Conjoined twins represent a rare type of monoamniotic twins. Ultrasound assessment during the first trimester can facilitate the diagnosis, however further assessment by colour Doppler studies, 3D imaging, fetal echocardiography and fetal magnetic resonance imaging (MRI) is usually required in order to determine the specific fetal abnormalities and to guide appropriate pregnancy management. This case report presents a rare case of conjoined twins complicating a dichorionic-diamniotic triplet pregnancy, achieved after intracytoplasmic sperm injection (ICSI) and blastocyst transfer. A 44-year-old woman was referred for chorionicity determination to our Fetal Medicine Centre due to suspicion of conjoined twins in a triplet pregnancy. Ultrasound assessment at 11 weeks demonstrated a dichorionic triplet pregnancy which was also complicated by a rare type of conjoined twins (thoracoomphalopagus) and after a successful embryo reduction a neonate of 2200 g was delivered by caesarean section at term. The accurate diagnosis and early detection of conjoined twins by a fetal medicine specialist is crucial, especially as far as multiple pregnancies with three or more fetuses are concerned.
Keywords: ICSI; conjoined; triplet pregnancy; twins; ultrasound.