Multiple Births

Multiple Births

A multiple birth occurs when more than one fetus is carried to term in a single pregnancy. Different names for multiple births are used, depending on the number of offspring. Common multiples are two and three, known as twins and triplets, respectively. These and other multiple births occur to varying degrees in most animal species, although the term is most applicable to placental species.

Multiple birth siblings are either monozygotic or polyzygotic. The former result from a single fertilized egg or zygote splitting into two or more embryos, each carrying the same genetic material (genes). Siblings created from one egg are commonly called identical. Since identical multiples share the same genetic material, they are always the same sex. Polyzygotic (or fraternal) multiples instead result from multiple ova being ripened and released in the same menstrual cycle by a woman's ovaries, which are then fertilized to grow into multiples no more genetically alike than ordinary full siblings, sharing 50% of their genetic material. Multiples called "dizygotic" represent multiples from two eggs specifically. For example, a set of triplets may be composed of identical twins from one egg and a third non-identical sibling from a second egg.

The most common form of multiple births for humans is twins. Many placental species give birth to multiples as a matter of course, with the resulting group called a litter.

Read more about Multiple BirthsTerminology, Higher Order Multiples, Human Multiple Births, Cultural Aspects

Other articles related to "multiple birth, multiple births, multiples, multiple, births, birth":

Multiple Birth
... A multiple birth occurs when more than one fetus is carried to term in a single pregnancy ... Different names for multiple births are used, depending on the number of offspring ... Common multiples are two and three, known as twins and triplets ...
Human Fertilisation And Embryology Authority - Policy Decisions
... the HFEA decided on a policy to reduce multiple births from fertility treatment ... This forms part of a wider national strategy to reduce the risk of multiple births from fertility treatment involving professional bodies, patient groups and NHS-funding bodies ... Multiple pregnancy is the single biggest risk to patients and children born as a result of fertility treatment ...
Kodinhi - Culture and Demographics - Twin Births
... survey done by locals found an unusually large number of twin births in the region ... Though initial estimates put the instance of multiple births at 100 pairs, follow-up surveys found the figure to be closer to 204 pairs (408 individuals) of twins, and two sets ... Kodinhi married off to far away places are also known to give birth to twins ...
Multiple Births - Cultural Aspects
... Certain cultures consider multiple births a portent of either good or evil ... legend of the twin brothers who founded the city (Romulus and Remus) made the birth of twin boys a blessing, while twin girls were seen as an unlucky burden, since both would have to ... European chivalric romances, such as Marie de France's Le Fresne, a woman cites a multiple birth (often to a lower-class woman) as proof of adultery on her part while this may reflect a ...

Famous quotes containing the words births and/or multiple:

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