Their hair whorls will turn in opposite directions. Mirror twins are identical twins that scientists believe split later in the embryonic stage (Wolner 103). When the cluster of cells do finally spit, there is already a formed right side and formed left side with one twin developing from each side. There are even medical examples where one mirror image twin has internal organs on the right side of the body and the other on the left (Wolner 104). .
Multiple gestation is a medical term that refers to a women who is pregnant with twins, triplets, or other higher- order multiple pregnancies (Segal 97). This will occur in slightly less than two percent of all pregnancies (Segal 97). Within the category of multiple gestation, twin births are by far the most common, accounting for ninety-five percent of all multiple pregnancies.
Triplets are a unique type of multiple births. Triplets are born at the same time of the same mother. One set of triplets is born about every 9,216 births (Vaughan16). Fraternal triplets are born from three egg cells. Identical triplets are born from one egg cell that divided into three separate eggs. Triplets may also include an identical pair plus a third fraternal.
Quadruplets are four children born to a mother at one time. They occur more often than quintuplets, but less often then triplets. Quadruplets are born once in every 884,763 births (Wright 19). Identical quadruplets are born from the cell mass of a single egg that became separated. There are also four possible combinations of identical and fraternal quadruplets. That happens when some are in one cell mass and the other one or two have their own separate cell mass. There are also fraternal quadruplets that have their own egg cell.
Quintuplets are five babies born to the same mother at one time. They are estimated to occur once in every eighty-five million natural births (Wright 26). It is very common for all of them not to survive.