OBJECTIVE: To evaluate the total number of inter-twin contacts between monochorionic diamniotic (MD) and dichorionic diamniotic (DD) twins using four-dimensional (4D) sonography late in the first trimester of pregnancy. METHOD: Six MD and 8 DD pregnancies were studied for 30 minutes with 4D sonography at 10-11 and 12-13 weeks of gestation. A total of 10 types of inter-twin contact was evaluated. RESULTS: There was a significant difference in the total number of all contacts between MD and DD twins at the 10-11 weeks of gestation (P<0.05). There was also a significant difference in the total number of contacts between 10-11 and 12-13 weeks of gestation in DD twins (P<0.05). CONCLUSION: Four-dimensional sonography provides a means of evaluating inter-twin contact in the first trimester of pregnancy and could be an accurate and reliable tool in studies of inter-twin behavior. Copyright 2009 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
OBJECTIVE: To evaluate the total number of inter-twin contacts between monochorionic diamniotic (MD) and dichorionic diamniotic (DD) twins using four-dimensional (4D) sonography late in the first trimester of pregnancy. METHOD: Six MD and 8 DD pregnancies were studied for 30 minutes with 4D sonography at 10-11 and 12-13 weeks of gestation. A total of 10 types of inter-twin contact was evaluated. RESULTS: There was a significant difference in the total number of all contacts between MD and DD twins at the 10-11 weeks of gestation (P<0.05). There was also a significant difference in the total number of contacts between 10-11 and 12-13 weeks of gestation in DD twins (P<0.05). CONCLUSION: Four-dimensional sonography provides a means of evaluating inter-twin contact in the first trimester of pregnancy and could be an accurate and reliable tool in studies of inter-twin behavior. Copyright 2009 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.