Twin Growth Course
Twin Growth Course is organized by Institute For Advanced Medical Education (IAME)
Date of Release
Apr 24, 2006
Date of Most Recent Review
May 19, 2021
Expiration Date
May 19, 2024
Target Audience:
Physicians, sonographers and others who perform and/or interpret obstetrical ultrasound.
Accreditation:
The Institute for Advanced Medical Education is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.
The Institute for Advanced Medical Education designates this enduring material for a maximum of 1 AMA PRA Category 1 Credit™. Physicians should only claim credit commensurate with the extent of their participation in the activity.
These credits are accepted by the American Registry for Diagnostic Medical Sonography (ARDMS).
For information on applicability and acceptance of continuing education credit for this activity, please consult your professional licensing board or other credentialing organization.
Course Description:
Twin gestations normally occur once in every 80 to 90 live births. Approximately 30% of spontaneous twins are monozygotic. The rate of monozygotic splitting is higher after artificial reproductive techniques
• The timing of division in monozygotic twins determines chorionicity and amnionicity (Table I)
• As noted in Table I, approximately 30% of monozygotic twins are dichorionic/diamniotic.
While a first trimester ultrasound can reliably determine chorionicity and amnionicity, it cannot assess zygosity. A transvaginal ultrasound examination can visualize a corpus luteum in over 95% of early 1st trimester pregnancies. Tong et al 3 have proposed determining zygosity by evaluating the ovaries for corpus lutea - one corpus luteum in monozygotic twins; and two corpus lutea in dizygotic twins. Additional studies are required to test the accuracy of this technique.
Course Objectives:
After completing this course, the participant should be able to:
• Describe the etiology of and how to determine chorionicity and amnionicity of twin pregnancy.
• Recognize patterns of growth discordancy in monochorionic and dichorionic twins.
• Improve the outcome of twin pregnancy through the use of ultrasound to recognize the 'at risk' population.
Additional details will be posted as soon as information is available.