Prescribing patterns of antenatal corticosteroids in women with threatened preterm labor

ObjectiveTo assess the impact of cervical length (CL) measurement and fetal fibronectin testing (fFN) on the clinicians’ decision to prescribe antenatal corticosteroids (ACS) to women with symptoms of preterm labor.Study designThis is a secondary analysis of a prospective cohort study including women with symptoms of preterm labor and intact membranes between 24 and 34 weeks’ gestation. We compared the proportion prescribed and completed ACS courses, preterm delivery within seven days and median intervals from ACS to delivery in four groups: group 1 CL < 10 mm, group 2 CL 10–30 mm and positive fFN, group 3 CL 10–30 mm and negative fFN, group 4 CL > 30 mm.ResultsACS were prescribed to 63/65 (97%) women in group 1, 176/192 (91%) in group 2, 111/172 women (65%) in group 3 and 55/242 (23%) in group 4. In group 1, 42 (65%) women delivered within seven days, compared to 34 (18%) in group 2, 6 (3%) in group 3 and 3 (1%) in group 4. Median intervals between ACS and delivery were 6 days (IQR 3–61 days), 44 days (IQR 17–69 days), 53 days (IQR 37–77 days) and 66 days (IQR 43–78 days) in group 1, 2, 3 and 4 respectively.ConclusionACS were prescribed frequently to women with a CL of 10–30 mm and a negative fFN test or a CL > 30 mm. There is room for improvement in the prescription of ACS in these low risk women.