We have evaluated a cohort of women booked for antenatal care at University College London Hospitals. The uptake of screening was 64.4% and was significantly higher (73 versus 46%) in women who booked before 14 weeks. Of the women who booked before 14 weeks, 96.8% opted for the integrated test (IT). Overall, 5.3% failed to attend for the second blood test. The false-positive rate in the women who had the IT was 2.9%. All 11 cases of Down syndrome were detected prenatally. Our study is the first to evaluate implementation of the IT into routine clinical practice.