Jackie Kousma

1
Twin Studies

• By
• Jackie Kousma
• Brandi Butler
• Kyle Wilson
• Andrew Geis

2
Fraternal Twins

• Fraternal twins are the result when two different
  eggs are fertilized by two different sperm.
• This leads to the development of two separate
  placentas.

3
Fraternal Twins
Fraternal twins are more common than
identical twins and account for about 2/3 of twin
pregnancies. Are different sexes and have
different blood types
4
Identical Twins

• Identical twins develop when a fertilized egg
  splits.
• Depending on when the split occurs will determine
  if the twins share placenta, or if they each
  develop their own.
• The later the split occurs the more likely the
  twins will share one placenta.

5
Siamese Twins

• Conjoined twins are monozygotic multiples that do
  not fully separate from each other due to the
  incomplete division of the fertilized ovum.
• The individuals will be connected at certain
  points of the body, and may share tissue, organs
  or limbs.
• About 1 in 200 sets of identical twins are born
  conjoined.

6
Types of Siamese Twins

• Upper trunk and head cephalopagus
• Head craniopagus
• Brain, head, chest ephololthoracopagus
• Trunk omphalopagus
• Rear end pygopagus
• Chest thoracopagus
• Lower body (side/side) parapagus
• Lower body (front/back) ischiopagus

7
Prognosis for Conjoined Twins

• Depends on how the twins are connected
• 40-60 are still born
• 35 survive 24 hours or less
• Some conjoined twins live successful lives
  despite the unique challenges they face.
• Others are plagued by medical complications due
  to shared organs and vital systems.

8
Separation

• There have been approximately 200 attempted
  surgical separations of conjoined twins.
• ¾ of the procedures since 1950 have resulted in
  one or both of the twins surviving.

9
Twins Separated At Birth

• Still look alike
• Have similar hobbies
• Name pets similar names
• Answer questions alike

10
Famous Twins