Can you imagine doing a DNA test to be able to enroll your newborn children in the Civil Registry and find out that they have two different parents? Well, that's what happened to a couple from Xiamen, China, where it is mandatory to present a paternity test to prove that the children are theirs.
So the husband discovered that one of the babies was not his and that his wife had cheated on him. A strange case of dizygotic twins (known as twins), but possible. It is called heteroparental superfecundation, and consists of the fertilization of two or more ovules by sperm from different sexual acts, in a short period of time.
Hepatic superfecundation and superfecundation
Superfetation is a rare case of twins, of which only 11 cases are known in the world.
The first human superfetation report was published by Oskar Föderl in 1932, as explained in Xataka. It consists in the successful fertilization of an ovum released during pregnancy, and what results in the conception of twins of different gestational ages.
In Babies and more: Superfeeding: getting pregnant during pregnancyBut how can it be possible? It turns out that the usual thing is that when there is conception, the woman's reproductive system stops producing eggs. But very rarely the menstrual cycle repeats and a new egg is released while an embryo already exists. When that egg is fertilized (something even more strange), superfetation occurs, two embryos of different gestational ages.
These are non-identical or dizygotic twins (known as twins), as they result from the fertilization of two separate ovules, each with a different sperm, and develop in the uterus at the same time. They can be the same sex or different sexes and are no more similar than any brother or sister, despite being born together.
In Babies and more Twins and twins, are they the same? Because to be identical or monozygotic twins they should be born from a single ovule, fertilized by a single sperm, which divides and forms two babies. These brothers are of the same sex and share the same genes and physical characteristics.
And if in addition, as in the case of the Chinese couple, the ovules are fertilized by two sperm from two different men, we talk about heteroparental multiple fertilization.
In Babies and more Twins of different parents? If possibleThe situation is as follows: the woman has sex with a man and one of her eggs is fertilized by a sperm. In the same cycle he returns to ovulate and has sex with another man. Then, one of his sperm fertilizes a woman's second egg. There is a pregnancy of twins of different parents, who share the mother's womb.
This rare possibility only occurs in one of every 13,000 fertilizations, since women must have sex with different men within a maximum period of five days. But still, we have already seen that it is possible, because DNA doesn't cheat.
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