Use or overuse of antenatal corticosteroids for suspected preterm birth

Use, misuse, and overuse of antenatal corticosteroids. A retrospective cohort study

OBJECTIVES

To evaluate the timing of antenatal corticosteroids (ACS) administration in relation to the delivery timing based on indications and risk factors for preterm delivery.

METHODS

We conducted a retrospective cohort study to understand what factors predict the optimal timing of ACS administration (ACS administration within seven days). We reviewed consecutive charts of adult pregnant women receiving ACS from January 1, 2011, to December 31, 2019. We excluded pregnancies under 23 weeks, incomplete and duplicate records, and patients delivered outside our health system. The timing of ACS administration was categorized as optimal or suboptimal. These groups were analyzed regarding demographics, indications for ACS administration, risk factors for preterm delivery, and signs and symptoms of preterm labor.

RESULTS

We identified 25,776 deliveries. ACS were administered to 531 pregnancies, of which 478 met the inclusion criteria. Of the 478 pregnancies included in the study, 266 (55.6 %) were delivered in the optimal timeframe. There was a higher proportion of patients receiving ACS for the indication of threatened preterm labor in the suboptimal group as compared to the optimal group (85.4 % vs. 63.5 %, p<0.001). In addition, patients who delivered in the suboptimal timeframe had a higher proportion of short cervix (33 % vs. 6.4 %, p<0.001) and positive fetal fibronectin (19.8 % vs. 1.1 %, p<0.001) compared to those who delivered in the optimal timeframe.

CONCLUSIONS

More emphasis should be placed on the judicious use of ACS. Emphasis should be placed on clinical assessment rather than relying solely on imaging and laboratory tests. Re-appraisal of institutional practices and thoughtful ACS administration based on the risk-benefit ratio is warranted.

Fetal lung maturity assessment: A historic perspective and Non - invasive assessment using an automatic quantitative ultrasound analysis (a potentially useful clinical tool)

Immature fetal lung is associated with many adverse outcomes including respiratory distress syndrome and transient tachypnoea of the newborn. Several methods/tools have been used over several decades to assess fetal lung maturity prior to delivery. Some of the methods that have been used to assess fetal lung maturity include amniocentesis for the biochemical markers, lecithin and sphingomyelin, lamellar body counts, gray scale ultrasound scan and magnetic resonance imaging. Amniocentesis an invasive procedure which carries a small risk of miscarriage has almost become obsolete. Magnetic resonance imaging on the other hand is expensive and not very practical. Quantitative ultrasound fetal lung maturity (quantusFLM) assessment is a new technique aimed at assessing fetal lung texture using ultrasound. The technique depends on visualization of fetal lungs at the level of the 4- chamber view. Images obtained are then uploaded via a web page application and these are analyzed remotely and results generated in minutes. The analysis depends on studying changes in the texture of lung images that depend on changes at histological level especially of collagen, fat and water. These changes are undetectable to the human eye. Randomized clinical trials have shown this technique to be accurate, reproducible, and completely non - invasive. The aim of this review was to take a historic look at methods/tools for assessing fetal lug maturity and discuss further advances and a potential non-invasive tool/method especially the non-invasive assessment that combines ultrasound scan and machine learning to accurately assess lung maturity.

Exposure to Infliximab During Pregnancy: Post-Marketing Experience

Background

Women of childbearing potential are often treated with monoclonal antibodies to control chronic and debilitating inflammatory diseases. Remicade^® (innovator infliximab [IFX]) may cross the placenta after the first trimester of pregnancy. Hence, evidence is needed to optimize treatment while carefully weighing benefits and risks to the mother and child. Here, we report on birth and infant outcomes (up to 2 years) following gestational exposure to IFX based on a summary of cumulative pregnancy reports in women exposed to IFX during pregnancy from the Janssen global safety database.

Methods

Prospective and medically confirmed safety data on IFX-exposed pregnancies from Janssen’s global safety surveillance database since authorization in 1998 are summarized. Descriptive statistics were used to summarize pregnancy and infant outcomes overall, by disease and timing of exposure.

Results

As of 23 August 2018, 1850 maternally IFX-exposed pregnancies with known outcomes were identified from the safety database. Of the 1850 pregnancies (mean age 29.7 years), 1526 (82.5%) resulted in live births. When reported, most women had Crohn’s disease (67.7%) or ulcerative colitis (18.4%), and 82.8% of live births were exposed to IFX in the first trimester. Spontaneous abortion/intrauterine death/ectopic pregnancy/molar pregnancy (12.1%), preterm births (9.2%), low birth weight infants (3.6%), congenital anomalies (2.0%), and infant infections (1.2%) were documented. The type of congenital anomalies and frequency of serious infant infections observed were consistent with the general population. Frequencies of congenital anomalies and other adverse outcomes were similar in women exposed to IFX in the first trimester and those exposed in the third trimester. More preterm births (13–18.8%) and infant complications (8.7–12.5%) were reported with concomitant immunosuppressant use.

Conclusions

The observed prevalence of adverse pregnancy and infant outcomes including congenital anomalies following exposure to IFX did not exceed estimates reported for the general population and no unexpected patterns were observed.

Controversies in antenatal corticosteroid treatment

Antenatal corticosteroids are now established as one of the cornerstones of therapy in the prevention of neonatal morbidity and mortality prior to preterm birth. Although this practice is widely accepted, a significant number of controversies exist. This review explores the knowledge gaps regarding the use of antenatal corticosteroids in the preterm, late preterm and term populations. Furthermore, the role of antenatal corticosteroids in special populations, such as diabetes, multiple pregnancies and periviable gestations, where high-quality data from randomized controlled trials are lacking, is also considered.

Oxidative stress - Related spontaneous preterm delivery challenges in causality determination, prevention and novel strategies in reduction of the sequelae

Spontaneous preterm birth (PTB) is one of the major complications of pregnancy and the main cause of neonatal mortality and morbidity. Despite the efforts devoted to the understanding of this obstetrical syndrome and improved medical care, there has been a tendency for the PTB rate to increase in the last decades globally. The costs of the screening for spontaneous PTB, its management, and treatment of the sequelae represent a major burden to the health service economy of high-income countries. In this scenario, it has been widely acknowledged that oxidative stress (OS) plays an important role in the pathogenicity of human disease in wide range of areas of medicine. There is an emerging evidence that an imbalance between pro-and-antioxidants may be associated with spontaneous PTB. However, there are still many controversies on the mechanisms by which OS are involved in the pathogenesis of prematurity. Moreover, the crucial question whether the OS is the cause or consequence of the disease is yet to be answered. The purpose of this article is to briefly summarize the current knowledge and controversies on oxidative stress-related spontaneous PTB and to give a critical approach on future perspectives on this topic as a classical example of translational medicine. Placenta-mediated pregnancy adverse outcome associated with OS leading to iatrogenic PTB (e.g. pre-eclampsia, intrauterine growth restriction, gestational diabetes) will not be discussed.

Analysis of clinical diagnosis for all patients receiving antenatal betamethasone in a community hospital

OBJECTIVE

Identify which obstetrical diagnoses are associated with suboptimal antenatal betamethasone administration.

METHODS

We present a retrospective, cohort study of patients who received betamethasone due to a risk for preterm delivery, between 7/2013 and 9/2016 at our institution. Details of betamethasone administration were recorded including the diagnosis leading to betamethasone. Optimal administration was defined as two doses of betamethasone given 24 hours apart, with delivery occurring at greater than 24 hours but less than seven days after completion of the second dose of betamethasone. Suboptimal administration included any betamethasone dosing that did not meet the optimal criteria.

RESULTS

428 patients were identified for the study with 20.1% of patients receiving optimal betamethasone. Patients presenting with hypertensive disorders of pregnancy (36.1%) and preterm premature rupture of membranes (PPROM) (22.1%) were more likely to receive optimal betamethasone, while patients presenting with preterm labor (PTL) (41.8%) and placental abruption (24.6%) were more likely to receive suboptimal betamethasone (p-value < 0.0001). Among PTL patients, those presenting with contractions and cervical dilation/short cervix (19.15%) were more likely to receive optimal betamethasone (p-value 0.0349). Optimal betamethasone decreased the incidence of respiratory distress syndrome (RDS) among 32.1 to 34 week neonates.

CONCLUSION

Hypertensive disorders of pregnancy and PPROM are associated with optimal betamethasone, whereas PTL and placental abruption are associated with suboptimal betamethasone.

Trends in receipt of single and repeat courses of antenatal corticosteroid administration among preterm and term births: A retrospective cohort study

AIM

To investigate trends in receipt and timing of antenatal corticosteroid (ACS) administration over a ten-year interval.

METHODS

Retrospective cohort study of all live births from 2006 to 2015 occurring at a tertiary level teaching hospital in Adelaide, Australia. We analysed temporal trends in the receipt of single courses and repeat doses of ACSs, according to administration timing prior to birth. The main outcome measures were receipt of a single course of ACS and whether administration was 'Optimal' (≥24 h to <seven days) or 'Suboptimal' (<24 h OR ≥7 days) according to timing prior to birth, as well as administration of repeat doses.

RESULTS

Among 47 105 live births, 4191 (8.9%) received any ACS, while 1009 (2.1%) received at least one repeat dose. From 2006/7 to 2014/15, receipt of a single course (relative risk (RR) 1.33; 95%CI 1.21, 1.47) or repeat dose of ACS (RR 1.24; 95%CI 1.01, 1.55) increased. Among women giving birth between 23-34 weeks gestation, receipt of any ACS increased from 75 to 84%, while an optimally timed single course of ACS increased from 20.4 to 31.0% (RR 1.40; 95%CI 1.24, 1.87). From 2006/7 to 2014/15, the greatest increase in ACS administration was evident among infants born 35-36 and ≥37 weeks gestation by caesarean section (RR 1.94; 95%CI 1.48, 2.55 and RR 2.55; 95%CI 1.86, 3.50, respectively).

CONCLUSIONS

While frequently used, less than half of ACS administration prior to preterm birth was optimally timed. The impact of suboptimal ACS timing on neonatal outcomes requires further investigation.

Timing of delivery in a high-risk obstetric population: a clinical prediction model

BACKGROUND

The efficacy of antenatal corticosteroid treatment for women with threatened preterm birth depends on timely administration within 7 days before delivery. We modelled the probability of delivery within 7 days of admission to hospital among women presenting with threatened preterm birth, using routinely collected clinical characteristics.

METHODS

Data from the Canadian Perinatal Network (CPN) were used, 2005-11, including women admitted to hospital with preterm labour, preterm pre-labour rupture of membranes, short cervix without contractions, or dilated cervix or prolapsed membranes without contractions at preterm gestation. Women with fetal anomaly, intrauterine fetal demise, twin-to-twin transfusion syndrome, and quadruplets were excluded. Logistic regression was undertaken to create a predictive model that was assessed for its calibration capacity, stratification ability, and classification accuracy (ROC curve).

RESULTS

We included 3012 women admitted at 24-28 weeks gestation, or readmitted at up to 34 weeks gestation, to 16 tertiary-care CPN hospitals. Of these, 1473 (48.9%) delivered within 7 days of admission. Significant predictors of early delivery included maternal age, parity, gestational age at admission, smoking, preterm labour, prolapsed membranes, preterm pre-labour rupture of membranes, and antepartum haemorrhage. The area under the ROC curve was 0.724 (95% CI 0.706-0.742).

CONCLUSION

We propose a useful tool to improve prediction of delivery within 7 days after admission among women with threatened preterm birth. This information is important for optimal corticosteroid treatment.

Antenatal steroids for fetal lung maturity: Time to target more frequent doses to fewer women?

Antenatal corticosteroids for fetal lung maturation have become mainstay treatment in women thought to be at high-risk of premature birth. To ensure treatment efficacy before delivery, the current practice is to administer steroids early to a woman considered at risk; however, neonatal benefit is lost after the seven-day treatment-to-delivery window. Over half of women who deliver before 34 weeks' gestation do not receive antenatal corticosteroids within this timeframe, but many still deliver prematurely; however, clinicians are reluctant to administer repeated courses of steroids due to concerns, among others, of impaired fetal growth. However, evidence is mounting regarding the optimal timing for steroids, including substantive benefits close to delivery, and the benefits of repeated courses if delivery has not occurred. Better targeted treatment is required to allow for maximum benefit; reducing unnecessary treatment in low-risk women, while targeting therapy in the high-risk cohort and offering repeat courses if the seven-day window is exceeded. Novel tools to aid prediction may help implement this strategy.

Trends in optimal, suboptimal, and questionably appropriate receipt of antenatal corticosteroid prophylaxis

OBJECTIVE

To conduct a population-based study to assess rates of optimal, suboptimal, and questionably appropriate administration of antenatal corticosteroid (betamethasone or dexamethasone) use.

METHODS

All live births in Nova Scotia, Canada, from 1988 to 2012 were included in the study. Temporal trends in optimal (proportion of live births at 24-34 weeks of gestation exposed to antenatal corticosteroids between 24 hours and 7 days before delivery), suboptimal (proportion of live births at 24-34 weeks of gestation exposed to antenatal corticosteroids less than 24 hours or more than 7 days before delivery), and questionably appropriate exposure to antenatal corticosteroids (proportion of live births 35 weeks of gestation or greater exposed to antenatal corticosteroids) were quantified using odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Among 246,459 live births between 1988 and 2012, 2.5% received a partial or a full course of antenatal corticosteroids. The rate of antenatal corticosteroid exposure for neonates born between 28 and 32 weeks of gestation increased from 39.5% in 1988-1992 to 79.3% in 2008-2012, whereas exposure for those born at 33-34 weeks of gestation increased from 14.3 to 49.7%. Optimal antenatal corticosteroid receipt increased from 10% in 1988 to 23% in 2012 (OR 2.7, 95% CI 1.6-4.5), suboptimal administration increased from 7 to 34% (OR 6.7, 95% CI 3.9-11.6), and questionably appropriate administration increased from 0.2% in 1988 to 1.7% in 2012 (OR 7.5, 95% CI 4.9-11.3). Of the women who received antenatal corticosteroids in 2012, 52% delivered at 35 weeks of gestation or greater.

CONCLUSION

Temporal increases in optimal exposure to antenatal corticosteroids have been matched by increases in suboptimal and questionably appropriate receipt of antenatal corticosteroids, highlighting the need for accurate preterm delivery prognostic models.