Welcome to Twins Trust twin growth charts. In twin pregnancies assessment of fetal growth is an essential component of antenatal care. The portal has been developed as an aid to clinicians caring for twin pregnancies and features downloadable customised twin growth charts as well as tools to help calculate centiles for estimate fetal weights. The data has been developed using almost 10,000 ultrasound examinations from more than 2,000 UK twin pregnancies and the aim is to provide safer evidence based care for twin pregnancies worldwide.