Objectives To estimate procedure-related risks of miscarriage following amniocentesis and chorionic villus sampling (CVS) based on a systematic review of the literature and a meta-analysis.Methods A search of MEDLINE, EMBASE, CINHAL and The Cochrane Library (2000-2014)

Objective To develop a model for prediction of spontaneous delivery before 34 weeks based on maternal factors, placental perfusion and function at 11-13 weeks' gestation.Methods Two groups of studies: first, screening study of maternal characteristics, serum pregnancy-associated plasma protein-A (PAPP-A), free β-human chorionic gonadotrophin (β-hCG) and uterine artery pulsatility index (PI). Second, case-control studies of maternal serum or plasma concentration of placental growth factor (PlGF), placental protein 13 (PP13), a disintegrin and metalloprotease 12 (ADAM12), inhibin-A and activin-A. Regression analysis was used to develop a model for the prediction of spontaneous early delivery.Results Spontaneous early delivery occurred in 365 (1.1%) of the 34 025 pregnancies. A model based on maternal factors could detect 38.2% of the preterm deliveries in women with previous pregnancies at or beyond 16 weeks and 18.4% in those without, at a false positive rate (FPR) of 10%. In the preterm delivery group, compared with unaffected pregnancies there were no significant differences in the markers of placental perfusion or function, except for PAPP-A which was reduced.Conclusions Patient-specific risk of preterm delivery is provided by maternal factors and obstetric history. Placental perfusion and function at 11-13 weeks are not altered in pregnancies resulting in spontaneous early delivery.

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ObjectiveTo determine accurate estimates of risks of maternal and neonatal complications in pregnancies with fetal macrosomia by performing a systematic review of the literature and meta-analysis.Methods A search of MEDLINE, EMBASE, CINAHL and The Cochrane Library was performed to identify relevant studies reporting on maternal and/or neonatal complications in pregnancies with macrosomia having a birth weight (BW) > 4000 g and/or those with birth weight > 4500 g. Prospective and retrospective cohort and population-based studies that provided data regarding both cases and controls were included. Maternal outcomes assessed were emergency Cesarean section (CS), postpartum hemorrhage (PPH) and obstetric anal sphincter injury (OASIS). Neonatal outcomes assessed were shoulder dystocia, obstetric brachial plexus injury (OBPI) and birth fractures. Meta-analysis using a random-effects model was used to estimate weighted pooled estimates of summary statistics (odds ratio (OR) and 95% CI) for each complication, according to birth weight. Heterogeneity between studies was estimated using Cochran's Q, I 2 statistic and funnel plots.Results Seventeen studies reporting data on maternal and/or neonatal complications in pregnancy with macrosomia were included. In pregnancies with macrosomia having a BW > 4000 g, there was an increased risk of the maternal complications: emergency CS, PPH and OASIS, which had OR (95% CI) Complicaciones maternas y neonatales de la macrosomía fetal: revisión sistemática y metaanálisis RESUMEN Objetivo Determinar estimaciones precisas de los riesgos de complicaciones maternas y neonatales en embarazos con macrosomía fetal mediante la realización de una revisión sistemática de la literatura y un metaanálisis.Métodos Se realizó una búsqueda en MEDLINE, EMBASE, CINAHL y The Cochrane Library para identificar estudios relevantes que informaron sobre complicaciones maternas y/o neonatales en embarazos con macrosomía con un peso al nacer (PN) >4000 g y/o aquellos con un peso al nacer >4500 g. Se incluyeron estudios de cohortes prospectivos y retrospectivos y estudios basados en la población que proporcionaron datos con respecto a los casos y controles. Las medidas maternas de resultados evaluadas fueron la cesárea de urgencia (CU), la hemorragia posparto (HPP) y la lesión obstétrica del esfínter anal (LOEA). Los resultados neonatales evaluados fueron distocia de hombro, lesión obstétrica del plexo braquial (LOPB) y fracturas de nacimiento. Se utilizó un metaanálisis con un modelo de efectos aleatorios para estimar las estimaciones agrupadas ponderadas de los estadísticos resumen (razones de momios [RM] y IC del 95%) para cada complicación, según el peso al nacer. La heterogeneidad entre estudios se estimó mediante la prueba estadística Q de Cochran, la prueba estadística I 2 y gráficos de embudo.Resultados Se incluyeron 17 estudios que reportaron datos sobre las complicaciones maternas y/o neonatales en embarazos con macrosomía. En aquellos con un PN >4000 g, hubo un mayor riesgo de complicaciones maternas:...

PP13 is implicated in the pathogenesis of impaired placentation and subsequent development of early-PE but measurement of this placental product is unlikely to be useful in screening for the disease at 11-13 weeks.

CONTRIBUTION What are the novel findings of this work?This study has demonstrated the feasibility of introducing a two-stage screening program for diagnosis of vasa previa based on transvaginal sonography at 20-22 weeks' gestation for pregnancies with velamentous cord insertion at the routine 11-13-week scan and those with low-lying placenta at the routine 20-22-week scan. What are the clinical implications of this work?Accurate and effective prenatal diagnosis of pregnancies with vasa previa can be achieved by a two-stage screening protocol. Appropriate monitoring and delivery of such pregnancies can potentially reduce the overall rate of stillbirth by about 10%. ABSTRACTObjectives To examine the feasibility and effectiveness of a two-stage ultrasound screening strategy for detection of vasa previa and to estimate the potential impact of screening on prevention of stillbirth.Methods This was a retrospective study of data from prospective screening for vasa previa in singleton pregnancies, undertaken at the Fetal Medicine Unit at Medway Maritime Hospital, UK, between 2012 and 2018. Women booked for prenatal care and delivery in our hospital had routine ultrasound examinations at 11-13 and 20-22 weeks' gestation. Those with velamentous cord insertion at the inferior part of the placenta at the first-trimester scan and those with low-lying placenta at the second-trimester scan were classified as high-risk for vasa previa and had transvaginal sonography searching specifically for vasa previa, at the time of the 20-22-week scan. The management and outcome of cases with suspected vasa previa is described. We excluded cases of miscarriage or termination at < 24 weeks' gestation. ResultsThe study population of 26 830 singleton pregnancies included 21 (0.08%; 1 in 1278) with vasa previa. In all cases of vasa previa, the diagnosis was made at the 20-22-week scan and confirmed postnatally by gross and histological examination of the placenta. At the 11-13-week scan, cord insertion was classified as central in 25 071 (93.4%) cases, marginal in 1680 (6.3%), and velamentous in 79 (0.3%). In 16 (76.2%) of the 21 cases of vasa previa, cord insertion at the first-trimester scan was classified as velamentous at the inferior part of the placenta, in two cases (9.5%) as marginal and in three cases (14.3%) as central. The 21 cases of vasa previa were managed on an outpatient basis with serial scans for measurement of cervical length and elective Cesarean section at 34 weeks' gestation; all babies were liveborn but there was one neonatal death. In the study population, there were 83 stillbirths, none of which had evidence of vasa previa on postnatal examination. On the assumption that, if we had not diagnosed prenatally all 21 cases of vasa previa in our population, half of these cases would have resulted in stillbirth, then the potential impact of screening is prevention of 10.6% (10/94) of stillbirths.Conclusion A two-stage strategy of screening for vasa previa can be incorporated into routine clinical practice, and such a strategy...

Objective To estimate the risks of maternal and neonatal complications in pregnancies with macrosomia. Methods This was a retrospective cohort study conducted at a large maternity unit in the UK between January 2009 and December 2016. The incidence of maternal and neonatal complications in pregnancies with macrosomia, defined as birth weight (BW) > 4000 g, and in those with severe macrosomia, defined as BW > 4500 g, was compared with that in pregnancies with normal BW (2500-4000 g). Regression analysis was performed to determine odds ratios (ORs) for complications in macrosomic pregnancies compared to those with normal BW.

Objectives To estimate the procedure‐related risks of miscarriage following chorionic villus sampling (CVS) and amniocentesis in a large unselected screened population, and to determine whether these risks are consistent with those reported in systematic reviews and meta‐analyses. Methods This was a retrospective cohort study carried out on data obtained from a large fetal medicine unit in the UK between January 2009 and May 2018. We included all women with singleton pregnancy who booked for pregnancy care at our unit before 20 weeks' gestation, after excluding those with multiple pregnancy, major fetal defect, pregnancy termination and loss to follow‐up. We estimated the risk of miscarriage in women who underwent a CVS or amniocentesis as well as in those who did not have an invasive procedure. The procedure‐related risk of miscarriage was estimated as risk difference (95% CI) between the two groups. Univariate and multivariate regression analyses were used to derive odds ratios (95% CI) and determine which maternal and pregnancy characteristics provided a significant contribution in the prediction of miscarriage and whether CVS or amniocentesis provided a significant independent contribution. Results During the study period, 45 120 singleton pregnancies were booked for pregnancy care at our hospital, of which 1546 had an invasive procedure. We excluded 1429 (3.2%) pregnancies due to fetal defects, termination of pregnancy or missing outcomes. Of the 43 691 pregnancies included in the study population, 861 underwent CVS and 375 amniocentesis. In pregnancies that underwent CVS, the risk of miscarriage was 1.5% (13/861), compared with 1.2% (476/39 152) in pregnancies that had first‐trimester combined screening and did not have an invasive procedure (P = 0.437). In pregnancies that underwent an amniocentesis, the risk of miscarriage was 0.8% (3/375), compared with 1.2% (491/42 463) in those that did not undergo an invasive procedure (P = 0.520). Univariate and multivariate regression analysis demonstrated that there was no significant contribution in the prediction of the risk of miscarriage from CVS (P = 0.399 and P = 0.592, respectively) or amniocentesis (P = 0.543 and P = 0.550, respectively). The risk of procedure‐related loss attributed to CVS was 0.29% (95% CI, −0.53 to 1.12%) and that following amniocentesis was −0.36% (95% CI, −1.26 to 0.55%), which was not significantly different from the risk in women who did not have any procedure. Conclusions The procedure‐related risks of miscarriage following CVS and amniocentesis in our study are considerably lower than those currently quoted and are consistent with the estimates of such risks reported by systematic reviews and meta‐analyses. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.