Mechanical Ventilation in Pregnancy Due to COVID-19: A Cohort of Three Cases

We describe our experience with three pregnant women with novel coronavirus disease 2019 (COVID-19) who required mechanical ventilation. Recent data suggest a mortality of 88% in nonpregnant patients with COVID-19 who require intubation and mechanical ventilation. The three women we report were intubated and mechanically ventilated during pregnancy due to respiratory failure and pneumonia resulting from COVID-19. After several days of ventilation, all three were successfully weaned off mechanical ventilation and extubated, and are continuing their pregnancies with no demonstrable adverse effects. Our experience suggests that the mortality in pregnant women with COVID-19 requiring mechanical ventilation is not necessarily as high as in nonpregnant patients with COVID-19. KEY POINTS: · Coronavirus disease 2019 (COVID-19) is now a pandemic.. · COVID-19 may cause pneumonia or respiratory failure in pregnant women.. · Approximately 5% of women with COVID-19 will develop severe or critical disease.. · Mechanical ventilation in pregnant women may not necessarily result in high mortality rates..

Physiologic proteinuria in labor and postpartum: The results of the postpartum proteinuria trial (PoPPy)

The urine protein to creatinine ratio (PC) is a sensitive and specific means of diagnosing preeclampsia in the antepartum period, but the 0.3 g protein per gram of creatinine threshold may be non-specific postpartum due to physiologic proteinuria after delivery. The objective of this study was to examine the reliability of PC in labor and postpartum and to determine if PC is affected by mode of delivery. This is the first study of its kind to examine physiologic proteinuria by catheterized PC in individual patients before and after delivery. This single-center prospective cohort study included two groups: term uncomplicated nulliparous patients in labor with epidural analgesia and patients for scheduled repeat cesarean deliveries. Patients with hypertension, antepartum proteinuria, renal disease, gross hematuria, or evidence of infection were excluded. Catheterized pre- and post-delivery urine PC were compared using paired t-tests. 27 and 40 patients were included in the vaginal and cesarean delivery groups, respectively. 52% of the vaginal delivery and 58% of the cesarean delivery groups were positive for proteinuria at the 0.3 g protein per g creatinine threshold. Pre- and post-delivery specimens were significantly different in the vaginal (mean difference 0.28, p = 0.05) and cesarean (mean difference 0.25, p < 0.01) delivery groups. The conclusions reached included the finding that PC measurements are unreliable in the immediate postpartum period regardless of mode of delivery, and utilizing the 0.3 threshold to diagnose preeclampsia in close proximity to delivery would contribute to increased false positive tests.

Vasa Previa: Prenatal Diagnosis and Outcomes: Thirty-five Cases From a Single Maternal-Fetal Medicine Practice

OBJECTIVES

To assess the accuracy and effectiveness of routine screening for vasa previa, to describe our experience, and to assess factors that contribute to missed cases of vasa previa.

METHODS

A retrospective descriptive study of all cases of vasa previa from a single maternal-fetal medicine service between 2009 and 2017 was performed. Ultrasound findings and obstetric and neonatal outcomes were reviewed and analyzed.

RESULTS

Thirty-five cases of vasa previa were identified. Most cases (33 of 35 [94.3%]) were diagnosed antenatally. All 33 cases that followed our screening protocol were diagnosed antenatally and had favorable outcomes. Two cases that did not follow our protocol were not diagnosed antenatally and were delivered emergently. The mean gestational age ± SD at delivery of antenatally diagnosed cases was 34.9 ± 1.69 weeks. All neonates survived.

CONCLUSIONS

Routine ultrasound screening for vasa previa using American Institute of Ultrasound in Medicine criteria will almost universally lead to good outcomes and prevent perinatal mortality.

Pesticide concentrations in maternal and umbilical cord sera and their relation to birth outcomes in a population of pregnant women and newborns in New Jersey

We evaluated in utero exposures to pesticides by measuring maternal and cord serum biomarkers in a New Jersey cohort of pregnant women and the birth outcomes of their neonates. The study was based on 150 women that underwent an elective cesarean delivery at term in a hospital in central New Jersey. We evaluated the following pesticide compounds in both maternal and umbilical cord sera: chlorpyrifos, diazinon, carbofuran, chlorothalonil, dacthal, metolachlor, trifluralin and diethyl-m-toluamide (DEET). Of these compounds, chlorpyrifos, carbofuran, chlorothalonil, trifluralin, metolachlor and DEET were the pesticides most frequently detected in the serum samples. We found high (> or =75th percentile) metolachlor concentrations in cord blood that were related to birth weight (3605 g in upper quartile vs 3399 g; p=0.05). We also observed an increase in abdominal circumference with increasing cord dichloran concentrations (p=0.031). These observations suggest that in utero exposures to certain pesticides may alter birth outcomes.

Perinatal exposure to perchlorate. thiocyanate, and nitrate in New Jersey mothers and newborns

Perchlorate is a commonly occurring environmental toxicant that may be transported across the placental barrier by the sodium-iodide symporter (NIS), possibly resulting in both increased perchlorate exposure and decreased iodide uptake by the fetus. Therefore, we measured levels of three physiologically relevant NIS-inhibitors (perchlorate, nitrate, and thiocyanate) and iodide in maternal and fetal fluids collected during cesarean-section surgeries on 150 U.S. women. Geometric means of perchlorate, thiocyanate, and nitrate levels in maternal urine (2.90, 947, and 47900 microg/L, respectively) were similar to previously published results, while urinary iodide levels (1420 microg/L) were significantly higher (p < 0.0001), likely because of prevalent prenatal vitamin use in the study population (74%). Thiocyanate levels were higher in the maternal serum, cord serum, and amniotic fluid of smokers compared to women with environmental tobacco smoke exposure and nonsmokers (p-values of 0.0006, 0.0011, and 0.0026, respectively). Perchlorate was detected in most samples: urine (100%), maternal serum (94%), cord serum (67%), and amniotic fluid (97%). Maternal urinary perchlorate levels were positively correlated with perchlorate levels in amniotic fluid (r = 0.57), indicating that maternal urine perchlorate is an effective biomarker of fetal perchlorate exposure. Maternal serum perchlorate was generally higher than cord serum perchlorate (median ratio 2.4:1 for paired samples), and maternal urine perchlorate was always higher than fetal amniotic fluid perchlorate levels (mean ratio 22:1); conversely, iodide levels were typically higher in fetal fluids compared to maternal fluids. We found no evidence of either disproportionate perchlorate accumulation or lack of iodide in the fetal compartment. In this panel of healthy infants, we found no association between cord blood levels of these anions and newborn weight length, and head circumference.

Phthalates Biomarker Identification and Exposure Estimates in a Population of Pregnant Women

Phthalates are known reproductive and developmental toxicants in experimental animals. However, in humans, there are few data on the exposure of pregnant women that can be used to assess the potential developmental exposure experienced by the fetus. We measured several phthalate metabolites in maternal urine, maternal serum, and cord serum samples collected at the time of delivery from 150 pregnant women from central New Jersey. The urinary concentrations of most metabolites were comparable to or less than among the U.S. general population, except for mono(2-ethylhexyl) phthalate (MEHP), mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono(2-ethyl-5-oxohexyl) phthalate (MEOHP), three metabolites of di(2-ethylhexyl) phthalate (DEHP). The median urinary concentrations of MEHHP (109 mug/l) and MEOHP (95.1 mug/l) were more than 5 times their population-based concentrations, whereas the median urinary concentration of MEHP was more than 20 times higher. High concentration of MEHP may indicate a recent exposure to the parent chemical DEHP in the hospital shortly before the collection of the samples. Calculation of daily intakes using the urinary biomarker data reveals that none of the pregnant women tested had integrated exposures to DEHP greater than the Agency for Toxic Substances and Disease Registry's minimal risk levels (MRLs chronic 60, intermediate 100 mug/kg/day). No abnormal birth outcomes (e .g., birth weight, Apgar Score, and gestational age) were noted in those newborns whose mothers had relatively greater exposure to DEHP during the perinatal period than others in this study. Significantly greater concentrations and detection frequencies in maternal urine than in maternal serum and cord serum suggest that the urinary concentrations of the phthalate metabolites may be more reliable biomarkers of exposure than their concentrations in other biological specimens.

Vasa Previa: The Impact of Prenatal Diagnosis on Outcomes

OBJECTIVE

To evaluate outcomes and predictors of neonatal survival in pregnancies complicated by vasa previa and to compare outcomes in prenatally diagnosed cases of vasa previa with those not diagnosed prenatally.

METHODS

We performed a multicenter study of 155 pregnancies complicated by vasa previa. Cases were obtained from the Vasa Previa Foundation and 6 large hospitals. Comparisons were made between groups based on prenatal diagnosis status and neonatal survival.

RESULTS

The overall perinatal mortality was 36% (55 of 155). In 61 cases (39%), vasa previa was diagnosed prenatally; 59 of 61 (97%) infants from these pregnancies survived compared with 41 of 94 (44%) in cases not diagnosed prenatally (P <.001). Median 1- and 5-minute Apgar scores in cases diagnosed prenatally were 8 and 9, respectively, compared with 1 and 4 among survivors in cases not diagnosed prenatally (P <.001). More than half (24 of 41) of surviving neonates born to women without prenatal diagnosis required blood transfusions compared with 2 of 59 diagnosed prenatally (P <.001). Multivariable logistic regression analysis showed that the only significant predictors of neonatal survival were prenatal diagnosis (P <.001) and gestational age at delivery (P =.01).

CONCLUSIONS

Good outcomes with vasa previa depend primarily on prenatal diagnosis and cesarean delivery at 35 weeks of gestation or earlier should rupture of membranes, labor, or significant bleeding occur.

Fetal transcerebellar diameter nomogram in singleton gestations with special emphasis in the third trimester: A comparison with previously published nomograms

OBJECTIVE

This study was undertaken to construct an institution-specific transverse cerebellar (transcerebellar) diameter nomogram with special emphasis in the third trimester and to compare its ability to predict gestational age with previously published nomograms.

STUDY DESIGN

A cross-sectional nomogram was constructed using transcerebellar diameter measurements in 24,026 well-dated singleton fetuses by using linear regression models. Third-trimester measurements from 2,010 fetuses were included. The performance of previously established transcerebellar diameter nomograms for predicting gestational age was assessed in our population to determine comparability between nomograms.

RESULTS

Interobserver and intraobserver variabilities in the second and third trimesters were 3.1% to 3.7% and 3.4% to 3.8%, respectively. Between 14 and 27 weeks' gestation, there were no clinically important differences between our nomogram and those previously published in terms of the predicted gestational age. However, predicted gestational age in the third trimester was considerably different by using our nomogram by 1 to 2 weeks from 28 to 30 weeks and by 4 to 6 weeks after 32 weeks.

CONCLUSION

Transcerebellar measurements had a similar relationship with gestational age across previously published nomograms before 28 weeks. However, clinically significant differences in predicting gestational age appear later, especially after 32 weeks. These findings suggest that this new nomogram may be particularly useful for accurate dating of pregnancies in the third trimester.