Does antenatal betamethasone have negative effects on fetal activities and hemodynamics in cases of preeclampsia without severe features? A prospective, placebo-controlled, randomized study

AIM

To evaluate whether antenatal betamethasone affects the fetal biophysical profile (BPP) and Doppler indices of umbilical and middle cerebral arteries (MCAs) in cases of preeclampsia without severe features.

MATERIALS AND METHODS

Forty singleton preeclamptic pregnancies without severe features at gestational ages of 28-34 weeks were randomly divided into two groups of 20 patients: betamethasone and control groups. Patients in the betamethasone group were administered two consecutive doses of 12 mg betamethasone intramuscularly, 24 h apart, and patients in the control group were administered the same volume of saline as a placebo. All participants were evaluated before (0 h) and at hours 24, 48, and 72 of betamethasone/placebo administration using BPP scoring and umbilical and MCA Doppler examinations.

RESULTS

Total BPP scores were significantly lower in the betamethasone group across the three time points during the follow-up period (p < 0.001). None of the Doppler indices differed significantly between the groups (p > 0.05).

CONCLUSION

Antenatal betamethasone negatively affects fetal BPP score parameters, including the non-stress test, fetal body and breathing movements, without affecting vascular indices of umbilical arteries and MCAs. Clinician awareness of this transient drug-induced effect might be valuable for preventing iatrogenic preterm delivery for fetuses in preeclamptic pregnancies without severe features.

Glucocorticoid regulation of surfactant components in immature lambs

To assess effects of dose and duration of glucocorticoid exposure on maturation of the fetal lung, we administered single or multiple doses of betamethasone (0.5 mg/kg im) to pregnant sheep for 2 or 21 days before preterm delivery at 125 days of gestation. Lung function (compliance, lung volume at 40 cmH2O pressure, and ventilatory efficiency index) was increased after two to four weekly doses of glucocorticoid (2.5- to 4-fold increase) and after 48 h of exposure (1.4- to 2.3-fold). Total protein of lavage fluid decreased similarly with three doses, four doses, and 48 h of treatment. In lambs with long-term exposure to betamethasone, there was a similar, dose-dependent increase in concentrations of saturated phosphatidylcholine and surfactant proteins A (SP-A) and B (SP-B) (maximal 2- to 3-fold in tissue and 10- to 15-fold in lavage fluid). Levels of SP-A and SP-B were closely correlated in lavage fluid. In animals treated for 48 h, only tissue SP-B was increased (2.7-fold). We conclude that 48 h of glucocorticoid treatment improves lung function in the premature lamb without a detectable increase in lavage surfactant components and that longer exposure to antenatal glucocorticoid increases surfactant lipid and proteins in a coordinated fashion. The enhanced response with repetitive dosing indicates that the process of glucocorticoid-induced lung maturation is either reversible and/or gestational age dependent.