RESUMO
OBJECTIVE: This study aimed to evaluate fetal biometrics as predictors of shoulder dystocia (SD) in a low-risk obstetrical population. STUDY DESIGN: Participants were enrolled as part of a U.S.-based prospective cohort study of fetal growth in low-risk singleton gestations (n = 2,802). Eligible women had liveborn singletons ≥2,500 g delivered vaginally. Sociodemographic, anthropometric, and pregnancy outcome data were abstracted by research staff. The diagnosis of SD was based on the recorded clinical impression of the delivering physician. Simple logistic regression models were used to examine associations between fetal biometrics and SD. Fetal biometric cut points, selected by Youden's J and clinical determination, were identified to optimize predictive capability. A final model for SD prediction was constructed using backward selection. Our dataset was randomly divided into training (60%) and test (40%) datasets for model building and internal validation. RESULTS: A total of 1,691 women (98.7%) had an uncomplicated vaginal delivery, while 23 (1.3%) experienced SD. There were no differences in sociodemographic or maternal anthropometrics between groups. Epidural anesthesia use was significantly more common (100 vs. 82.4%; p = 0.03) among women who experienced SD compared with those who did not. Amniotic fluid maximal vertical pocket was also significantly greater among SD cases (5.8 ± 1.7 vs. 5.1 ± 1.5 cm; odds ratio = 1.32 [95% confidence interval: 1.03,1.69]). Several fetal biometric measures were significantly associated with SD when dichotomized based on clinically selected cut-off points. A final prediction model was internally valid with an area under the curve of 0.90 (95% confidence interval: 0.81, 0.99). At a model probability of 1%, sensitivity (71.4%), specificity (77.5%), positive (3.5%), and negative predictive values (99.6%) did not indicate the ability of the model to predict SD in a clinically meaningful way. CONCLUSION: Other than epidural anesthesia use, neither sociodemographic nor maternal anthropometrics were significantly associated with SD in this low-risk population. Both individually and in combination, fetal biometrics had limited ability to predict SD and lack clinical usefulness. KEY POINTS: · SD unpredictable in low-risk women.. · Fetal biometry does not reliably predict SD.. · Epidural use associated with increased SD risk.. · SD prediction models clinically inefficient..
RESUMO
Monochorionic diamniotic twins share a single placenta and have intertwin vascular communications that link the circulatory systems of the twins together. Twin anemia-polycythemia sequence (TAPS) is an atypical form of twin-twin transfusion syndrome (TTTS) caused by net transfer of blood from one fetus to the other and is characterized by large intertwin hemoglobin differences in the absence of oligohydramnios and polyhydramnios. This condition may develop spontaneously (sTAPS) or as a result of residual vascular communications after prior laser surgery. Because of the relatively low prevalence and lack of clinical awareness, the natural history of sTAPS is unclear and the antenatal treatment remains controversial. Case series of sTAPS have described expectant management with timed delivery, intrauterine blood transfusion, and fetoscopic laser treatment. Favorable outcomes have been described in cases of uncomplicated sTAPS that underwent conservative measures. However, we believe that there may be a subgroup of high-risk or complicated sTAPS patients that may benefit from definitive treatment afforded by fetoscopic laser therapy. We describe 3 complicated cases of sTAPS successfully treated with selective laser photocoagulation of communicating vessels. In 2 of the cases, placental pathology identified thrombosed fetal vessels of the polycythemic twin.
Assuntos
Anemia/cirurgia , Transfusão Feto-Fetal/cirurgia , Fetoscopia/métodos , Terapia a Laser/métodos , Policitemia/cirurgia , Adulto , Transfusão de Sangue Intrauterina , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Resultado do TratamentoRESUMO
OBJECTIVE: The decision of whether to retain or remove a previously placed cervical cerclage in women who subsequently rupture fetal membranes in a premature gestation is controversial and all studies to date are retrospective. We performed a multicenter randomized controlled trial of removal vs retention of cerclage in these patients to determine whether leaving the cerclage in place prolonged gestation and/or increased the risk of maternal or fetal infection. STUDY DESIGN: A prospective randomized multicenter trial of 27 hospitals was performed. Patients included were those with cerclage placement at ≤23 weeks 6 days in singleton or twin pregnancies, with subsequent spontaneous rupture of membranes between 22 weeks 0 days and 32 weeks 6 days. Patients were randomized to retention or removal of cerclage. Patients were then expectantly managed and delivered only for evidence of labor, chorioamnionitis, fetal distress, or other medical or obstetrical indications. Management after 34 weeks was at the clinician's discretion. RESULTS: The initial sample size calculation determined that a total of 142 patients should be included but after a second interim analysis, futility calculations determined that the conditional power for showing statistical significance after randomizing 142 patients for the primary outcome of prolonging pregnancy was 22.8%. Thus the study was terminated after a total of 56 subjects were randomized with complete data available for analysis, 32 to removal and 24 to retention of cerclage. There was no statistical significance in primary outcome of prolonging pregnancy by 1 week comparing the 2 groups (removal 18/32, 56.3%; retention 11/24, 45.8%) P = .59; or chorioamnionitis (removal 8/32, 25.0%; retention 10/24, 41.7%) P = .25, respectively. There was no statistical difference in composite neonatal outcomes (removal 16/33, 50%; retention 17/30, 56%), fetal/neonatal death (removal 4/33, 12%; retention 5/30, 16%); or gestational age at delivery (removal mean 200 days; retention mean 198 days). CONCLUSION: Statistically significant differences were not seen in prolongation of latency, infection, or composite neonatal outcomes. However, there was a numerical trend in the direction of less infectious morbidity, with immediate removal of cerclage. These findings may not have met statistical significance if the original sample size of 142 was obtained, however they provide valuable data suggesting that there may be no advantage to retaining a cerclage after preterm premature rupture of membranes and a possibility of increased infection with cerclage retention.
Assuntos
Cerclagem Cervical , Corioamnionite/prevenção & controle , Ruptura Prematura de Membranas Fetais/terapia , Nascimento Prematuro/prevenção & controle , Adulto , Cerclagem Cervical/efeitos adversos , Corioamnionite/etiologia , Feminino , Humanos , Gravidez , Resultado do TratamentoRESUMO
OBJECTIVE: We sought to determine whether prophylactic treatment with 17-alpha-hydroxyprogesterone caproate (17Pc) in twin pregnancy will reduce neonatal morbidity (primary outcome) by prolonging pregnancy (secondary outcome). STUDY DESIGN: This was a double-blind, randomized clinical trial. Mothers carrying dichorionic-diamniotic twins were randomly assigned (in a 2:1 ratio) to weekly injections of 250 mg of 17Pc or placebo, starting at 16-24 weeks and continued until 34 weeks. RESULTS: In all, 160 women were randomized to 17Pc and 80 to placebo. Composite neonatal morbidity occurred with similar frequency in the 17Pc and placebo groups (14% vs 12%, respectively, P = .62). Mean gestational age at delivery was not affected by 17Pc (35.3 vs 35.9 weeks, P = .10), but a 3-day difference in median gestational age favored placebo (P = .02). There were no perinatal deaths with 17Pc and 3 with placebo. CONCLUSION: In twin pregnancy, prophylactic treatment with 17Pc did not prolong gestation or reduce neonatal morbidity.
Assuntos
Hidroxiprogesteronas/uso terapêutico , Gravidez Múltipla , Nascimento Prematuro/prevenção & controle , Progestinas/uso terapêutico , Caproato de 17 alfa-Hidroxiprogesterona , Adulto , Método Duplo-Cego , Feminino , Humanos , Morbidade , Gravidez , Resultado da GravidezRESUMO
We report a case of a rudimentary horn pregnancy with herniation of a fetal arm and umbilical cord into the main uterine cavity that presented as an incidental finding on a routine second-trimester ultrasound scan. We also review the literature that guides the diagnosis and management of these rare complicated pregnancies.
Assuntos
Doenças Fetais/diagnóstico , Hérnia/diagnóstico , Complicações na Gravidez/diagnóstico , Útero/anormalidades , Adulto , Braço , Cesárea , Edema/patologia , Evolução Fatal , Feminino , Ruptura Prematura de Membranas Fetais , Humanos , Imageamento Tridimensional , Achados Incidentais , Imageamento por Ressonância Magnética , Gravidez , Segundo Trimestre da Gravidez , Ultrassonografia Pré-Natal , Cordão Umbilical , Útero/patologiaRESUMO
OBJECTIVE: To test whether 17 alpha-hydroxyprogesterone caproate (17P) will reduce neonatal morbidity by increasing gestational age at delivery in triplet pregnancies. STUDY DESIGN: Double-blind, randomized clinical trial. Mothers carrying trichorionic-triamniotic triplets were randomly assigned (in a 2:1 ratio) to weekly injections of 250 mg of 17P or placebo, starting at 16-22 weeks and continued until 34 weeks. Primary outcome was composite neonatal morbidity. RESULTS: Fifty-six women were randomized to 17P and 25 to placebo. Composite neonatal morbidity occurred with similar frequency in the 17P and placebo groups (38% vs 41%, respectively; P = .71). Mean gestational age at delivery was not affected by 17P (31.9 vs 31.8 weeks; P = .36). There were 13 midtrimester fetal losses with 17P vs none with placebo (P < .02). CONCLUSION: In triplet pregnancy, prophylactic treatment with 17P did not reduce neonatal morbidity or prolong gestation but was associated with increased midtrimester fetal loss.
Assuntos
17-alfa-Hidroxiprogesterona/uso terapêutico , Gravidez de Alto Risco , Gravidez Múltipla , Nascimento Prematuro/prevenção & controle , Trigêmeos , Aborto Espontâneo/epidemiologia , Adulto , Método Duplo-Cego , Feminino , Morte Fetal/epidemiologia , Idade Gestacional , Humanos , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Gravidez , Complicações na Gravidez/epidemiologiaRESUMO
OBJECTIVE: To determine if the sonographic difference of > or = 2.6 cm between the fetal abdominal diameter (AD) and biparietal diameter (BPD), a proxy for fetal asymmetry, has an association with shoulder dystocia in nondiabetic women with suspected macrosomia. STUDY DESIGN: A retrospective cohort study was performed in 3 Southern California tertiary care hospitals. We identified patients in whom sonographic evaluation after 36 weeks' gestation demonstrated an estimated fetal weight > 4,000 g. Additional prenatal and delivery information was obtained from hospital records. RESULTS: We identified 159 subjects who met ultrasound criteria and underwent a vaginal delivery. The mean AD-BPD difference in the shoulder dystocia group was significantly greater than in the group without shoulder dystocia (2.76 +/- 0.59 vs. 2.37 +/- 0.56, p = 0.001). The adjusted OR of shoulder dystocia in the group with an AD-BPD difference > or = 2.6 was 3.67 (95% CI, 1.44-9.36). CONCLUSION: Significant discordance between the fetal head and abdomen appears to be associated with an increased rate of shoulder dystocia in a nondiabetic population with suspected macrosomia.
Assuntos
Distocia/diagnóstico por imagem , Macrossomia Fetal/diagnóstico por imagem , Ultrassonografia Pré-Natal , Adulto , Cefalometria , Feminino , Humanos , Razão de Chances , Gravidez , Estudos RetrospectivosRESUMO
Gastroschisis is a congenital, ventral wall defect associated with bowel evisceration. The defect is usually to the right of the umbilical cord insertion and requires postnatal surgical correction. The fetus is at risk for complications such as intrauterine growth restriction, preterm delivery, and intrauterine fetal demise. In addition, complex cases, defined by the presence of intestinal complications such as bowel atresia, stenosis, perforation, or ischemia, occur in up to one third of pregnancies affected by gastroschisis. As complex gastroschisis is associated with increased morbidity and mortality, research has focused on the prenatal detection of this high risk subset of cases. The purpose of this review is to discuss the prenatal, diagnostic approach to the identification of gastroschisis, to describe potential signs of complex gastroschisis on prenatal ultrasound, to review current guidelines for antepartum management and delivery planning, and to summarize results of both past and current intervention trials in fetuses with gastroschisis.
Assuntos
Parto Obstétrico/métodos , Terapias Fetais/métodos , Gastrosquise/diagnóstico por imagem , Gastrosquise/terapia , Assistência Perinatal/métodos , Ultrassonografia Pré-Natal , Feminino , Humanos , Recém-Nascido , GravidezRESUMO
BACKGROUND: Cornelia de Lange syndrome is a genetic disorder associated with delayed growth and characteristic facial features. There is no definitive biochemical or chromosomal marker for the prenatal diagnosis of this syndrome. We describe a case of Cornelia de Lange syndrome associated with an increased nuchal translucency in the first trimester. CASE: A large nuchal translucency was identified in a fetus during a first trimester ultrasound. Subsequent second- and third-trimester sonograms demonstrated severe fetal growth restriction, limb shortening, and abnormal facial features, despite normal fetal karyotype per chorionic villus sampling. Neonatal evaluation confirmed the diagnosis of Cornelia de Lange syndrome. CONCLUSION: Sonographic finding of an increased nuchal translucency in early pregnancy is associated with fetal aneuploidy and various structural and genetic abnormalities. Increased nuchal translucency may identify fetuses that require vigilant assessment, especially when found in association with other abnormalities.
Assuntos
Síndrome de Cornélia de Lange/diagnóstico por imagem , Doenças Fetais/diagnóstico por imagem , Pescoço/embriologia , Feminino , Humanos , Pescoço/diagnóstico por imagem , Gravidez , Primeiro Trimestre da Gravidez , Ultrassonografia Pré-NatalRESUMO
Behavioral perinatology is as an interdisciplinary area of research that involves conceptualization of theoretical models and conduct of empirical studies of the dynamic time-, place-, and context-dependent interplay between biological and behavioral processes in fetal, neonatal, and infant life using an epigenetic framework of development. The biobehavioral processes of particular interest to our research group relate to the effects of maternal pre- and perinatal stress and maternal-placental-fetal stress physiology. We propose that behavioral perinatology research may have important implications for a better understanding of the processes that underlie or contribute to the risk of three sets of outcomes: prematurity, adverse neurodevelopment, and chronic degenerative diseases in adulthood. Based on our understanding of the ontogeny of human fetal development and the physiology of pregnancy and fetal development, we have articulated a neurobiological model of pre- and perinatal stress. Our model proposes that chronic maternal stress may exert a significant influence on fetal developmental outcomes. Maternal stress may act via one or more of three major physiological pathways: neuroendocrine, immune/inflammatory, and vascular. We further suggest that placental corticotropin-releasing hormone (CRH) may play a central role in coordinating the effects of endocrine, immune/inflammatory, and vascular processes on fetal developmental outcomes. Finally, we hypothesize that the effects of maternal stress are modulated by the nature, duration, and timing of occurrence of stress during gestation. In this paper, we elaborate on the conceptual and empirical basis for this model, highlight some relevant issues and questions, and make recommendations for future research in this area.
Assuntos
Comportamento , Desenvolvimento Embrionário e Fetal/fisiologia , Complicações na Gravidez/psicologia , Efeitos Tardios da Exposição Pré-Natal , Estresse Psicológico/psicologia , Feminino , Humanos , Placenta/fisiologia , Placenta/fisiopatologia , Gravidez , Útero/fisiologia , Útero/fisiopatologiaRESUMO
OBJECTIVE: To identify perinatal variables associated with adverse outcomes in neonates prenatally diagnosed with gastroschisis. METHODS: A retrospective review was conducted of all inborn pregnancies complicated by gastroschisis within the five institutions of the University of California Fetal Consortium from 2007 to 2012. The primary outcome was a composite adverse neonatal outcome comprising death, reoperation, gastrostomy, and necrotizing enterocolitis. Variables collected included antenatal ultrasound findings, maternal smoking or drug use, gestational age at delivery, preterm labor, elective delivery, mode of delivery, and birth weight. Univariate and multivariate analysis was used to assess factors associated with adverse outcomes. We also evaluated the association of preterm delivery with neonatal outcomes such as total parenteral nutrition cholestasis and length of stay. RESULTS: There were 191 neonates born with gastroschisis in University of California Fetal Consortium institutions at a mean gestational age of 36 3/7±1.8 weeks. Within the cohort, 27 (14%) had one or more major adverse outcomes, including three deaths (1.6%). Early gestational age at delivery was the only variable identified as a significant predictor of adverse outcomes on both univariate and multivariate analysis (odds ratio 1.4, 95% confidence interval 1.1-1.8 for each earlier week of gestation). Total parenteral nutrition cholestasis was significantly more common in neonates delivered at less than 37 weeks of gestation (38/115 [33%] compared with 11/76 [15%]; P<.001). CONCLUSION: In this contemporary cohort, earlier gestational age at delivery is associated with adverse neonatal outcomes in neonates with gastroschisis. Other variables, such as antenatal ultrasound findings and mode of delivery, did not predict adverse neonatal outcomes.
Assuntos
Parto Obstétrico , Gastrosquise , Idade Gestacional , Trabalho de Parto Prematuro/epidemiologia , Complicações na Gravidez , Adulto , California/epidemiologia , Parto Obstétrico/efeitos adversos , Parto Obstétrico/métodos , Parto Obstétrico/estatística & dados numéricos , Enterocolite Necrosante/epidemiologia , Enterocolite Necrosante/etiologia , Feminino , Gastrosquise/complicações , Gastrosquise/diagnóstico , Gastrosquise/epidemiologia , Gastrostomia/estatística & dados numéricos , Humanos , Recém-Nascido , Tempo de Internação , Análise Multivariada , Avaliação de Resultados em Cuidados de Saúde , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Ultrassonografia Pré-Natal/estatística & dados numéricosRESUMO
BACKGROUND: Approximately 2% of all pregnancies are ectopic; of these, 4% are interstitial or cervical. There exists no clear consensus as to whether surgical or medical management is superior. CASE: We present three cases of advanced nonfallopian tube ectopic pregnancies from 6 to 8 weeks of gestation. Our first two cases were managed with a combined intrafetal, intra-amniotic and systemic approach using methotrexate and potassium chloride, whereas our third case was managed with an intra-amniotic approach alone. Our combined approach cases were successful, with resolution of human chorionic gonadotropin in 50 and 34 days, whereas our single approach case re-presented with bleeding requiring uterine artery embolization and operative removal of products of conception. CONCLUSION: Patients presenting with advanced interstitial or cervical pregnancies who are clinically stable can be offered medical management with a combined approach.
Assuntos
Abortivos não Esteroides/administração & dosagem , Metotrexato/administração & dosagem , Gravidez Ectópica/tratamento farmacológico , Abortivos não Esteroides/uso terapêutico , Adulto , Gonadotropina Coriônica/sangue , Feminino , Humanos , Metotrexato/uso terapêutico , Cloreto de Potássio/uso terapêutico , Compostos de Potássio/uso terapêutico , Gravidez , Embolização da Artéria Uterina , Hemorragia Uterina/etiologia , Hemorragia Uterina/terapia , Adulto JovemRESUMO
BACKGROUND: Fetal epignathus, a teratoma arising from the oropharynx that may be lethal, can be diagnosed prenatally. CASE: A 29-year-old woman, gravida 1, was evaluated for an elevated alpha-fetoprotein level. Imaging evaluation revealed a fetal epignathus without intracranial extension. Preterm labor necessitated delivery at 27 5/7 weeks of gestation with ex utero intrapartum treatment (EXIT) procedure using a classical incision. The neonate's small size and short umbilical cord required complete exteriorization to secure the airway. Pathology revealed an immature teratoma. CONCLUSION: Prenatal diagnosis of fetal epignathus is imperative so that all options can be discussed. An EXIT procedure may be necessary for airway management at birth. If preterm delivery is necessary, choice of uterine incision and fetal size are important factors to consider for a successful outcome.
Assuntos
Doenças Fetais/cirurgia , Neoplasias Orofaríngeas/cirurgia , Teratoma/cirurgia , Adulto , Cesárea , Feminino , Doenças Fetais/diagnóstico , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Neoplasias Orofaríngeas/diagnóstico , Gravidez , Nascimento Prematuro , Teratoma/diagnóstico , Ultrassonografia Pré-Natal , alfa-Fetoproteínas/metabolismoRESUMO
In stage V twin-twin transfusion syndrome (TTTS), up to 50% of surviving twins die or experience permanent disabilities, likely due to acute intertwin hemorrhage resulting in sudden severe anemia of the survivor. Although fetal middle cerebral artery (MCA) Doppler studies demonstrate strong correlation with fetal hemoglobin values, acute hemorrhagic events are more difficult to diagnose, and optimal timing of delivery of the survivor poses an obstetric dilemma. We report a case of newly diagnosed stage V TTTS at 28 weeks gestation, complicated by acute severe anemia diagnosed by significantly abnormal fetal MCA Doppler studies. The anemic twin was urgently delivered and is doing well without significant sequelae.
RESUMO
OBJECTIVE: To evaluate whether day-3 embryo morphology predicts euploidy. DESIGN: Retrospective. SETTING: Private IVF center. PATIENT(S): Subjects (n = 144) undergoing in vitro fertilization and preimplantation genetic diagnosis (PGD). INTERVENTION(S): Translate day-3 embryo characteristics into a standardized score. MAIN OUTCOME MEASURE(S): Day-3 embryo morphology score and PGD fluorescence in situ hybridization results for chromosomes: 13, 15, 16, 17, 18, 21, 22, X, and Y. RESULT(S): Of 1,043 biopsied blastomeres, 67% (n = 696) were chromosomally abnormal. Women with advanced maternal age (AMA) were 1.3 times more likely to have chromosomal errors (95% CI 1.1-1.4) than younger subjects (<38 years old). Morphology predicted PGD results in the AMA group (n = 553), but not in younger women. Fragmentation predicted euploidy in both the younger and the AMA group, but cell number did not. CONCLUSION(S): Day-3 embryo morphology selects for euploidy among AMA subjects but not among younger women who may have other factors responsible for embryo dysmorphism. However, cellular fragmentation is a sensitive proxy for selecting chromosomally normal embryos in both age groups. It is unclear that PGD-aneuploidy screening is a better tool for selecting which embryos to transfer than the standard approach of using day-3 embryo features, particularly among older women, a group for whom this technology is targeted.
Assuntos
Aneuploidia , Blastocisto/patologia , Transferência Embrionária , Fertilização in vitro , Testes Genéticos , Hibridização in Situ Fluorescente , Idade Materna , Diagnóstico Pré-Implantação/métodos , Adulto , Técnicas de Cultura Embrionária , Feminino , Humanos , Valor Preditivo dos Testes , Gravidez , Estudos Retrospectivos , Fatores de TempoRESUMO
OBJECTIVE: The purpose of this study was to evaluate ethnic differences in low birth weight and gestational age-dependent birth weight. STUDY DESIGN: A retrospective cohort study of 47,669 newborn infants was conducted with the use of the perinatal database of the Memorial Health Care System. Logistic regression was used to estimate the odds ratio for low birth weight by ethnic group, which took into account gestational age at delivery. Multiple linear regression models were then developed to predict ethnic differences in birth weight by gestational age. RESULTS: When compared with white women, the adjusted odds ratio for low birth weight in of Mexican origin women (1.16; 95% CI, 1.02-1.32) was substantially lower than that of African American women (2.21; 95% CI, 1.87-2.60). An analysis of birth weight by gestational age suggested that African American neonates were intrinsically smaller than Hispanic neonates (difference, 4.22%). CONCLUSION: At least some of the differences in low birth weight that are noted among ethnic minorities may be attributable to ethnic differences in birth weight by gestational age.
Assuntos
Hispânico ou Latino , Negro ou Afro-Americano , Peso ao Nascer , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Modelos Logísticos , Masculino , Gravidez , Estudos Retrospectivos , População BrancaRESUMO
Maternal peptides from the hypothalamic-pituitary-adrenal (HPA) axis rise during human pregnancy. The effects of circulating maternal adrenocorticotropin (ACTH) and beta-endorphin (BE) on human fetal behavior was determined in 135 women during their 32nd week of gestation. Fetal behavior was measured by assessing heart rate habituation to a series of repeated vibroacoustic stimuli. Individual differences in habituation were determined by computing the number of consecutive responses above the standard deviation during a control period. There was no significant relation between levels of ACTH, BE and the rate of fetal heart rate habituation. However, an index of HPA disregulation (uncoupling of ACTH and BE) was related significantly to fetal behavior. Fetal exposure to high levels of maternal BE relative to ACTH was associated with significantly lower rates of habituation. Results indicate that maternal stress and stress-related peptides influence fetal response patterns. It is possible that this influence persists over the life span.
Assuntos
Doenças do Sistema Endócrino/fisiopatologia , Feto/fisiologia , Sistema Hipotálamo-Hipofisário/fisiopatologia , Sistema Hipófise-Suprarrenal/fisiopatologia , Complicações na Gravidez , Complicações na Gravidez/fisiopatologia , Estimulação Acústica , Hormônio Adrenocorticotrópico/sangue , Adulto , Feminino , Habituação Psicofisiológica , Frequência Cardíaca Fetal , Humanos , Masculino , Gravidez , Complicações na Gravidez/sangue , Terceiro Trimestre da Gravidez , Caracteres Sexuais , Vibração , beta-Endorfina/sangueRESUMO
OBJECTIVES: Recent advances in the physiology of human pregnancy have implicated placental corticotropin-releasing hormone (CRH) as one of the primary endocrine mediators of parturition and possibly also of fetal development. The aim of this study was (1) to prospectively assess the relationship of maternal plasma concentrations of CRH in the early third trimester of gestation with two prematurity-related outcomes-spontaneous preterm birth (PTB), and small-for-gestational age birth (SGA), and (2) to determine whether the effects of CRH on each of these outcomes are independent from those of other established obstetric risk factors. STUDY DESIGN: In a sample of 232 women with a singleton, intrauterine pregnancy, maternal plasma was collected at 33 weeks' gestation and CRH concentrations were determined by radioimmunoassay. Each pregnancy was dated on the basis of last menstrual period and early ultrasonography. Parity, obstetric risk conditions for prematurity, mode of delivery, and birth outcomes were abstracted from the medical record. RESULTS: After adjusting for the effects of established obstetric risk factors, elevated CRH levels at 33 weeks' gestation were significantly associated with a 3.3-fold increase in the adjusted relative risk (RR) for spontaneous preterm birth and with a 3.6-fold increase in the adjusted relative risk for fetal growth restriction. Women who delivered postterm had significantly lower CRH levels in the early third trimester than those who delivered at term. When outcomes were stratified by gestational length and birth weight, the lowest CRH levels at 33 weeks' gestation were associated with the term non-SGA births, intermediate and approximately equal CRH levels were associated with the preterm non-SGA and term SGA births, and the highest CRH levels were associated with the preterm SGA births. CONCLUSION: For deliveries occurring after 33 weeks' gestation (the time of CRH sampling in this study), our findings support the notion that in humans placental CRH may play an impending, direct role in not only the physiology of parturition but also in processes related to fetal growth and maturation. Our results also support the notion that the timing of onset of parturition may be determined or influenced by events occurring earlier in gestation rather than those close to the time of actual onset of labor (ie, the notion of a "placental clock").