How Twins Come About

Twins are very common amongst us; just the taught of two identical or unidentical individuals being born as twins is a quite interesting and mind blowing. But how really are twins formed. There are many kinds of multiple births some of which are fraternal twins, identical twins, Siamese twins etc. Fraternal Twins This result from the fertilization of two ova (eggs) released at the same time from the two ovaries by different sperms. Since the different sperms fused with the different ova, it is possible to have a boy and a girl, two boys or two girls. They twins do not look alike they are also called heterozygous twins or siblings. Identical Twins (homozygous twins): This results from the division of a single sperm, which develop into separate embryos. Such children are genetically identical and look very alike. They are always of the same sex. Their sources of variations are due to environmental condition and genetic mutation. Siamese Twins These are identical twins that did not separate up completely during development. The resulting children will be joined together and may share vital organs. These children normally die but recent medical techniques have been used to separate some successfully at birth. The separation is done by surgical operation. The first country to record Siamese twins is SIAM and this type of twins was then named after the country, thus the name Siamese twins. In Ghana, there are only two cases that have been successfully separated and the two had survived. This took place at korle-bu teaching hospital in the year 2000 and Komfo Anokye Teaching Hospital in the year 2001. Some other multiple births Apart from twins, other multiple births such as triplets, quadruplets etc are also possible but are not common in humans. Triplets may result from the release of three ova(eggs) at the same time and each is fertilized by different sperms. These types of triplets are non-identical. However, a single fertilized ovule (egg) can be divided into three and each develops to form a separate embryo. These triplets are very identical like identical twins. Quadruplets are also produced in a similar manner in this case, either four ova (eggs) are released by the ovaries at the same time or a single fertilized ovule is divided into four ova of which they develop to form four embryos.