Clinical Obstetrics and Epidemiology

The rising trend in pregnancy-related deaths during the past 2 decades in the United States stands out among other high-income countries where pregnancy-related deaths are declining. Cardiomyopathy and other cardiovascular conditions, hemorrhage, and other chronic medical conditions are all important causes of death. Unintentional death from violence, overdose, and self-harm are emerging causes that require medical and public health attention. Significant racial/ethnic inequities exist in pregnancy care with non-Hispanic black women incurring 3 to 4 times higher rates of pregnancy-related death than non-Hispanic white women. Varied terminology and lack of standardized methods for identifying maternal deaths in the United States have resulted in nuanced data collection and interpretation challenges. State maternal mortality review committees are important mechanisms for capturing and interpreting data on cause, timing, and preventability of maternal deaths. Importantly, a thorough standardized review of each maternal death leads to recommendations to prevent future pregnancy-associated deaths. Key interventions to improve maternal health outcomes include 1) integrating multidisciplinary care for women with high-risk comorbidities during preconception care, pregnancy, postpartum, and beyond; 2) addressing structural racism and the social determinants of health; 3) implementing hospital-wide safety bundles with team training and simulation; 4) providing patient education on early warning signs for medical complications of pregnancy; and 5) regionalizing maternal levels of care so that women with risk factors are supported when delivering at facilities with specialized care teams.

Aim: We conducted a systematic review evaluating race/ethnicity representation in DNA methylomic studies of preterm birth. Data sources: PubMed, EMBASE, CINHAL, Scopus and relevant citations from 1 January 2000 to 30 June 2019. Study appraisal & synthesis methods: Two authors independently identified abstracts comparing DNA methylomic differences between term and preterm births that included race/ethnicity data. Results: 16 studies were included. Black and non-Hispanic Black deliveries were well represented (28%). However, large studies originating from more than 95% White populations were excluded due to unreported race/ethnicity data. Most studies were cross-sectional, allowing for reverse causation. Most studies were also racially/ethnically homogeneous, preventing direct comparison of DNA methylomic differences across race/ethnicities. Conclusion: In DNA methylomic studies, Black women and infants were well represented. However, the literature has limitations and precludes drawing definitive conclusions.

OBJECTIVE: Compare the incidence of hypoglycemia in neonates born to patients with diabetes, based on last maternal glucose before delivery.

STUDY DESIGN: Cohort of singleton births from individuals with pregestational and gestational diabetes (GDM) from 2017 to 2019.

RESULTS: We included 853 deliveries. Maternal hyperglycemia before delivery was associated with 1.8-fold greater risk of neonatal hypoglycemia (glucose < 45 mg/dL) in patients with GDM on medication (adjusted risk ratio (aRR): 1.8; 95% CI: 1.1-2.7), compared with euglycemia. This association was not seen in diet-controlled GDM (0.5; 0.23-1.1), nor in Type 1 (1.1; 0.88-1.4), or Type 2 pregestational diabetes (1.1; 0.61-1.9). Further, pregestational diabetes, compared to GDM, regardless of intrapartum maternal glucose control, was associated with neonatal hypoglycemia and NICU admission.

CONCLUSION: Maternal hyperglycemia before delivery only carried a higher risk of neonatal hypoglycemia in those with GDM on medications. Other interventions to reduce neonatal hypoglycemia are needed.

BACKGROUND: Serial growth scans are routinely recommended for twin pregnancies to identify fetal growth restriction (defined as an estimated fetal weight of <10th percentile), which can result in increased perinatal morbidity and mortality. However, the clinical significance of early intertwin growth discordance in the absence of fetal growth restriction remains unclear.

OBJECTIVE: This study aimed to compare the rates of small-for-gestational-age infants among twin pregnancies with intertwin growth discordance in the absence of fetal growth restriction with that among twin pregnancies with concordant, normal growth identified by ultrasound between 24 0/7 and 31 6/7 weeks' gestation.

STUDY DESIGN: This was a retrospective cohort study of twin deliveries at a single hospital from 2010 to 2019. Pregnancies without fetal growth restriction were categorized as discordant or concordant using the earliest prenatal growth ultrasound between 24 0/7 and 31 6/7 weeks' gestation. Discordance was defined as an estimated fetal weight difference of ≥18% between twins. Pregnancies with major fetal anomalies, no growth ultrasound between 24 0/7 and 31 6/7 weeks' gestation, or twin-twin transfusion syndrome were excluded. The cohort was stratified by chorionicity. Our primary outcome was small-for-gestational-age defined as <10th percentile per the Fenton growth curve at delivery. Secondary outcomes included gestational age at delivery, mode of delivery, neonatal intensive care unit admission, length of stay, and neonatal complications and placental pathology.

RESULTS: Of the 707 twin pregnancies that met the inclusion criteria, 558 (79%) were dichorionic and 149 (21%) were monochorionic. Most pregnancies were concordant on ultrasound between 24 0/7 and 31 6/7 weeks' gestation (dichorionic, 93%; monochorionic, 87%). Regardless of chorionicity, twin pregnancies with discordance at ultrasound, were more likely to have a small-for-gestational-age infant than concordant twin pregnancies (dichorionic: 51% vs 29%; P=.002; monochorionic: 65% vs 24%; P<.001). Furthermore, women with twin pregnancies with discordance were delivered at an earlier gestational age (dichorionic: 36 weeks [interquartile range, 33-36] vs 34 weeks [interquartile range, 34-38]; P<.001; monochorionic: 34 weeks [interquartile range, 32-34] vs 36 weeks [interquartile range, 34-37]; P=.003). Pregnancies with growth discordance were more likely to be delivered by cesarean delivery (dichorionic: 90% vs 72%; P=.01; monochorionic: 65% vs 60%; P=.70), although this was only statistically significant for dichorionic twin pregnancies. Neonates of pregnancies with growth discordance had a higher incidence of respiratory distress syndrome (dichorionic: 54% vs 37%; P=.04; monochorionic: 70% vs 45%; P=.04) and neonatal intensive care unit admission (dichorionic: 71% vs 50%; P=.01; monochorionic: 90% vs 65%; P=.03). Furthermore, dichorionic infants had longer neonatal intensive care unit stays (30 [interquartile range, 18-61] vs 18 [interquartile range, 10-35] days; P=.02).

CONCLUSION: Regardless of chorionicity, twin pregnancies with discordance without fetal growth restriction identified on growth ultrasound between 24 0/7 and 31 6/7 weeks' gestation were nearly twice as likely to develop small-for-gestational-age neonates, deliver earlier in gestation, and experience greater neonatal morbidity than twin pregnancies without discordance. Patients with pregnancies complicated by isolated intertwin discordance between 24 0/7 and 31 6/7 weeks' gestation will need counseling regarding adverse perinatal outcomes.

BACKGROUND: Ischaemic placental disease (IPD) affects 16%-23% of pregnancies in the United States. In vitro fertilisation (IVF) is a risk factor for IPD, and the magnitude of increase in risk differs for individuals using donor oocytes (donor IVF) versus their own oocytes (autologous IVF). In addition, multifoetal gestations, which are more common in IVF than non-IVF pregnancies, also are a risk factor for IPD.

OBJECTIVE: To quantify the contribution of multifoetal gestations to the association between IVF and IPD.

METHODS: We conducted a retrospective cohort study at a tertiary hospital from 1 January, 2000 to 1 August 2018 using electronic medical records and state vital statistics data. IPD was defined as preeclampsia, placental abruption, small for gestational age (SGA) birth or an intrauterine foetal demise due to placental insufficiency. We used mediation analysis to decompose the total effect of IVF on IPD into a natural direct effect and an indirect effect through multifoetal gestations. We repeated the analyses separately for donor and autologous IVF. All models were adjusted for maternal age, race, parity, insurance, year of delivery and account for multiple pregnancies per person.

RESULTS: We identified 86,514 deliveries, of which 281 resulted from donor IVF and 4173 resulted from autologous IVF. IVF pregnancies had 1.99 (95% CI 1.88, 2.10) times the risk of IPD compared to non-IVF pregnancies, and 75.5% of this increased risk was mediated by multifoetal gestations. Autologous IVF pregnancies had 1.95 (95% CI 1.84, 2.07) times the risk of IPD compared to non-IVF pregnancies, and the per cent mediated was 78.8%. Donor IVF pregnancies had 2.50 (95% CI 2.09, 2.92) times the risk of IPD, but the per cent mediated was 37.5%.

CONCLUSION: The majority of the association between autologous IVF and IPD was mediated through multifoetal gestations; however, this was not the case for donor IVF pregnancies.

The COVID-19 pandemic has generated an unprecedented amount of novel and repurposed vaccines and therapeutics that have been rapidly developed and implemented into clinical use. Unfortunately, pregnant persons have been excluded from most phase III clinical studies; therefore, our understanding regarding their safety for use in this population stems from understanding of theoretic risks and observational data. In this review, the authors discuss pregnancy-specific considerations for COVID-19 therapeutics.

PURPOSE: In the US, preterm birth (PTB) is 55% more common among Black compared to White individuals and psychosocial stressors may contribute. Resilience is associated with improved health outcomes; whether it modifies PTB inequity is unknown. We hypothesized high resilience would reduce inequities in PTB risk.

METHODS: This study analyzes data from 535 pregnancies among Black (n = 101, 19%) and White (n = 434, 81%) participants from a prospective cohort. Participants completed the Connor-Davidson Resilience Scale. We calculated risk ratios (RR) stratified by resilience tertiles to test for effect measure modification.

RESULTS: Among those in the lowest resilience tertile, there were six (20.7%) PTBs among Black and seven (4.9%) among White participants (RR: 4.26; 95% confidence interval (CI): 1.53, 11.81). Among those in the highest resilience tertile, there were 8 (18.2%) PTBs among Black and 14 (9.5%) among White participants (RR: 1.92; 95% CI: 0.87, 4.24. The adjusted Black:White RR was 2.00 (95% CI 0.47, 8.64) in the lowest and 3.49 (95% CI 1.52, 8.01) in the highest tertile.

CONCLUSIONS: Black-White PTB inequity did not differ among resilience strata and remained significant in the highest tertile. Our findings suggest that high resilience is inadequate to overcome Black:White racial inequity in PTB.

Borrelia miyamotoi disease (BMD), also known as hard-tick relapsing fever, is an emerging tick-borne illness caused by the bacterium Borrelia miyamotoi. This pathogen is transmitted primarily by Ixodes ticks, also known as deer ticks or black-legged ticks. BMD poses significant public health concerns because of its potential to cause severe hemodynamic and hematologic disturbances, particularly in vulnerable populations such as pregnant individuals. BMD often presents with symptoms like other tick-borne infections, including fever, chills, headache, and muscle aches, but often lacks the characteristic rash seen in Lyme disease and does not typically have a greater-than-24-hour tick attachment period for transmission. A high index of suspicion in the late spring and summer months in the Northern hemisphere is essential for early diagnosis of BMD and treatment to prevent maternal and neonatal morbidity and mortality.