5 types of twins

Cecil's Columns/Staff Reports
1

I read about a way for there to be five types of twins based on conception and developement.

  1. Indentical
  2. Fraternal
  3. Siamese
  4. a rare case when the mother ovulates after conception. The new egg is fertilized about a month or more after the first.
  5. The extremely rare case of twins by different fathers. This happens when the last case occurs but the second egg is fertilized by a different man’s sperm.

I am sure the mother will have a lot of explaining to do once the kids get to grade school.

2

Since we don’t know exactly what kind of answer the writers of Trivial Pursuit were thinking of, it will be hard to tell whether your explanation or Cecil’s is more accurate.

See second part of the 7 January 2000 column.

… Plus: are there five kinds of twins? (07-Jan-2000)

3

There was already a thread on this topic. See
http://www.straightdope.com/ubb/Forum1/HTML/000431.html