The January issue of Ultrasound in Obstetrics & Gynecology is completely free to access and includes a randomized controlled trial on elective delivery at 34 weeks vs routine obstetric care in fetal gastroschisis, a study on the outcome of twin pregnancy with two live fetuses at 11–13 weeks, a comparative analysis of the of the 2-year outcomes in the GRIT and TRUFFLE trials, a study on the ratio of fetal choroid plexus to head size as a first-trimester sonographic marker of open spina bifida, a study comparing brain microstructure after prenatal spina bifida repair by either laparotopy-assisted fetoscopic or open approach, and an analysis of copy-number variations associated with early pregnancy loss.
Elective delivery at 34 weeks vs routine obstetric care in fetal gastroschisis: randomized controlled trial
Despite a decrease in mortality associated with fetal gastroschisis over the past few decades, the associated morbidity remains a matter of concern. There is conflicting evidence regarding the benefit of decreasing intrauterine intestinal exposure to amniotic fluid by planning early delivery in these pregnancies. In a randomized controlled trial, Shamshirsaz et al. evaluated whether elective preterm delivery at 34 weeks is of postnatal benefit to infants with isolated gastroschisis compared with routine obstetric care. Early delivery was found to have no benefit when postnatal gastroschisis management is similar to that used in routine care. Rather, early delivery was found to be associated with a higher rate of neonatal late-onset sepsis, suggesting that early delivery is detrimental to infants with gastroschisis. View the accompanying video abstract:
Outcome of twin pregnancy with two live fetuses at 11–13 weeks’ gestation
While monochorionic diamniotic (MCDA) twin pregnancies, compared to dichorionic (DC) twins, are known to have a higher rate of fetal loss, there are large discrepancies in the reported rates. Litwinska et al. assessed pregnancy outcome in 6225 DC, MCDA and monochorionic monoamniotic (MCMA) twin pregnancies with two live fetuses at 11–13 weeks. The rates of fetal loss at <24 weeks, perinatal death at ≥24 weeks and preterm birth were found to be higher in MCDA and more so in MCMA twins than in DC twins. In MCDA twins, the rate of fetal loss may have been reduced by endoscopic laser surgery in those that developed early twin–twin transfusion syndrome and/or selective fetal growth restriction.
Comparative analysis of 2-year outcomes in GRIT and TRUFFLE trials
Treatment of the underlying cause of early-onset fetal growth restriction (FGR) is impossible and the challenge therefore lies in optimizing the timing of delivery. To date, only two large randomized trials have evaluated timing of delivery in these pregnancies: GRIT and TRUFFLE. Ganzevoort et al. explored the effect on perinatal outcome of the different fetal monitoring strategies for early-onset FGR in GRIT and TRUFFLE. The rate of survival without impairment at 2 years was highest in pregnancies monitored using a combination of computerized cardiotocography and ductus venosus Doppler assessment, supporting the hypothesis that this is the optimal method for fetal monitoring in pregnancies complicated by early-onset FGR (view the accompanying Journal Club slides).
Ratio of fetal choroid plexus to head size: simple sonographic marker of open spina bifida at 11–13 weeks’ gestation
While there has been growing interest in the use of indirect sonographic markers of open spina bifida in early gestation, only few data have been published on ultrasound markers in the axial plane of the head. Chaoui et al. assessed increased ratio of choroid plexus to head size as a first-trimester marker of open spina bifida. It was found that, at 11–13 weeks, the majority of fetuses with open spina bifida have reduced fluid in the lateral ventricles such that the choroid plexuses fill the head, giving the appearance of a ‘dried brain’. The sign is easily visualized during routine first-trimester ultrasound examination while measuring biparietal diameter, and can be quantified by comparing the size of the choroid plexuses to the head size.
Comparison of brain microstructure after prenatal spina bifida repair by either laparotomy-assisted fetoscopic or open approach
Fetoscopic repair of myelomeningocele (MMC) has been proposed to decrease maternal obstetric risks compared with open repair, while preserving the fetal benefits. However, there are concerns about the safety of utilization of CO2 for uterine insufflation. Sanz Cortes et al. compared prenatal and postnatal brain microstructure assessed by diffusion-weighted imaging between infants that underwent fetoscopic MMC repair and those that had open-hysterotomy repair. It was found that fetoscopic MMC repair has no detectable effect on brain microstructure when compared to babies repaired using an open-hysterotomy technique. CO2 insufflation of the uterine cavity during fetoscopy therefore does not seem to have any isolated deleterious effects on fetal brain microstructure.
Systematic analysis of copy-number variations associated with early pregnancy loss
Specific information based on large cohorts regarding the association between submicroscopic copy-number variations (CNVs) and miscarriage is limited. Wang et al. analyzed chromosomal abnormalities in more than 5000 fresh miscarriage specimens. Three submicroscopic CNVs were found to be associated with miscarriage, 44 critical regions of large CNVs were observed and 309 genes were identified as potential miscarriage candidate genes. The findings demonstrate the importance of CNVs in the etiology of miscarriage and highlight the importance of ongoing analysis of CNVs in the study of miscarriage.
Coming up in the next issue…
- A study on the value of routine ultrasound examination at 35–37 weeks’ gestation in diagnosis of non-cephalic presentation. Preview the Accepted Article.
- A subgroup analysis of a randomized controlled trial on the effect of sildenafil on maternal hemodynamics in pregnancies complicated by severe early-onset fetal growth restriction. Preview the Accepted Article.
- A follow-up study on the performance of non-invasive cell-free DNA testing in 31515 singleton pregnancies. Preview the Accepted Article.