Using Parametric g-Computation for Time-to-Event Data and Distributed Lag Models to Identify Critical Exposure Windows for Preterm Birth: An Illustrative Example Using in a Retrospective Birth Cohort Based in Eastern Massachusetts (2011-2016).

Background: Parametric g-computation is an attractive analytic framework to study the health effects of air pollution. Yet, the ability to explore biologically relevant exposure windows within this framework is underdeveloped.

Objectives: We outline a novel framework for how to incorporate complex lag-responses using distributed lag models (DLMs) into parametric g-computation analyses for survival data.

Cerclage Plus Adjuvant Vaginal Progesterone for Preterm Birth Prevention in Patients with a Short or Dilated Cervix without Prior Preterm Birth.

Objective:  The primary objective was to determine if vaginal progesterone following cerclage for cervical length <10 mm or cervical dilation in patients without a history of spontaneous preterm birth (sPTB) decreased the risk of preterm birth at <34 weeks' gestation compared with cerclage alone. Secondary objectives were to determine if vaginal progesterone following cerclage (1) decreased the risk of preterm birth at <24, <28, and <37 weeks' gestation and (2) increased the latency period from cerclage placement to delivery compared with treatment with cerclage alone.

Study Design:  Multicenter retrospective cohort study from 2015 to 2020 of singleton pregnancies, without prior sPTB, who had cerclage placement <24 weeks' gestation for cervical length <10 mm or cervical dilation.

Risk Profiling In Vitro Fertilization Pregnancies that Develop Placenta Accreta Spectrum.

Objective:  The objective of this study is to assess whether, among a cohort of placenta accreta spectrum (PAS) patients, antenatal suspicion of PAS was less likely in in vitro fertilization (IVF) compared with non-IVF patients. In addition, we aimed to assess whether IVF patients exhibited similar risk factors for PAS compared with non-IVF patients.

Study Design:  This is an international multicenter retrospective study of patients with pathologically confirmed PAS (accreta, increta, percreta) between 1998 and 2021.

Association between gestational exposure to solar activity and pregnancy loss using live births from a Massachusetts-based medical center.

Background: Solar activity has been linked to biological mechanisms important to pregnancy, including folate and melatonin levels and inflammatory markers. Thus, we aimed to investigate the association between gestational solar activity and pregnancy loss.

Methods: Our study included 71,963 singleton births conceived in 2002-2016 and delivered at an academic medical center in Eastern Massachusetts.

Novel interactive text-messaging curriculum for endocrinology board review.

Background: The ABIM certification exam is one of the measures to ensure that physicians have the clinical skills for good care delivery. The 5-year average pass rate for ABIM Endocrinology exam is 82%. The pass rate significantly decreased to a nadir of 74% in 2021 and 2022, lowest of all medicine subspecialties.

Basal Plate Myofibers and the Risk of Placenta Accreta Spectrum in the Subsequent Pregnancy: A Large Single-Center Cohort.

Objective: We aimed to evaluate whether there is a significant association between a placental pathology diagnosis basal plate myofibers (BPMF) in an index pregnancy with placenta accreta spectrum (PAS) in the subsequent pregnancy.

Study Design: We conducted a retrospective nested cohort study of all cases with a histopathological finding of BPMF between August 2012 and March 2020 at a single tertiary referral center. Data were collected for all subjects (cases and controls) with at least two consecutive pregnancies (the initial index pregnancy and at least one subsequent pregnancy) accompanied by a concomitant record of histopathological study of the placenta at our center.

Associations of solar activity and related exposures with fetal growth.

Background: Solar and geomagnetic activity have been shown to suppress melatonin and to degrade folate levels, important hormones for fetal development. We examined whether solar and geomagnetic activity were associated with fetal growth.

Methods: We included 9573 singleton births with 26,879 routine ultrasounds at an academic medical center in Eastern Massachusetts from 2011 through 2016.

Delay in Surgery and Papillary Thyroid Cancer Survival in the United States: A SEER-Medicare Analysis.

Introduction: Delays in surgery and their impact on survival in papillary thyroid cancer (PTC) is unclear. We sought to investigate the association between time to surgery and survival in patients with PTC.

Methods: A total of 8170 Medicare beneficiaries with PTC who underwent thyroidectomy were identified within the Surveillance, Epidemiology, and End Results-Medicare linked data files between 1999 and 2018.

Traffic-Related Air Pollution and Ultrasound Parameters of Fetal Growth in Eastern Massachusetts.

Previous studies have examined the association between prenatal nitrogen dioxide (NO2)-a traffic emissions tracer-and fetal growth based on ultrasound measures. Yet, most have used exposure assessment methods with low temporal resolution, which limits the identification of critical exposure windows given that pregnancy is relatively short. Here, we used NO2 data from an ensemble model linked to residential addresses at birth to fit distributed lag models that estimated the association between NO2 exposure (resolved weekly) and ultrasound biometric parameters in a Massachusetts-based cohort of 9,446 singleton births from 2011-2016.

Androgenetic alopecia incidence in transgender and gender diverse populations: A retrospective comparative cohort study.

Background: Androgenetic alopecia (AGA) is a significant challenge for many transgender and gender diverse (TGD) patients, but the rate of AGA among TGD patients receiving gender-affirming hormone therapy (GAHT) compared to cisgender patients has not yet been studied on a large scale.

Objective: We examined the incidence of AGA among TGD patients receiving GAHT compared to cisgender patients.

Methods: Retrospective cohort study using electronic health records from 37,826 patients seen at Fenway Health between August 1, 2014, and August 1, 2020.

Altered Cytokine Production in Human Intervillous Blood T Cells in Preeclampsia.

Conventional and regulatory T cells (Treg) are dynamic mediators of maternal immune tolerance to the developing feto-placental unit. Functional evaluation of T cells at the maternal-fetal interface is crucial to elucidate the immunologic basis of obstetric complications. Our objective was to define the T cell phenotype and function of uterine intervillous blood (IVB) in pregnancy with and without preeclampsia.

Bias Amplification and Variance Inflation in Distributed Lag Models Using Low-Spatial-Resolution Data.

Distributed lag models (DLMs) are often used to estimate lagged associations and identify critical exposure windows. In a simulation study of prenatal nitrogen dioxide (NO2) exposure and birth weight, we demonstrate that bias amplification and variance inflation can manifest under certain combinations of DLM estimation approaches and time-trend adjustment methods when using low-spatial-resolution exposures with extended lags. Our simulations showed that when using high-spatial-resolution exposure data, any time-trend adjustment method produced low bias and nominal coverage for the distributed lag estimator.

Ambient temperature during pregnancy and fetal growth in Eastern Massachusetts, USA.

Background: Left unabated, rising temperatures pose an escalating threat to human health. The potential effects of hot temperatures on fetal health have been under-explored. Here, we examined the association between prenatal ambient temperature exposure and fetal growth measures in a Massachusetts-based pregnancy cohort.

Association of Early Beta Human Chorionic Gonadotropin With Ischemic Placental Disease in Singleton Pregnancies After In Vitro Fertilization.

Objectives: To evaluate whether an initial or two-day percent increase in serum beta-human chorionic gonadotropin (βhCG) is associated with ischemic placental disease (IPD) in singleton pregnancies after autologous or donor IVF.

Study Design: This was a secondary analysis of a retrospective cohort study of deliveries linked to IVF cycles at a single academic tertiary hospital and infertility treatment center. We included all patients (≥18 years old) who had a singleton live birth or intrauterine fetal demise (IUFD) resulting from either autologous fresh (n=1,347), autologous frozen (n=454), or donor (n=253) IVF cycles.

The Association between Placenta Accreta Spectrum Severity and Incidence of Small for Gestational Age Neonates.

Objective: The aim of the study is to evaluate whether pathologic severity of placenta accreta spectrum (PAS) is correlated with the incidence of small for gestational age (SGA) and neonatal birthweight.

Study Design: This was a multicenter cohort study of viable, non-anomalous, singleton gestations delivered with histology-proven PAS. Data including maternal history, neonatal birthweight, and placental pathology were collected and deidentified.

Effect of Widespread Sleep Apnea Screening on Progression of Atrial Fibrillation.

Sleep apnea (SA) is recognized as a predictor of incident atrial fibrillation (AF) and AF recurrence after treatment. However, data on the prevalence of SA phenotypes in patients with AF and the effect of widespread SA screening on AF outcomes are scarce. We conducted a retrospective study of patients with AF referred for SA testing between March 2018 and April 2020.

A novel approach to joint prediction of preeclampsia and delivery timing using semicompeting risks.

Background: Preeclampsia is a pregnancy complication that contributes substantially to perinatal morbidity and mortality worldwide. Existing approaches to modeling and prediction of preeclampsia typically focus either on predicting preeclampsia risk alone, or on the timing of delivery following a diagnosis of preeclampsia. As such, they are misaligned with typical healthcare interactions during which the 2 events are generally considered simultaneously.

PCOS and the risk of pre-eclampsia.

Research Question: What is the association between polycystic ovary syndrome (PCOS) and pre-eclampsia? Data suggest that patients with PCOS are at increased risk of developing pre-eclampsia; however, several studies have not found an independent association between the two.

Design: A retrospective case-control study of singleton deliveries at a tertiary care hospital from 2011 to 2015. Patients with pre-eclampsia (cases) were matched to the next delivery without pre-eclampsia (controls) on gestational age week.