This study involves a minimal risk intervention, as it is a pilot cluster RCT of the implementation of an EMR alert (regarding progesterone prescription for care of pregnant women at risk of preterm birth, a practice considered standard of care in many guidelines). The Hamilton Integrated Research Ethics Board (HiREB) has approved for clinics to be randomized and all eligible women at intervention clinics to receive the intervention (and all eligible women at control clinics to receive routine prenatal care). As this is a minimal risk intervention and a pilot cluster RCT, individual participant consent is not required. Rather, informed, written consent of the clinics and care providers at the clinics will be obtained for their participation in this study and the use of their questionnaire and structured interview responses. There will be no interim analysis given the minimal-risk nature of the intervention, and the pilot nature of the study, and hence investigators will not have a Data Safety Monitoring Board (DSMB), but will have a Steering Committee.