The present study investigated if acetyl salicylic acid (ASA) and terbutaline in combination increased the clinical pregnancy rate in patients undergoing in vitro fertilisation (IVF)/intra-cytoplasmic sperm injection (ICSI). A randomised controlled trial was designed, in which 167 patients were randomised to taking ASA for 9 weeks after embryo transfer and terbutaline around the time of embryo transfer as adjuvant medication. A total of 112 patients were randomised to no adjuvant medication. The clinical pregnancy rate per controlled ovarian hyperstimulation was 30.5% in the intervention group and 42.0% in the control group. This difference was not statistically significant, and we conclude that ASA and terbutaline in combination do not increase the clinical pregnancy rate after IVF/ICSI treatment.