Clinical indication and timing of antenatal corticosteroid administration at a single centre

Abstract

Objective To determine how well antenatal corticosteroids (ACS) were timed, based on the indication for administration for women delivering preterm.Design Retrospective cohort study.Setting Tertiary medical centre.Population Six hundred and thirty women who had singleton preterm births between 24 and 34 weeks' gestational age.Methods Charts from 2006 to 2011 were reviewed for indications for ACS administration, which included premature rupture of membranes, threatened preterm labour, risk factors for spontaneous preterm birth such as short ultrasound cervical length, positive fetal fibronectin, and hypertensive disorders of pregnancy. Charts were reviewed for timing of ACS administration in relation to delivery.Main outcome measures The primary outcome was optimal timing, defined as administration of ACS ≥24 hours to ≤7 days prior to delivery.Results Of 630 women who delivered preterm, 589 (93%) received ACS prior to delivery. ACS timing was optimal in 40% (238 of 589) of cases. Women with hypertensive disorders were most likely to have steroids optimally timed (62%). Asymptomatic women at increased risk for preterm delivery were less likely to receive optimally timed ACS (12%). The majority of women who received steroids >2 weeks prior to delivery (57%) received a second course.Conclusion A majority of women who delivered preterm did not receive optimally timed ACS. Diagnostic tools that identified women at risk for preterm birth were not able to identify patients for appropriate steroid timing. Given the range of clinical scenarios in which patients are at increased risk for preterm delivery, further research is needed to assist clinicians in optimising steroid administration.

Antenatal corticosteroids: a retrospective cohort study on timing, indications and neonatal outcome

“…The timing of ACS influences the likelihood of benefit from treatment. In this study, optimal timing of ACS was achieved in 40.8% of the women, a rate comparable to others’ . The timing of ACS varied greatly depending on the obstetric indication for treatment; women with PPROM or vaginal bleeding had a median ACS delivery interval of more than seven days, significantly longer than women treated for other indications.…”

“…The ACS delivery interval varies and the proportion of optimally timed ACS (>24 h and ≤7 days before delivery) is generally poor . Previous studies have confirmed that women with PPROM have a longer ACS delivery interval compared with women with other obsteric indications .…”

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

“…Previous studies have reported variable ACS administration rates among live births below 35 weeks gestation of between 35–93% . While not always clear as to whether such administration relates to a partial or complete single course of ACS as evaluated in this study, studies reporting optimal administration have uniformly demonstrated low rates of 25–50% of livebirths, More recently, interest has grown in determining what defines optimal ACS administration. While often regarded and studied as administration occurring more than 24 h but less than seven days following the first dose, there is still evidence that ACS use reduces neonatal death even when birth occurs within 24 h of the first dose .…”

“…It is positive that iatrogenic preterm birth was associated with the highest rates of optimal ACS timing, but this is still achieved in less than half of the women. Such findings are in agreement with previous studies, but raise questions as to what degree optimal administration rates can be improved. The unpredictable occurrence and varying clinical courses with regard to when delivery occurs spontaneously or is medically indicated across various obstetric complications make optimal ACS administration a challenge, with future investigations needed to better determine optimal steroid administration strategies.…”

“…Conversely, some women will unexpectedly give birth in less than 24 hours, with administration of ACS in this setting still considered advantageous . Recent studies have demonstrated that while a large proportion of women receive ACS prior to preterm birth, suboptimal timing (administration <24 h or ≥ seven days prior to delivery) of such administration occurs in a majority . Such difficulties in optimal timing of administration have led to investigations around the role of repeat ACS, for women who remain at risk of preterm birth seven days or more following their initial course .…”