(HealthDay)—Exposure to repeat doses of antenatal betamethasone is not associated with alterations in bone mass in mid-childhood compared with a single course of glucocorticoids, according to a study published online April 7 in Pediatrics.

Christopher J.D. McKinlay, Ph.D., from the University of Auckland in New Zealand, and colleagues randomized women at risk for to a single dose of betamethasone or placebo at seven or more days after an initial course of glucocorticoids, repeated each week that they remained at risk. Children were assessed with whole-body dual-energy radiograph absorption at a corrected age of 6 to 8 years. One hundred eighty-five of 212 eligible childhood survivors were assessed (91 repeat betamethasone group; 94 ).

The researchers found that whole-body bone mineral content was similar for children exposed to repeat antenatal betamethasone and those exposed to placebo (553 and 567 g, respectively; geometric mean ratio, 0.99; 95 percent confidence interval, 0.94 to 1.03; P = 0.55), as was bone area (832 and 822 cm², respectively; geometric mean ratio, 0.99; 95 percent confidence interval, 0.92 to 1.07; P = 0.75).

"Exposure to repeat doses of antenatal betamethasone compared with a single course of glucocorticoids does not alter in mid-childhood," the authors write.