per 100 live births and 20%-30% reductions in risk of sPTB compared with 25(OH)D levels less than 30 nmol/L after adjustment for prepregnancy body mass index (weight (kg)/height (m)(2)), season, and other confounders. This association was driven by inflammation-mediated cases of sPTB and sPTB cases without placental lesions. A sensitivity analysis for unmeasured confounding by exercise, fish intake, and skin color suggested some bias away from the null in the conventional results, but conclusions were generally supported. The vitamin D-sPTB relationship should be examined in modern cohorts with detailed data on skin pigmentation and other covariates.

Fetal placental inflammation is associated with poor neonatal growth of preterm infants: a case-control study

OBJECTIVE

To determine whether there is an association between histological chorioamnionitis (HCA) and postnatal growth of preterm infants in the neonatal period.

METHOD

This case-control study is part of a larger prospective histological study on placentas performed in all deliveries prior to 32 weeks of gestation. Eligible cases involved all placentas with a diagnosis of HCA. Control subjects were those without HCA, matched 1:1 with case subjects according to gestational age (±1 week). Placental inflammatory status and serial weight gain were analyzed for all infants during the first four postnatal weeks. Based on placental inflammation extension, HCA was defined as maternal HCA (MHCA) or fetal HCA (FHCA).

RESULTS

Of the 320 mother-infant pairs, 71 (22.1%) presented with HCA (27 MHCA and 44 FHCA). Decreases in weight gain at 21 and 28 days were associated with the presence of FHCA (β coefficient ± SE = -4.40 ± 2.21, p = 0.05 and -6.92 ± 2.96, p = 0.02, respectively), whereas no significant differences were found between MHCA and no-HCA groups. FHCA and MHCA were not identified as risk factors of weekly weight gain, after adjusting for possible confounders (maternal ethnicity, parity, smoking during pregnancy, infant gender, IUGR status, SGA status, antenatal steroids, total fluid intake, late-onset sepsis, BPD).

CONCLUSIONS

We found an association between fetal placental inflammation and poor neonatal growth but we were not able to identify a specific week wherein weight gain could be mostly affected. Placental findings may be used to identify preterm infants at risk of postnatal growth failure.

Contribution of risk factors to extremely, very and moderately preterm births - register-based analysis of 1,390,742 singleton births

BACKGROUND

Preterm birth, defined as birth occurring before 37 weeks gestation, is one of the most significant contributors to neonatal mortality and morbidity, with long-term adverse consequences for health, and cognitive outcome.

OBJECTIVE

The aim of the present study was to identify risk factors of preterm birth (≤36+6 weeks gestation) among singleton births and to quantify the contribution of risk factors to socioeconomic disparities in preterm birth.

METHODS

A retrospective population-based case-control study using data derived from the Finnish Medical Birth Register. A total population of singleton births in Finland from 1987-2010 (n = 1,390,742) was reviewed.

RESULTS

Among all singleton births (n = 1,390,742), 4.6% (n = 63,340) were preterm (<37 weeks), of which 0.3% (n = 4,452) were classed as extremely preterm, 0.4% (n = 6,213) very preterm and 3.8% (n = 54,177) moderately preterm. Smoking alone explained up to 33% of the variation in extremely, very and moderately preterm birth incidence between high and the low socioeconomic status (SES) groups. Reproductive risk factors (placental abruption, placenta previa, major congenital anomaly, amniocentesis, chorionic villus biopsy, anemia, stillbirth, small for gestational age (SGA) and fetal sex) altogether explained 7.7-25.0% of the variation in preterm birth between SES groups.

CONCLUSIONS

Smoking explained about one third of the variation in preterm birth groups between SES groups whereas the contribution of reproductive risk factors including placental abruption, placenta previa, major congenital anomaly, amniocentesis, chorionic villus biopsy, anemia, stillbirth, SGA and fetal sex was up to one fourth.

Chorioamnionitis and prematurity: a critical review

Chorioamnionitis is the inflammatory response to an acute inflammation of the membranes and chorion of the placenta. We provide a critical review of the relationship between chorioamnionitis and the risk of prematurity and adverse maternal-fetal outcome. Chorioamnionitis results as a major risk factor for preterm birth and its incidence is strictly related to gestational age. It is associated with a significant maternal, perinatal and long-term adverse outcomes. The principal neonatal complications are neonatal sepsis, pneumonia, bronchopulmonary dysplasia, perinatal death, cerebral palsy and intraventricular hemorrhage. The role in neonatal outcome is still controversial and more conclusive studies could clarify the relationship between chorioamnionitis and adverse neonatal outcome. Maternal complications include abnormal progression of labour, caesarean section, postpartum hemorrhage, abnormal response after use of oxytocin and placenta abruption. Prompt administration of antibiotics and steroids could improve neonatal outcomes.

Histologic chorioamnionitis at term: implications for the progress of labor and neonatal wellbeing

OBJECTIVE

The aim of the present study was to evaluate: i) the rate of histologic chorioamnionitis in relation to the onset of labor and mode of delivery; ii) influence of clinical parameters on the risk of histologic chorioamnionitis in laboring women; iii) neonatal outcome in relation to histologic chorioamnionitis.

METHODS

A cohort study was conducted on 395 healthy women at term, with singleton uneventful pregnancy, of which 195 with spontaneous onset of labor and 200 with elective cesarean section. All placentas, collected after delivery, were examined for the diagnosis of histologic chorioamnionitis. Mode of delivery, presence of bacterial infection of placenta and membranes, maternal clinical parameters and neonatal outcome were recorded.

RESULTS

The rate of histologic chorioamnionitis in women with spontaneous onset of labor was significantly higher than in those experiencing elective cesarean section (28.7% vs. 11.5%). Nulliparity and the duration of labor were independent variables associated with acute histologic chorioamnionitis. The presence of histologic chorioamnionitis did not affect neonatal outcome.

CONCLUSIONS

The present study showed a highest rate of histological chorionamniositis in women delivering after spontaneous onset of term labor, although the mode of delivery either vaginally or by emergency cesarean section was not influenced by the presence of this pathological condition.

Histological chorioamnionitis is associated with cerebral palsy in preterm neonates

OBJECTIVE

To determine the interaction between histological chorioamnionitis and unexplained neonatal cerebral palsy among low birth weight infants.

STUDY DESIGN

We studied 141 preterm infants below 1500 g delivered between 2000 and 2010. Clinical data, neonatal neuroimaging, laboratory results, the histopathological features of the placenta and gastric smear within the first hour of delivery, were evaluated.

RESULTS

Cerebral palsy was detected in 11 out of 141 preterm newborns (7.8%). The incidence of silent histological chorioamnionitis was 33.6% (43 of 128 cases). Chorioamniontis was significantly associated with the risk of unexplained cerebral palsy (p=0.024). There were also significant correlations between maternal genital infections and chorioamnionitis (p=0.005), and between maternal infections and a positive smear of neonatal gastric aspirates (p=0.000). The rate of cesarean section was 67.4% (95 out of 141 deliveries), and elective cesarean section was performed in 68 cases.

CONCLUSION

Intrauterine exposure to maternal infection was associated with a marked increase in the risk of cerebral palsy in preterm infants.

Autism risk in small- and large-for-gestational-age infants

OBJECTIVE

We sought to determine whether small-for-gestational age (SGA) and large-for-gestational age (LGA) birthweights increase autism risk.

STUDY DESIGN

This was a retrospective cohort analysis comparing children with autism (n = 20,206) within a birth cohort (n = 5,979,605). Stratification by sex and birthweight percentile (SGA, <5th or 5-10th percentile; appropriate size for gestational age [GA], >10th to <90th percentile; LGA, either 90-95th or >95th percentile) preceded Cochran-Mantel-Haenszel analysis for GA effect, and multivariate analysis.

RESULTS

Autism risk was increased in preterm SGA (<5th percentile) infants 23-31 weeks (adjusted odds ratio [aOR], 1.60; 95% confidence interval [CI], 1.09-2.35) and 32-33 weeks (aOR, 1.83; 95% CI, 1.16-2.87), and term LGA (>95th percentile) infants 39-41 weeks (aOR, 1.16; 95% CI, 1.08-1.26), but was decreased in preterm LGA infants 23-31 weeks (aOR, 0.45; 95% CI, 0.21-0.95).

CONCLUSION

SGA was associated with autism in preterm infants, while LGA demonstrated dichotomous risk by GA, with increased risk at term, and decreased risk in the premature infants. These findings likely reflect disparate pathophysiologies, and should influence prenatal counseling, pediatric autism screening, and further autism research.

The frequency and risk factors of funisitis and histologic chorioamnionitis in pregnant women at term who delivered after the spontaneous onset of labor

OBJECTIVE

To examine the frequency and risk factors of funisitis and histologic chorioamnionitis in the placentas of term pregnant women who delivered after the spontaneous onset of labor.

METHODS

The frequency of funisitis and histologic chorioamnionitis was examined in consecutive pregnant women at term with singleton pregnancies who delivered after the spontaneous onset of labor. Nonparametric statistics were used for data analysis.

RESULTS

(1) The frequency of funisitis and histologic chorioamnionitis was 6.7% (88/1316) and 23.6% (310/1316), respectively; (2) Patients with funisitis had significantly higher rates of nulliparity, regional analgesia, operative vaginal delivery, longer duration of labor and rupture of membranes (ROM), and higher gestational age and birthweight than those without funisitis (p < 0.05 for each); (3) Patients with histologic chorioamnionitis had significantly higher rates of nulliparity, oxytocin augmentation, regional analgesia, cesarean section or operative vaginal delivery, longer duration of labor and ROM, and higher gestational age and birthweight than those without histologic chorioamnionitis (p < 0.05 for each); (4) Multiple logistic regression analysis indicated that the longer the duration of labor, the higher the risk of funisitis, and that nulliparity and the duration of labor significantly increased the odds of histologic chorioamnionitis (p < 0.05 for each).

CONCLUSION

The longer the duration of labor, the higher the risk of funisitis and histologic chorioamnionitis in pregnant women at term who delivered after the spontaneous onset of labor.

Placental pathology in fetal growth restriction

OBJECTIVES

One of the causes of intrauterine fetal growth restriction (FGR) can be pathology of the placenta. The aim of this study was to compare macroscopic and microscopic changes of the placentas from intrauterine growth restricted fetuses with those from normally developed fetuses, in order to test the hypothesis that vascular damage due to decreased maternal vascular perfusion may be responsible for FGR.

STUDY DESIGN

Between May 2007 and December 2008 we performed detailed macroscopic and histological examination of singleton placentas of 50 consecutive neonates with fetal growth restriction (FGR group) and compared them to 50 normal fetuses, born next to an FGR case, as a control group.

RESULTS

Gestational age, birth weight, spontaneous delivery rate, mean weight of the placenta and the fetal-placental weight ratio were all lower in the FGR group than in the control group (p<0.05). Thickening of the villous trophoblastic basal membrane, incidence of villous infarction, presence of thrombi or haematomas and the incidence of villitis were more common in the FGR group than in the controls (p<0.05). There were, however, no significant differences in perivillous fibrin deposition, stromal fibrosis and cytotrophoblast proliferation between the groups. In FGR women who smoked, intervillous haematomas and villous infarction were more common (p<0.05) than in controls.

CONCLUSIONS

All macroscopic and microscopic pathological changes associated with FGR were directly linked to reduction of placental blood flow. As smoking is a main risk factor for these placental abnormalities these results emphasize the need to persuade women to quit smoking not only during pregnancy, but even better long before pregnancy.

Placental inflammatory response is associated with poor neonatal growth: preterm birth cohort study

OBJECTIVE

We sought to determine whether placental markers of intrauterine inflammation were associated with poor weight gain among premature infants in the neonatal period.

METHODS

We reviewed 697 preterm births prospectively enrolled as part of an ongoing molecular epidemiological study. Placental markers and serial weight gain were analyzed for premature infants who were hospitalized for >/=21 days (N = 256). Placentas were examined for maternal inflammatory response (MIR), defined as subchorionitis, chorioamnionitis, deciduitis, or free membranitis, and fetal inflammatory response (FIR), defined as inflammation extending to the umbilical cord or chorionic plate. Multivariate linear regression and stratified analyses were performed.

RESULTS

Decreases in weight gain at day 21 were associated with the presence of either MIR or FIR (beta coefficient = -4.63 +/- 1.41; P = .001). The association was stronger with FIR than MIR (P for trend = .0027) and persisted in the remaining hospitalized infants at day 28 (n = 223; beta coefficient = -5.53 +/- 1.85; P = .0028). Mean body weights were similar among the 3 groups by corrected age of 36 weeks or discharge, whichever came first. Associations between placental inflammation and poor growth persisted among infants with prenatal corticosteroid exposure and/or neonatal complications and remained marginally significant in the nonexposed groups. Among infants without intrauterine growth restriction, significant association persisted (n = 186; beta coefficient = -5.68 +/- 1.56; P = .0003).

CONCLUSIONS

Placental inflammation is associated with poor neonatal growth. MIR and FIR may be useful markers for identifying infants at risk for postnatal growth failure.

Subclinical histologic chorioamnionitis and related clinical and laboratory parameters in preterm deliveries

BACKGROUND

Histologic chorioamnionitis (HCA) is associated with preterm delivery and with neonatal morbidity and mortality. Because HCA is usually subclinical, histologic examination of the placenta is essential for confirmatory diagnosis. In the present study, the correlations between subclinical HCA and relevant clinical and laboratory parameters were analyzed.

METHODS

This was a retrospective study. We reviewed the placental histopathologic findings and the charts of patients who were admitted to our neonatal intensive care unit after delivery and their mothers between January 2007 and March 2008. A total of 77 preterm infants [gastational age (GA): 32.2 3.4 weeks, birth weight (BW): 1718 +/- 554 g] were categorized as group A with histologic evidence of placental inflammation (n=27) or group B without histologic evidence of placental inflammation (n=50). Placental histology was studied to identify the presence of inflammatory states such as chorioamnionitis, funisitis and deciduitis. Laboratory parameters including complete blood count, differential count, and C-reactive protein (CRP) level of mothers and initial arterial blood gas, glucose Level and mean blood pressure of the infants were documented. Gestational age, Apgar score, history of prolonged premature rupture of membrane (prolonged PROM), gestational diabetes mellitus, meconium-stained amniotic fluid, pregnancy-induced hypertension and signs of pre-eclampsia were also collected as clinical parameters. All data were analyzed using independent t tests and Fisher's exact test, as appropriate.

RESULTS

Group A newborns had a significantly lower gestational age (30.8 +/- 4.1 weeks vs. 33.0 +/- 2.6 weeks, p < 0.05) and higher CRP level (0.56 +/- 0.92 mg/dL vs. 0.12 +/- 0.14 mg/dL, p < 0.05), together with higher maternal WBC count (13,002 +/- 4344/microL vs. 10,850 +/- 3722/microL, p < 0.05) and higher rate of prolonged PROM [14/27 (51.85%) vs. 8/37 (21.62%), p < 0.05] compared with group B newborns.

CONCLUSION

We found that HCA was significantly correlated with lower gestational age, higher CRP level of preterm infants, higher maternal WBC count, and a higher rate of prolonged PROM. Our results demonstrate a significant association between HCA with an elevated CRP level in preterm infants. These findings further confirmed the association between maternal inflammation and preterm deliveries.

Histological characteristics of singleton placentas delivered before the 28th week of gestation

AIMS

The placenta is a record of the fetal environment and its examination may provide information about the baby's subsequent growth and development. We describe the histological characteristics of 947 singleton placentas from infants born between 23 and 27 weeks gestation.

METHODS

Consent was obtained from mothers who delivered before 28 weeks (clinical estimate). We evaluated the gross and histopathological features of the placenta and assessed pair-wise correlations between variables.

RESULTS

Lesions of uteroplacental circulation (abruption, extensive infarction or thrombosis, marked basal or perivillous fibrin deposition, increased syncytial knots) were inversely related to those associated with inflammation of the membranes and cord. Earlier age favoured inflammatory variables, while older age favoured characteristics attributed to impaired blood flow. We observed inflammation of the chorionic plate in 43%, the cord in 19%, and of chorionic plate vessels in 30%. Of the placentas with umbilical cord inflammation, 8% had no inflammation of the chorionic plate.

CONCLUSIONS

This study population is unique in its size and recruitment by gestational age rather than birth weight. Inflammation occurred frequently, but not in placentas that had characteristics of vasculopathy. The prevalence of inflammation decreased with increasing gestational age, while vasculopathy increased. Funisitis need not be accompanied by chorionic inflammation.

Infection and fetal neurologic injury

PURPOSE OF REVIEW

Antepartum fetal exposure to infection/inflammation is a more important risk factor for brain injury than intrapartum hypoxia in both the term and preterm neonate. Such preexisting infection/inflammation might also provide the platform for subsequent intrapartum hypoxic-ischaemic damage. This review will discuss the complex interaction between fetal inflammatory response and neurotoxicity, and focus on the clinical implications of the synergistic interaction between infection/inflammation and hypoxia-ischaemia.

RECENT FINDINGS

Current evidence indicates that inflammatory mediators are directly neurotoxic, and also sensitize the fetal brain tissue to a greater magnitude of damage by subsequent hypoxia-ischaemia by lowering the threshold at which hypoxia initiates neuronal cell apoptosis/cell death.

SUMMARY

Further studies are urgently needed to characterize the fetuses at risk of damage, the duration of exposure required to cause injury, the influence of gestational age and whether Caesarean section may be protective. Until then clinicians should maintain a high level of surveillance in labours complicated by infection and avoid additional exposure to hypoxic-ischaemic insults.

Placenta and fetal growth restriction

The placenta, as the vector for all maternal-fetal oxygen and nutrient exchange, is a principal influence on birthweight. Placental weight summarizes laterally expanding growth of the chorionic disc, and villous arborization yielding the nutrient exchange surface. These different growth dimensions alter fetoplacental weight ratio and ponderal index, and thus may modify placental functional efficiency. The placenta may show a range of histopathologies, some of which are also associated with fetal growth restriction. Different fetal intrinsic abilities to compensate for gross and histo-pathology may clarify the imperfect relationships between fetal growth and both intrauterine pathology, and the long-term health risks associated with poor fetal growth.

Fatores de risco associados ao nascimento de recém-nascidos de muito baixo peso em uma população de baixa renda

Identificar os fatores de risco associados ao nascimento de recém-nascidos de muito baixo peso no Hospital Geral de Caxias do Sul, Rio Grande do Sul, Brasil. Estudo de caso-controle, abrangendo 200 recém-nascidos com peso entre 500 e 1.499g (casos) e 400 recém-nascidos com peso entre 3.000 e 3.999g (controles). Incluídos recém-nascidos de gestação única, cujas mães não realizaram pré-natal ou o fizeram na rede pública. A variável dependente foi o peso de nascimento e as variáveis independentes foram as sócio-econômicas, educacionais, gestacionais e do parto. Utilizou-se a análise univariada e multivariada, com nível de significância de 5%. A mortalidade dos recém-nascidos de muito baixo peso foi de 32,5%. O limite de viabilidade dos recém-nascidos foi 600g de peso e 26 semanas de idade gestacional. As variáveis relacionadas com o nascimento prematuro foram: idade materna > 35 anos (p = 0,01), ausência de pré-natal (p < 0,0001), doenças na gestação (p = 0,03), hipertensão materna (p = 0,007), internação na gestação (p < 0,0001) e filho anterior de baixo peso ao nascer (p < 0,0001). Muitos nascimentos prematuros ocorreram por causas evitáveis.

Oral Clindamycin and Histologic Chorioamnionitis in Women With Abnormal Vaginal Flora

OBJECTIVE

Oral clindamycin reduced late miscarriage and preterm birth in asymptomatic women with bacterial vaginosis or intermediate flora. We investigated whether clindamycin reduced the incidence of histologic chorioamnionitis as a mechanism for these beneficial effects.

METHODS

This was a subanalysis of 126 participants from a larger randomized controlled trial. We compared the incidence of histologic chorioamnionitis between the clindamycin and placebo groups. Histologic chorioamnionitis was diagnosed by the presence of polymorphonuclear leukocytes, separately in the amnion and chorion, decidua, fetal surface of the placenta, the walls of fetal chorionic vessels, umbilical cord, or in the subchorionic fibrin layer. Microbiologic cultures were done on swabs from the space between the chorion and amnion layers.

RESULTS

Histopathologic results were available for 122 placentas, 62 (51%) and 60 (49%) in the clindamycin and placebo groups, respectively. There were no significant differences in inflammation between the groups in the decidua (41% compared with 43%), membranes (25% compared with 41%), fetal vessels (16% compared with 14%), or subchorionic fibrin (32% compared with 34%). Adjusting for gestational age, ethnic origin, or history of miscarriage did not alter the results. There were no significant differences in the outcomes of pregnancy between women with and without inflammation, either before or after adjustment for treatment group.

CONCLUSION

Although oral clindamycin reduced late miscarriage and preterm birth in women with abnormal vaginal flora, this effect is unlikely to be mediated through a reduction in the incidence of histologic chorioamnionitis. The relatively small size of the groups, however, does not allow us to rule out a real effect, especially given the lower rate of membrane inflammation observed in the clindamycin group.

LEVEL OF EVIDENCE

I.

Effect of pro-inflammatory cytokines on expression and activity of 11beta-hydroxysteroid dehydrogenase type 2 in cultured human term placental trophoblast and human choriocarcinoma JEG-3 cells

OBJECTIVE

11Beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) is thought to act as a placental barrier protecting the fetus from high levels of maternal cortisol. On the other hand, intrauterine infection is one of the main causes of preterm birth and adverse fetal outcome, and pro-inflammatory cytokines may contribute to these adverse effects. However, the effect of pro-inflammatory cytokines on 11beta-HSD2 is still not clear. Therefore, we have evaluated the effect of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) on 11beta-HSD2 in cultured human placental trophoblast and in human choriocarcinoma JEG-3 cells.

METHODS

Placental trophoblast cells were isolated from human term placenta. Placental trophoblast cells and JEG-3 cells were treated with TNF-alpha (0.1-10 ng/mL) or IL-1beta (0.1-10 ng/mL). Real-time reverse transcription polymerase chain reaction and Western blot were used to study the regulation of 11beta-HSD2 expression. 11beta-HSD2 activity was determined by measuring the rate of cortisol to cortisone conversion in the culture medium using thin-layer chromatography (TLC).

RESULTS

In placental trophoblast, TNF-alpha and IL-1beta down-regulated 11beta-HSD2 mRNA expression and activity (both P <.05). The protein level was decreased only with IL-1beta (P <.05). In JEG-3 cells, 11beta-HSD2 mRNA was decreased by TNF-alpha but up-regulated by IL-1beta, with no significant change in protein expression and activity.

CONCLUSION

Our results suggest caution in interpreting data using JEG-3 cells. However, our studies with primary trophoblast suggest that TNF-alpha and IL-1beta may increase the amount of cortisol crossing to the placenta and fetal circulation by attenuating 11beta-HSD2 activity, potentially contributing to preterm labor and altered fetal outcome in uterine infection.

Placental assessment: Simple techniques to enhance best practice

BACKGROUND

The placenta provides a 'diary' of the pregnancy. The information provided from pathological assessment of the placenta may provide important clinical information for both the mother and the neonate.

AIMS

To develop tools to ensure histopathological assessment of appropriate placentas and uniform provision of clinical history to pathologists to enable clinicopathological assessment.

METHODS

A placenta information form was devised that included the following clinical criteria: gestational age, prolonged rupture of membranes at term, suspected maternal/fetal bacterial or viral infection, swabs taken for culture, intrauterine growth restriction, perinatal death, pre-eclampsia, essential hypertension, diabetes, placenta praevia, multiple pregnancy and cytogenetics. A table was introduced into the midwifery placenta policy indicating clinical criteria for microbiology, histopathological or cytogenetic assessment. A colourful reminder poster was designed and placed in the delivery suite and education sessions were provided. Six-month review periods were performed prior to and following the two interventions.

RESULTS

The number of placentas submitted for histopathological examination (and meeting the inclusion criteria) increased from 41 (120/296) to 61% (161/266) following the initial interventions and to 82% (262/319) with the introduction of the reminder poster and education sessions. Clinically relevant placental pathology was found in 55 (64%) of cases in these time intervals. Comprehensive clinical history on the pathology report improved from 45 to 98% over the assessment time.

CONCLUSIONS

Valuable information on a pregnancy can be provided by ensuring histopathological examination of appropriate placentas with the simple introduction of placental information sheets, updated midwifery policy, education sessions and a colourful reminder poster.

Early postnatal changes in the perfusion index in term newborns with subclinical chorioamnionitis

BACKGROUND

Chorioamnionitis (HCA) in term newborns is often subclinical and associated with neonatal morbidity and mortality.

OBJECTIVE

To assess the value of the pulse oximetry perfusion index (PI) in the early prediction of subclinical HCA in term newborns.

METHODS

PI cut-off values were first identified in 51 term newborns with HCA and 115 matched controls, retrospectively categorised on the basis of placental histology (study phase 1). The PI thresholds obtained were subsequently tested on an unselected case series of 329 prospectively recruited, term newborns (study phase 2). PI was evaluated during the first five minutes after delivery. Initial illness severity and short term clinical outcomes were determined.

RESULTS

In study phase 1, newborns with HCA had lower PI one and five minutes (p<0.0001) after delivery, lower one minute Apgar score (p = 0.017), lower cord blood base excess (p = 0.0001), together with higher rates of admission to neonatal intensive care unit (p = 0.0001) and endotracheal intubation (p = 0.017), and higher SNAP-PE (p<0.0001) and NTISS (p<0.0001) scores than those without HCA. In the prospective validation phase of the study, the PI cut-off values generated (one minute < or =1.74, five minutes < or =2.18) showed 100% sensitivity, 99.4% specificity, 93.7% positive predictive value, and 100% negative predictive value in identifying subclinical HCA. Early identification of HCA was associated with a decreased rate of admission to intensive care (p = 0.012), as well as lower initial illness severity (p< or =0.0001) and therapeutic intensity (p = 0.0006) than the newborns with HCA in phase 1.

CONCLUSION

These findings suggest that early PI monitoring is helpful in identifying HCA in term newborns.

Preterm labor, preterm premature rupture of membranes, and chorioamnionitis

In this article, the author reviews the etiology and biochemical links between infection and preterm birth, the problem of preterm birth, and the management of infection-related risks of preterm birth. The management section reviews current opinions regarding prophylactic antibiotic therapy in the prevention of preterm birth, adjunctive antibiotic therapy in the treatment of preterm labor with and without rupture of membranes, and antibiotic therapy of intra-amniotic infection (clinical chorioamnionitis, IAI). Finally, the article reviews the risk of neurodevelopmental handicap potentially associated with IAI.

Histologic chorioamnionitis and severity of illness in very low birth weight newborns

OBJECTIVE

Estimating the risk of in-hospital mortality in the neonatal intensive care unit provides important information for health care providers, and several neonatal illness severity scores have been developed. Histologic chorioamnionitis (HCA) is a known cause of neonatal morbidity and mortality. To date, the relationship between HCA and neonatal illness severity scores has not been rigorously tested. In this study, the relationships among HCA, initial illness severity, and neonatal outcomes were analyzed in very low birth weight (VLBW) newborns admitted to the neonatal intensive care unit.

DESIGN

Prospective.

SETTING

Neonatal intensive care unit.

PATIENTS

A total of 116 VLBW inborn infants (gestational age, 28.1 +/- 2.82 wks; birth weight, 1009 +/- 312 g) were categorized as HCA-positive (n = 67) and HCA-negative (n = 49).

INTERVENTIONS

Placental histology was performed to identify HCA. Illness severity evaluation included several different neonatal illness severity scores-Clinical Risk Index for Babies (CRIB), CRIB-II, Score for Neonatal Acute Physiology-II (SNAP-II), and Score for Neonatal Acute Physiology Perinatal Extension-II (SNAPPE-II)-as well as the recording of severe morbidity and in-hospital mortality.

MEASUREMENTS AND MAIN RESULTS

HCA-positive VLBW newborns showed significantly lower gestational age (p < .0001) and birth weight (p = .0010), together with higher CRIB, CRIB-II, SNAP-II, and SNAPPE-II scores at admission to the NICU (p </= .0001) and mortality rate (p = .0018) than HCA-negative infants. After adjustment for gender and gestational age in a multivariable logistic regression analysis, HCA was found to be an independent predictor of high illness severity: CRIB > 5 (odds ratio [OR], 21.37; 95% confidence interval [CI], 6.24-73.21); CRIB-II > 10 (OR, 56.17; 95% CI, 6.75-467.2); SNAP-II > 22 (OR, 43.05; 95% CI, 11.9-155.7), and SNAPPE-II > 42 (OR, 48.95; 95% CI, 10.18-235.4) (all p values <.0001).

CONCLUSIONS

Our findings indicate that HCA is a major predictor of morbidity and mortality in VLBW newborns.

Expression of IGR-IR and VEGF and trophoblastic proliferative activity in placentas from pregnancies complicated by IUGR

Intrauterine growth retardation (IUGR) is recognized as an important cause of low birth weight and elective preterm delivery. IUGR is associated with multiple causative factors, including placental dysfunction. The aim of this prospective study was to investigate the role of trophoblastic proliferative activity and type I insuline-like growth factor receptor (IGF-IR) and vascular endothelial growth factor (VEGF) expressions in the pathogenesis of IUGR. Immunohistochemistry using VEGF, IGF-IR, and Ki-67 antibodies was performed on formalin-fixed placental tissues of third-trimester pregnancies complicated by IUGR (n = 19) and pregnancies with appropriately grown fetuses (n = 27). In addition, histopathological examination of the placentas was performed, and histological findings were categorized into three groups: utero-placental vascular pathologies (UPVP), coagulation-related pathologies, and chronic inflammation. Statistical analysis revealed that villous trophoblastic IGF-IR immunostaining was significantly weaker in placentas with IUGR (p < 0.001), whereas trophoblastic Ki-67 proliferative index and VEGF immunoscoring did not show any significant difference. Histologically, UPVP and chronic inflammation were significant findings in placentas with IUGR (p = 0.04 and p = 0.04, respectively). In addition, placentas were significantly smaller in the IUGR group (p < 0.001). We conclude that villous trophoblastic IGF-IR expression may play a significant role in the pathogenesis of IUGR, and histopathological examination of placentas in pregnancies complicated by IUGR may yield significant findings. In contrast, based on our findings, trophoblastic proliferation and VEGF expression are unlikely to be significant parameters in the pathogenesis of IUGR.

Early postnatal skin colour changes in term newborns with subclinical histological chorioamnionitis

Chorioamnionitis, a known risk factor for fetal and neonatal morbidity both in preterm and term newborns, is often subclinical. Earlier observations have linked skin colourimetry to neonatal illness severity and adverse neonatal outcome. Here, we tested the hypothesis that subclinical histological chorioamnionitis is associated with early postnatal skin colour changes in term newborns. Skin colourimetry on ten body sites (forehead, cheek, forearm, palm, upper chest, abdomen, back, buttock, leg, and sole) was examined in 45 term infants with subclinical histological chorioamnionitis and 45 sex- and gestational age-matched controls, using a tristimulus portable colourimeter at 1, 5 and 10 min after birth. Infants with subclinical histological chorioamnionitis showed statistically significant early postnatal skin colourimetric differences, in nine and seven out of the ten body sites examined as compared to control newborns at 1 min (P< or =0.0092), 5 min (P< or =0.0081) and 10 min (P< or =0.0056) from birth, respectively. Skin colourimetry changes were associated with lower 1 min Apgar scores (P<0.0001), cord blood pH (P<0.0001), PaO2 (P<0.0001), and base excess (P<0.0001) values, together with higher cord blood PaCO2 (P=0.0001), NICU admissions (P=0.00076), endotracheal intubation in the delivery room (P=0.012), Neonatal Acute Physiology-Perinatal Extension (P<0.0001) and Neonatal Therapeutic Intervention Scoring System (P<0.0001) scores than the chorioamnionitis-negative infants.

CONCLUSION

These findings, compatible with early peripheral microcirculatory changes, indicate skin vasoconstriction as an early neonatal manifestation of subclinical chorioamnionitis.