A 40-year-old member asked:
Heterochromia in one identical twin, not the other. are they fraternal?
1 doctor answer • 2 doctors weighed in
Maternal-Fetal Medicine 27 years experience
Not necessarily.: Identical vs. Fraternal twins are archaic terms that no longer apply to the modern perinatal terminology., however are still generally true and understandable to lay people. The color of eyes is not the determining factor in zygocity or chorionicity of twins - check prenatal records and placental pathology!
5.7k viewsReviewed >2 years ago
A 45-year-old member asked:
How do I know if I am having identical or fraternal twins?
2 doctor answers • 9 doctors weighed in
A Verified Doctoranswered
31 years experience
Depends: You can determine it based on ultrasound if there is only one placenta. However, often times you need to have babies tested after they are born. Even twins that "look" identical may not actually be identical.
6.3k viewsReviewed >2 years ago
A 35-year-old member asked:
Are fraternal or identical twins more common?
2 doctor answers • 2 doctors weighed in
Specializes in Obstetrics and Gynecology
Yes: Fraternal twins are 3 times as frequent as identical. Fraternal twins happen when there is double ovulation and 2 eggs get fertilized. They are the type of twins that run in families. Identical twins come from 1 fertilized egg which separate in early gestation. Depending on when they separate, the babies can be in 2 distinct sac (di/di), 2 sacs within a shared sac (mono/di) or 1 sac (mono/mono).
6.6k viewsAnswered >2 years ago
Last updated Sep 15, 2017
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