RT Journal Article SR Electronic T1 Oral β-agonists probably do not reduce the incidence of preterm delivery JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 12 OP 12 DO 10.1136/ebm.1995.1.12 VO 1 IS 1 YR 1995 UL http://ebm.bmj.com/content/1/1/12.abstract AB