Single-center serological surveillance of SARS-CoV-2 in pregnant patients presenting to labor and delivery.

OBJECTIVE: To measure maternal/fetal SARS-CoV-2 antibody levels. METHODS: A prospective observational study of eligible parturients admitted to the hospital for infant delivery was conducted between April and September 2020. SARS-CoV-2 antibody levels were measured in maternal and umbilical cord specimens using an in-house ELISA based on the receptor-binding domain (RBD) of the spike protein. Among SARS-CoV-2 seropositive patients, spike RBD antibody isotypes (IgG, IgM, and IgA) and ACE2 inhibiting antibodies were measured. RESULTS: In total, 402 mothers were enrolled and spike RBD antibodies in 388 pregnancies were measured (336 maternal and 52 cord specimens). Of them, 19 were positive (15 maternal, 4 cord) resulting in a seroprevalence estimate of 4.8% (95% confidence interval 2.9-7.4). Of the 15 positive maternal specimens, all had cord blood tested. Of the 15 paired specimens, 14 (93.3%) were concordant. Four of the 15 pairs were from symptomatic mothers, and all four showed high spike-ACE2 blocking antibody levels, compared to only 3 of 11 (27.3%) from asymptomatic mothers. CONCLUSION: A variable antibody response to SARS-CoV-2 in pregnancy among asymptomatic infections compared to symptomatic infections was found, the significance of which is unknown. Although transfer of transplacental neutralizing antibodies occurred, additional research is needed to determine how long maternal antibodies can protect the infant against SARS-CoV-2 infection.

Inertial Measurement Unit-Assisted Ultrasonic Tracking System for Ultrasound Probe Localization.

Ultrasonic tracking is a promising technique in indoor object localization. However, limited success has been reported in dynamic orientational and positional ultrasonic tracking for ultrasound (US) probes due to its instability and relatively low accuracy. This article aims at developing an inertial measurement unit (IMU)-assisted ultrasonic tracking system that enables a high accuracy positional and orientational localization. The system was designed with the acoustic pressure field simulation of the transmitter, receiver configuration, position-variant error simulation, and sensor fusion. The prototype was tested in a tracking volume required in typical obstetric sonography within the typical operation speed ranges (slow mode and fast mode) of US probe movement. The performance in two different speed ranges was evaluated against a commercial optical tracking device. The results show that the proposed IMU-assisted US tracking system achieved centimeter-level positional tracking accuracy with the mean absolute error (MAE) of 12 mm and the MAE of orientational tracking was less than 1°. The results indicate the possibility of implementing the IMU-assisted ultrasonic tracking system in US probe localization.

Toward Automated Analysis of Fetal Phonocardiograms: Comparing Heartbeat Detection from Fetal Doppler and Digital Stethoscope Signals.

Longitudinal fetal health monitoring is essential for high-risk pregnancies. Heart rate and heart rate variability are prime indicators of fetal health. In this work, we implemented two neural network architectures for heartbeat detection on a set of fetal phonocardiogram signals captured using fetal Doppler and a digital stethoscope. We test the efficacy of these networks using the raw signals and the hand-crafted energy from the signal. The results show a Convolutional Neural Network is the most efficient at identifying the S1 waveforms in a heartbeat, and its performance is improved when using the energy of the Doppler signals. We further discuss issues, such as low Signal-to-Noise Ratios (SNR), present in the training of a model based on the stethoscope signals. Finally, we show that we can improve the SNR, and subsequently the performance of the stethoscope, by matching the energy from the stethoscope to that of the Doppler signal.

An automated framework for image classification and segmentation of fetal ultrasound images for gestational age estimation.

Accurate assessment of fetal gestational age (GA) is critical to the clinical management of pregnancy. Industrialized countries rely upon obstetric ultrasound (US) to make this estimate. In low- and middle- income countries, automatic measurement of fetal structures using a low-cost obstetric US may assist in establishing GA without the need for skilled sonographers. In this report, we leverage a large database of obstetric US images acquired, stored and annotated by expert sonographers to train algorithms to classify, segment, and measure several fetal structures: biparietal diameter (BPD), head circumference (HC), crown rump length (CRL), abdominal circumference (AC), and femur length (FL). We present a technique for generating raw images suitable for model training by removing caliper and text annotation and describe a fully automated pipeline for image classification, segmentation, and structure measurement to estimate the GA. The resulting framework achieves an average accuracy of 93% in classification tasks, a mean Intersection over Union accuracy of 0.91 during segmentation tasks, and a mean measurement error of 1.89 centimeters, finally leading to a 1.4 day mean average error in the predicted GA compared to expert sonographer GA estimate using the Hadlock equation.

Performance Enhanced Ultrasound Probe Tracking With a Hemispherical Marker Rigid Body.

Among tracking techniques applied in the 3-D freehand ultrasound (US), the camera-based tracking method is relatively mature and reliable. However, constrained by manufactured marker rigid bodies, the US probe is usually limited to operate within a narrow rotational range before occlusion issues affect accurate and robust tracking performance. Thus, this study proposed a hemispherical marker rigid body to hold passive noncoplanar markers so that the markers could be identified by the camera, mitigating self-occlusion. The enlarged rotational range provides greater freedom for sonographers while performing examinations. The single-axis rotational and translational tracking performances of the system, equipped with the newly designed marker rigid body, were investigated and evaluated. Tracking with the designed marker rigid body achieved high tracking accuracy with 0.57° for the single-axis rotation and 0.01 mm for the single-axis translation for sensor distance between 1.5 and 2 m. In addition to maintaining high accuracy, the system also possessed an enhanced ability to capture over 99.76% of the motion data in the experiments. The results demonstrated that with the designed marker rigid body, the missing data were remarkably reduced from over 15% to less than 0.5%, which enables interpolation in the data postprocessing. An imaging test was further conducted, and the volume reconstruction of a four-month fetal phantom was demonstrated using the motion data obtained from the tracking system.

Travel Medicine: Clinical Updates in Women's Health Care Primary and Preventive Care Review.

Travel is an increasingly common aspect of modern life, and the practicing obstetrician-gynecologist needs a good understanding of the health- and safety-related issues it presents for patients. This monograph examines the environmental data that support individual risk assessment and provides guidance on how to eliminate or mitigate those risks, including recommendations for immunization and chemoprophylaxis for women traveling to areas with endemic infectious disease. Management approaches for travel-related diseases, such as traveler's diarrhea, altitude sickness, and location-specific diseases, are reviewed as are special considerations for pregnant and breastfeeding women and women who are attempting pregnancy. Evaluation and management of the returned traveler also is addressed. The recommendations in this document cite resources available from the United States federal government; therefore, they are applicable to women seeking care in the United States.

Pharmacotherapy during Pregnancy: An Endodontic Perspective.

Odontogenic pain affects up to 54.9% of pregnant women1-3. This pain is often associated with pulpal and/or periapical infections that pose risks to women and their fetus. The American Dental Association in collaboration with the American College of Obstetricians and Gynecologists developed a consensus statement to affirm the importance of timely and appropriate oral health care as a critical component of a healthy pregnancy4. However, limited knowledge of endodontic procedure safety and related medication use often result in the avoidance of treatment during pregnancy. This article, a collaborative effort by specialists from endodontics, pediatric dentistry, and obstetrics, reviews the current evidence on the safety of medications commonly used in endodontics including local anesthetics, analgesics, anxiolytics, and antibiotics.

Use and experiences with external fetal monitoring devices among obstetrical providers.

Introduction: Fetal heart rate monitoring presents one of the few available methods for evaluating the fetus prior to birth. However, current devices on the market have significant shortcomings. We sought to describe the use and experiences with external fetal monitoring (EFM) devices among obstetrical providers.Materials and methods: We performed a cross-sectional survey in an academic medical center between April and July 2017 including nurse, midwife, and physician obstetrical providers (n = 217) who were invited to participate in this study regarding their experiences with the external fetal monitoring (EFM) device utilized by their hospital system in the outpatient, inpatient, and labor and delivery (L&D) settings. Associations between provider characteristics, device use, perception of challenging patients, and potential usefulness of an improved system were assessed by Fisher's exact test.Results: The 137 respondents (63.1%) reported difficulties monitoring obese women (98.5%), multiple gestation pregnancies (90.5%), and early gestational ages (71.5%). Over half (59.5%) of L&D nurses reported interacting with EFM devices for greater than 1-hour during a typical 12-hour shift and fewer than half (42.3%) reported being satisfied with current EFM devices. There were no statistically significant associations between provider age, experience, or time spent utilizing the devices with perception of challenging patient types.Conclusions: In conclusion, obstetrical providers perceive shortcomings of current EFM devices across all levels of provider experience and time utilizing these devices. Nurses reported significant time operating the devices, representing an opportunity to reduce time and costs with an improved device.

Improving Access to Laparoscopy in Low-Resource Settings.

Laparoscopy has numerous clinical benefits compared to laparotomy. However, a functional laparoscopy program requires significant investment and, as a result, remains unavailable for the majority of the world's population in low- and middle-income countries. The effort to bring laparoscopy to low-resource settings has produced variable outcomes resulting from the challenges inherent to a complex surgical program. This paper highlights these shortcomings and identifies opportunities to improve future laparoscopy programs.

Factors affecting attendance to cervical cancer screening among women in the Paracentral Region of El Salvador: a nested study within the CAPE HPV screening program.

BACKGROUND: Cervical cancer is the third most commonly occurring cancer among women and the fourth leading cause of cancer-related deaths in women worldwide, with more than 85 % of these cases occurring in developing countries. These global disparities reflect the differences in cervical cancer screening rates between high-income and medium- and low-income countries. At 19 %, El Salvador has the lowest reported screening coverage of all Latin American countries. The purpose of this study is to identify factors affecting public sector HPV DNA-based cervical cancer screening participation in El Salvador. METHODS: This study was nested within a public sector screening program where health promoters used door-to-door outreach to recruit women aged 30-49 years to attend educational sessions about HPV screening. A subgroup of these participants was chosen randomly and questioned about demographic factors, healthcare utilization, previous cervical cancer screening, and HPV knowledge. Women then scheduled screening appointments at their public health clinics. Screening participants were adherent if they attended their scheduled appointment or rescheduled and were screened within 6 months. The association between non-adherence and demographic variables, medical history, history of cancer, sexual history, birth control methods, and screening barriers was assessed using Chi-square tests of significance and logistic regression. RESULTS: All women (n = 409) enrolled in the study scheduled HPV screening appointments, and 88 % attended. Non-adherence was associated with a higher number of lifetime partners and being under-screened-defined as not having participated in cervical cancer screening within the previous 3 years (p = 0.03 and p = 0.04, respectively); 22.8 % of participants in this study were under-screened. CONCLUSIONS: Adherence to cervical cancer screening after educational sessions was higher than expected, in part due to interactions with the community-based health promoters as well as the educational session itself. More effective recruitment methods targeted toward under-screened women are required.

Acceptability of self-collected versus provider-collected sampling for HPV DNA testing among women in rural El Salvador.

OBJECTIVE: To determine the acceptability of self-collected versus provider-collected sampling among women participating in public sector HPV-based cervical cancer screening in El Salvador. METHODS: Two thousand women aged 30-49 years underwent self-collected and provider-collected sampling with careHPV between October 2012 and March 2013 (Qiagen, Gaithersburg, MD, USA). After sample collection, a random sample of women (n=518) were asked about their experience. Participants were questioned regarding sampling method preference, previous cervical cancer screening, HPV and cervical cancer knowledge, HPV risk factors, and demographic information. RESULTS: All 518 women approached to participate in this questionnaire study agreed and were enrolled, 27.8% (142 of 511 responding) of whom had not received cervical cancer screening within the past 3 years and were considered under-screened. Overall, 38.8% (n=201) preferred self-collection and 31.9% (n=165) preferred provider collection. Self-collection preference was associated with prior tubal ligation, HPV knowledge, future self-sampling preference, and future home-screening preference (P<0.05). Reasons for self-collection preference included privacy/embarrassment, ease, and less pain; reasons cited for provider-collection preference were result accuracy and provider knowledge/experience. CONCLUSION: Self-sampling was found to be acceptable, therefore screening programs could consider offering this option either in the clinic or at home. Self-sampling at home may increase coverage in low-resource countries and reduce the burden that screening places upon clinical infrastructure.