Amnio-exchange for gastroschisis does not help, and may even harm

This is a mini commentary on D Luton et al., pp. 1233–1241 in this issue. To view this article visit https://doi.org/10.1111/1471-0528.15804

Synthesis, Structural Studies and Aerosol-Assisted Chemical Vapour Deposition of Precursors towards Zinc Chalcogenides

This work is concerned with the design, synthesis, isolation and subsequent aerosolassisted chemical vapour deposition (AACVD) of precursors towards the zinc chalcogenide materials: zinc oxide (ZnO) and zinc oxysulfide (Zn(O,S)). Throughout this thesis, emphasis is placed on elucidating the relationship between the molecular structure of the precursor and the functional properties of the resultant material. Chapter 3 explores this relationship for a series of six precursors bearing !-ketoimine and !-aminoenoate ligands towards ZnO thin films via AACVD. The deposition of ZnO thin films has been an area of interest in the materials chemistry community due to its importance as a semiconductor in optoelectronic devices. Thin film quality is of paramount importance in these applications and as such, precursor design remains a research priority. Chapter 4 describes the synthesis and characterisation of a family of heteroleptic zinc thioureide complexes with a view to application as single source precursors for the AACVD of Zn(O,S), as well as being interesting synthetic targets in their own right. The scarcity of reports of the AACVD of Zn(O,S) via a single source precursor in the literature to date may not just be due to the fact that this is an emerging material, but also due to the lack of a suitable precursor. Chapter 5 explores the combinatorial analysis of Zn(O,S) films in order to better understand the effects of intermediate compositions on the optoelectronic properties of the material. The analysis of films from both commercially available precursors and a novel precursor is undertaken and in the latter case, emphasis is placed on the molecular properties of the precursor and the effect this has on the deposited Zn(O,S) films

Focus on Prenatal Detection of Micrognathia

Fetal micrognathia involves abnormal or arrested development of the fetal mandible. Till recently, the prenatal diagnosis was subjective, based on the evaluation of the fetal profile and assessment of the relationship between the maxilla and the mandible. Recently objective sonographic methods have been utilized for diagnosing micrognathia such as the inferior facial angle, the jaw index, the frontal nasomental angle, the mandible width/maxilla width ratio and the mandibular length. Another useful sonographic sign, the mandibular gap in the retronasal triangle view, increases the accuracy of the diagnosis early in the first trimester. 3D sonographic views can add to the diagnosis and prenatal MRI is a useful adjunct to ultrasound in cases of limited acoustic window, maternal obesity, oligohydramnios and anterior spine position. The identification of micrognathia should prompt karyotyping and sonographic investigation for other abnormalities. The outcome of fetuses with this seemingly isolated finding is more guarded than one would intuitively believe, and the parents should be counseled accordingly. Postnatal complications including mild to severe upper airway obstruction leading to respiratory distress, feeding difficulties and mild to severe long-term developmental delay are common. One should be careful in pronouncing a fetus having ‘micrognathia’, especially on subjective evaluation, as this term implies that the fetus is abnormal with presence of significant pathology. There is no ‘gold standard’ for a definitive diagnosis of micrognathia on post-natal evaluation. Using a combination of objective sonographic markers as well as follow-up ultrasound assessments can significantly reduce the risk of a false diagnosis. Follow-up scans should be arranged, and neonatal service should be alerted in cases of ongoing pregnancies

Prenatal Diagnosis of WAGR Syndrome.

Wilm's tumour, aniridia, genitourinary abnormalities, and mental retardation (WAGR) syndrome is a rare genetic disorder with an estimated prevalence of 1 in 500,000 to 1 million. It is a contiguous gene syndrome due to deletion at chromosome 11p13 in a region containing WT1 and PAX6 genes. Children with WAGR syndrome mostly present in the newborn/infancy period with sporadic aniridia. The genotypic defects in WAGR syndrome have been well established. However, antenatal ultrasonographic presentation of this syndrome has never been reported. Prenatal diagnosis of this condition is possible in some cases with careful ultrasound examination of classical and nonclassical manifestations of this syndrome. The key point for this rare diagnosis was the decision to perform chromosomal microarray analysis after antenatal diagnosis of absent corpus callosum and absent cavum septum pellucidum, as this finding mandates search for potentially associated genetic disorders. We report a case of WAGR syndrome diagnosed prenatally at 29-week gestation. The diagnosis of the anomaly was based on two- and three-dimensional ultrasound as well as fetal MRI scan and microarray analysis. The ultrasonographic findings included borderline ventriculomegaly, absent corpus callosum, and absent cavum septum pellucidum. Cytogenetic results from the amniotic fluid confirmed WAGR syndrome. Parental karyotype was normal, with no evidence of copy number change, deletion, or rearrangement of this region of chromosome 11

Routine screening for placenta accreta spectrum.

Screening for clinically significant placenta accreta spectrum (PAS) is possible with a high degree of accuracy (both sensitivity and specificity >90-95%). The group of women to focus on are those with placenta previa and one or more prior Cesarean deliveries. Screening for PAS not associated with placenta previa is not as productive, and several false negatives have been described. The results of the screening program indicate that women have a low or high probability of PAS. Screen-positive women or those with uncertain ultrasound features should be referred to a center of excellence. Those confirmed to have a high probability of PAS should electively be delivered at such centers

Morbid adherence of the placenta: lack of specificity should remind us that ultrasound is a screening tool.

Excellent performance has been reported with prenatal diagnosis of abnormal placental invasion using ultrasound. We describe a case which illustrates the validity of ultrasound features of abnormally invasive placentation in women without previous caesarean delivery. CASE: Ms. CB, a 27 year-old G3 P1+1 was seen in her pregnancy at 36 weeks of gestation. Her first pregnancy was uncomplicated and she gave vaginal birth to a normally grown baby at term. Before the current pregnancy, she suffered a miscarriage in the first trimester, and underwent surgical evacuation. She suffered prolonged vaginal blood loss for which she was investigated, and a diagnosis of A-V malformation (AVM) was made on the basis of the ultrasound findings (Figure 1). She conceived spontaneously before intervention

The Association Between Hypertension in Pregnancy and Preterm Birth with Fetal Growth Restriction in Singleton and Twin Pregnancy: Use of Twin Versus Singleton Charts.

OBJECTIVE: To compare the rates of fetal growth restriction (FGR) in singleton and twin pregnancies using singleton and twin-specific birthweight standards. METHODS: The study included liveborn twin and singleton pregnancies between January 2000 and January 2019. Hypertensive disorders of pregnancy (HDP) included gestational hypertension and pre-eclampsia. The study outcomes were FGR or small-for-gestational-age (SGA) at birth as assessed using singleton and twin reference charts. RESULTS: The analysis included 1473 twin and 62,432 singleton pregnancies. In singleton pregnancies the risk of PTB <34 weeks without HDP (OR 2.82, p < 0.001), delivery ≥34 weeks with HDP (OR 2.38, p < 0.001), and PTB <34 weeks with HDP (OR 13.65, p < 0.001) were significantly higher in the pregnancies complicated by FGR compared to those without. When selective fetal growth restriction (sFGR) was assessed using the singleton standard, the risk of PTB <34 weeks without HDP (OR 1.03, p = 0.872), delivery ≥34 weeks with HDP (OR 1.36, p = 0.160) were similar in the pregnancies complicated by sFGR compared to those without, while the risk of PTB <34 weeks with HDP (OR 2.41, p = 0.025) was significantly higher in the pregnancies complicated by sFGR compared to those without. When sFGR was assessed using the twin-specific chart, the risk of PTB <34 weeks without HDP (OR 3.55, p < 0.001), delivery ≥34 weeks with HDP (OR 3.17, p = 0.004), and PTB <34 weeks with HDP (OR 5.69, p < 0.001) were significantly higher in the pregnancies complicated by sFGR compared to those without. The stronger and more consistent association persisted in the subgroup analyses according to chorionicity. The strength of association in dichorionic twin pregnancies resembles that of the singletons more closely and consistently when the FGR was diagnosed using the twin-specific charts. CONCLUSION: FGR in twin pregnancies has a stronger and more consistent association with HDP and PTB when using twin-specific rather than singleton charts. This study provides further evidence supporting the use of twin-specific charts when assessing fetal growth in twin pregnancies

Peyer's Patches Are Precocious to the Appendix in Human Development

PP are first visible at ∼15.5 wk gestation after which there is a rapid spurt in the development and maturation of lymphoid follicles so that at any given point of time new foci of PP development are continuously formed at a rapid rate. Addition of rows of follicles results in the formation of a PP. Immature PP of younger fetuses have a spongy structure in contrast with the compact lymphoid follicles of mature PP of older fetuses. Immunocytochemical studies reveal that there is a subtle gradation in the expression of lymphocyte surface markers with increasing fetal age. Expression of antigenic markers occurs in an ordered sequence viz. HLA – DR, CD19 (B cell population), CD9 (pre-B cells), CD3 T lymphocytes, CD4 helper / inducer lymphocytes, the CD8 suppressor / cytotoxic cells and lastly, the CD57 Natural Killer cells. The antigens are expressed first on lymphocytes of PP and thereafter in those of the appendix. Our findings clearly demonstrate that the ∼5 wk fetal period from 17.5 wk to 22 wk represents a major growth phase in the development of surface markers of lymphocytes in the mucosal immune system of the gut

Are Twin Pregnancies Complicated by Weight Discordance or Fetal Growth Restriction at Higher Risk of Preeclampsia?

Studies have reported controversial findings on the association between fetal growth restriction (FGR) or intertwin weight discordance and the risk of hypertensive disorders of pregnancy (HDP) in twin pregnancies. The aim of this study was to investigate the association between twin growth disorders and HDP. Twin pregnancies resulting in two live births at St George's Hospital between 2000 and 2019 were included. FGR or small-for-gestational-age (SGA) at birth was assessed using singleton and twin reference charts. Intertwin discordance [(large birthweight - small birthweight)/(large birthweight) × 100%)] was calculated. Logistic regression models were performed. SGA (aOR 2.34, 95% CI 1.60-3.44, p < 0.001), intertwin discordance ≥25% (aOR 2.10, 95% CI 1.26-3.49, p = 0.004) and their co-existence (aOR 2.03, 95% CI 1.16-3.54, p = 0.013) were significantly associated with HDP. After adjusting for the known maternal risk factors of HDP and the intertwin discordance, SGA (using the twin charts) was the strongest independent risk factor associated with HDP (aOR 2.12, 95% CI 1.40-3.22, p < 0.001) and preeclampsia (aOR 2.34, 95% CI 1.45-3.76, p < 0.001). This study highlights that the presence of at least one SGA twin is significantly associated with HDP during pregnancy. Therefore, maternal blood pressure should be closely monitored in twin pregnancies complicated by SGA with or without intertwin discordance