the ovariectomized , oestrogen-treated , late pregnant rat has been used to compare the ability of two calcium antagonists , diltiazem and nifedipine , with an agonist at beta-adrenoceptors , salbutamol , to prevent the development of uterine contractions , prolong gestation and maintain fetal survival in utero .
C0014939
oestrogen
C0032961
gestation