One vs 2 courses of antenatal corticosteroids in pregnancies at risk of preterm birth: a secondary analysis of the MACS trial.

BACKGROUND: Birth is unpredictable and many patients who receive antenatal corticosteroids for preterm birth remain pregnant. Some professional societies recommend rescue antenatal corticosteroids for those who remain pregnant ≥14 days following the initial course. OBJECTIVE: This study aimed to explore a single vs a second course of antenatal corticosteroids in terms of severe neonatal morbidity and mortality. STUDY DESIGN: This is a secondary analysis of the Multiple Courses of Antenatal Corticosteroids for Preterm Birth (MACS) trial. The MACS study was a randomized clinical trial conducted in 80 centers in 20 different countries from 2001 to 2006. Participants who received only 1 course of intervention (ie, either a second course of antenatal corticosteroids or placebo) were included in this study. The primary outcome was a composite of stillbirth, neonatal mortality in the first 28 days of life or before discharge, severe respiratory distress syndrome, bronchopulmonary dysplasia, intraventricular hemorrhage stage III and IV, periventricular leukomalacia, and necrotizing enterocolitis. Two subgroup analyses were planned to address the effect of a second course of antenatal corticosteroids on infants born before 32 weeks or within 7 days from the intervention. Moreover, a sensitivity analysis was performed to assess the effect of intervention on singleton pregnancies. Baseline characteristics were compared between the groups using chi-square and Student t tests. Multivariable regression analysis was performed to adjust for confounding variables. RESULTS: There were 385 and 365 participants included in the antenatal corticosteroid and placebo groups, respectively. The composite primary outcome occurred in 24% and 20% of participants in the antenatal corticosteroid and placebo groups, respectively (adjusted odds ratio, 1.09; 95% confidence interval, 0.76-1.57). Moreover, severe respiratory distress syndrome rate was similar between the 2 groups (adjusted odds ratio, 0.98; 95% confidence interval, 0.65-1.48). Newborns exposed to antenatal corticosteroids were more likely to be small for gestational age (14.9% vs 10.6%; adjusted odds ratio, 1.63; 95% confidence interval, 1.07-2.47). These findings remained true among singleton pregnancies for the primary composite outcome and birthweight <10th percentile (adjusted odds ratio, 1.29 [0.82-2.01]; and adjusted odds ratio, 1.74 [1.06-2.87]; respectively). Subgroup analyses of infants born before 32 weeks or within 7 days from the intervention did not show any benefits in terms of the composite primary outcome with antenatal corticosteroids vs placebo (50.5% vs 41.8% [adjusted odds ratio, 1.16; 95% confidence interval, 0.78-1.72]; and 42.3% vs 37.1% [adjusted odds ratio, 1.02; 95% confidence interval, 0.67-1.57]; respectively). CONCLUSION: Neonatal mortality and severe morbidities, including severe respiratory distress syndrome, were not improved by a second course of antenatal corticosteroids. Policy makers need to be thoughtful when recommending a second course of antenatal corticosteroids and consider whether not only short-term but also long-term benefits can be gained from such administration.

Hernia diafragmática congénita / Congenital diaphragmatic hernia

The congenital diaphragmatic hernia (CDH) is a congenital defect of the formation and /or closure of the diaphragm that permits the herniation of abdominal contents into the thorax. It occurs when the diaphragmatic muscle fails to close during the prenatal development, and the contain of the abdomen migrate into the chest through this hole. When the abdominal organs are in the chest, there is limited room for the lungs to grow. This prevents the lungs for developing normally, resulting in pulmonary hypoplasia (or underdeveloped lungs). This can cause reduced blood flow to the lungs and pulmonary hypertension, as well as gastrointestinal reflux, feeding disorders and developmental delays. CDH can occur on the left side, right side or, very rarely, on both sides, and it can be life-threatening. The etiology is usually unknown. The incidence of CDH may be as high as 1 in 2000 to 1 in 5000 newborns alive. The sex relationship male/female is 1:1.8. Because of associated persistent pulmonary hypertension of the newborn and pulmonary hypoplasia, medical therapy in patients with CDH is directed toward optimizing oxygenation while avoiding definitive therapy. No time for repair of CDH is ideal, but it is suggested that the opportunity is 24-48 hours after birth to achieve pulmonary development. The key to survival lies in prompt diagnosis and treatment. Over the past two decades antenatal diagnosis rates have increased the knowledge of the pathophysiology of CDH and has become better understand with advances in clinical care including prenatal surgery, with a reported mortality of almost 35 % in live-born patients and a higher mortality when in utero deaths are conected. All these considerations are described in the article, with special reference to pre and post-natal treatment, complications management, diagnosis and prognosis

Síndrome de Banda Amniótica / Amniotic Band Syndrome

Amniotic band sequence or syndrome, is the term applied to a wide range of congenital anomalies, as a group of congenital birth defects caused by entrapment of fetal parts (usually a limb or digits) in fibrous amniotic bands while in utero. Before the baby was born, the body parts shows signs of arm, fingers, etc, that were caught and estrangled. Amniotic band syndrome can cause a number of different birth defects depending on which body part(s) is affected. Amniotic band sequence (ABS) is a rare condition caused by strands of the amniotic sac that separate and entrangle digits, limbs or other parts of the fetus. This constriction can cause a variety of problems depending on where the strands are located and how trightly they are wrapped. ABS can cause a broad spectrum of anomalies ranging from simple band constrictions to major craniofacialand visceral defects. This causes deformations, malformation and disruption, that results in incapacity or death. The aims of the present report, were to present a review of the literature concerning with this pathology, describing the clinical characteristics, etiology, diagnosis and prognosis, in order to improve the efficacy of the prenatal management

Elastografía: una nueva herramienta en obstetricia / ELASTOGRAPHY: A NEW TOOL IN OBSTETRICS

Elastography is a new method which is innovating its use in obstetrics. Elastography has been employed in different fields as a complement of the bidimensional sonography and has been widely studied. However, guidelines for the employement of elastography of the uterine cervix are not available at present. The limitations consist in that there is not a reference of the normel tissue, and of the pathological elasticity of the preterm labor delivery, and besides it is necessary in some types of elastographies an external force which is dependant operator for which the performance of elastographies with cut waves or quantitatives seems to be the most promising method for the evaluation of the elasticity of the cervix. The present utility, current status and future challenges are well docummented in the article. The diagnostic accuracy of cervical elastography in predicting labor induction success is reviewed. The wave elastography of placenta for in vivo quantation of placental elasticity is also considered.

Ultrasonografía tridimensional en el diagnóstico precoz de malformaciones fetales / Three dimensional ultrasonography in the early diagnosis of fetal anomalies

Observación de características morfológicas fetales por examen ultrasonográfico tridimensional en pacientes embarazadas con ecografía bidimensional anormal actual o con antecedentes de malformación congénita