There is a critical need for reliable blood-based biomarkers associated with an increased risk of adverse perinatal outcomes in obese pregnant women.

Background: Twin reversed arterial perfusion sequence is a rare and potentially lethal condition affecting approximately 1% of monochorionic twin pregnancies and 1 in 35,000 pregnancies overall. An apparently normal (pump) twin perfuses its severely malformed cotwin with deoxygenated blood via retrograde flow in direct arterioarterial anastomoses between the umbilical arteries of each twin. Fetal intestinal volvulus is a rare condition usually manifesting after birth. We report a unique case of twin reversed arterial perfusion sequence in association with intestinal volvulus in the surviving pump twin. Case presentation: A 32-year-old Hispanic primigravida was referred to our clinic after a fetoscopy procedure of laser photocoagulation of anastomoses at 18 weeks of gestation. Follow up scans in the ex-pump twin revealed dilated bowel loops and a typical "whirlpool sign" at 26 weeks of gestation, and intrauterine intestinal volvulus was suspected. At 29 weeks of gestation, preterm premature rupture of membranes occurred, and an emergency cesarean section was performed. The newborn was diagnosed in the early neonatal period with intestinal perforation. The diagnosis was postnatally confirmed by surgery and histopathology. Conclusions: The type of fetal intervention and late gestational age of the procedure increase the risk of complications. This case alerts health providers to be vigilant in the follow-up of patients with complicated monochorionic pregnancies.

Introduction: We aim to synthesize the best available evidence on the accuracy of prenatal imaging for the diagnosis of congenital Zika syndrome due to maternal Zika virus (ZIKV) infection. Specifically, we explored the factors that may influence diagnosis accuracy, such as geographic area, endemicity of ZIKA, operator, gestational age, and type of reference standard used. Methods and analysis Study selection criteria: All types of observational studies were included, that examined pregnant women with ZIKV infection (positive real time polymerase chain reaction or immunoglobulin M (IgM) serological tests and plaque neutralization reduction test). The index tests included prenatal imaging studies (ultrasound and/or magnetic resonance imaging). The reference standard was defined as follows: 1) perinatal death, including stillbirth and neonatal death within the first 48 h of birth, 2) neonatal intensive care unit admission, and 3) composite adverse perinatal outcomes. Case reports will be excluded if they only included fewer than five case. Sources of information: PubMed, Scopus, ISI Web of Science, and Google Scholar will be search from inception to March 2021. Two researchers will independently screen study titles and abstracts for eligibility, followed by full-text assessment. Data extraction will include population, settings, timing, and use of the index test and reference standard used. We will assess the methodological quality of the included studies and a meta-analysis will be performed to estimate summary statistics. Bivariate and hierarchical summary receiver operating characteristic modeling will be used to evaluate the diagnostic performance. The quality of evidence will be assessed by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) metholody. Sources: This systematic review is funded by Secretaria Nacional de Ciencia y Tecnología-Panama. Ethics and dissemination: Ethical approval will not be necessary. Results will be published in a peer review scientific journal. Systematic review registration number in Prospero: CRD42020162914