Twins and Multiple Births There are two types of twins, and they occur in two different ways… Identical twins Fraternal twins • identical • not identical Click here to learn more about twins • formed when one fertilized egg divides • two eggs are fertilized at the same time Chances of multiple births Twins: 1 in 90 Triplets: 1 in 8100 Quadruplets: 1 in 729,000

Multiple Births first set of octuplets born alive, in Houston TX, in 1998 identical quadruplets triplets van Tol quintuplets McCaughey septuplets Gosselin twins & sextuplets news on multiple births

Conjoined twins Conjoined twins are identical twins whose bodies are joined in utero. A rare phenomenon, the occurrence is estimated to range from 1 in 50,000 births to 1 in 200,000 births. Approximately half are stillborn, and a smaller fraction of pairs born alive have abnormalities that do not allow them to survive. The overall survival rate for conjoined twins is approximately 25%. Some conjoined twins can be separated surgically, and some cannot.

Perhaps the most famous pair of conjoined twins was Chang and Eng Bunker (1811–1874), Chinese brothers born in Siam, now Thailand. They traveled with P.T. Barnum's circus for many years and were billed as the Siamese Twins. The brothers married two sisters, Adelaide and Sarah Yates, who were neither twins nor connected themselves. The couples were married in 1843 and produced 21 children between the two families.

Some Modern-Day Conjoined Twins Abby & Brittany video facts link

Animals can be born conjoined too!

Biracial Twins Twins-One Black, One Whi#C0AA03 Biracial Twin Sisters.webloc

Vanishing Twin Syndrome when one of a set of twin/multiple fetuses disappears in the uterus during pregnancy. This is the result of a miscarriage of one twin/multiple. The fetal tissue is absorbed by the other twin/multiple, placenta or the mother. “Disappearing” or miscarried twin Surviving twin Vanishing Twin Syndrome #C0BEC6