Fraternal vs. Identical Twins: How to Tell the Difference

Determining the possibility of fraternal twins

One well known method is to identify the placenta during pregnancy. In case of fraternal twins, there are two placentas and each baby has its own amniotic sac. This would be determined via an ultrasound scan.

Determining the presence of identical twins

There are more characteristics involved in determining whether they are identical as shown in the list below.

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Identical twin determination factors:

- Look at the sex. If both babies are the same sex, they may be identical. If they are different sexes, they are fraternal.

- Compare physical appearance. Identical twins often look very much alike, sharing similar features such as eye color, hair color, and facial structure.

- Check the fingerprints. Identical twins have identical fingerprints.

- Review medical history. Identical twins are more likely to share certain medical conditions, such as heart defects, autism, and diabetes.

- Perform a DNA test. A DNA test can definitively determine whether twins are identical or fraternal.