The effect of tocolytic agents (indomethacin and terbutaline) on fetal breathing and body movements: a prospective, randomized, double-blind, placebo-controlled clinical trial.
OBJECTIVE
The null hypothesis of this study is that maternal administration of indomethacin or terbutaline will not affect fetal breathing and body movements.


METHODS
Thirty patients with a low-risk pregnancy, gestational age 26 to 32 weeks, and no signs of preterm labor were randomly assigned to receive either terbutaline (5 mg), indomethacin (50 mg), or a placebo. Ultrasonographic evaluation of fetal breathing and body movements was performed for 1 hour before and 1 hour after treatment. The total amount of time of fetal breathing and body movements in each group was subject to statistical analysis that included analysis of variance and covariance and a multiple comparison procedure.


RESULTS
Indomethacin increased fetal breathing from 20.8 +/- 13.1 minutes to 42.2 +/- 14.8 minutes (p < 0.01), whereas terbutaline increased fetal breathing movements from 19.8 +/- 9.0 minutes to 35.2 +/- 12.4 minutes (p < 0.01). No significant treatment effect was detected on fetal body movements.


CONCLUSIONS
Between 26 and 32 weeks' gestation, a single dosage of indomethacin or terbutaline increases fetal breathing movements by 103% and 78%, respectively.
Hallak
M
M
Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas.
Moise
K
K
Lira
N
N
Dorman
K F
KF
Smith
E O
EO
Cotton
D B
DB
D004311:Double-Blind Method; D005260:Female; D005324:Fetal Movement / Q000187:drug effects*; D005333:Fetus / Q000187:drug effects*; D006801:Humans; D007213:Indomethacin / Q000494:pharmacology*; D010919:Placebos; D011247:Pregnancy; D011446:Prospective Studies; D012119:Respiration / Q000187:drug effects*; D013726:Terbutaline / Q000494:pharmacology*; D015149:Tocolytic Agents / Q000494:pharmacology*
D010919:Placebos; D015149:Tocolytic Agents; D013726:Terbutaline; D007213:Indomethacin