Kwa Kiswahili ni vigumu kueleza ila mayai ya mwanamke na mbegu ya mwanamume inaweza kuwekwa kwenye mfuko wa uzazi wa mwanamke mwingine (surrogate mother) ili akuzalie mtoto.
Mara nyingi watu wanatafuta "surrogate mother" kama mke hawezi kuzaa.
Hii pia ni biashara kubwa. Wanawake wanalipwa $5000-$10000 kubeba mimba ya watu kwa nchi ambazo hazikatazi mwanamke awe "surrogate mother".
Surrogate Mother
A woman who bears a child on behalf of another woman, either from her own egg fertilized by the other woman's partner, or from the implantation in her uterus of a fertilized egg from the other woman.
A woman who carries someone else's baby contributes very little, if any, DNA to the child. This is because the child already has its DNA from its mom and dad. Also, the baby's own blood passes through its body not the blood of its surrogate mom.
However, there is a possibility that some DNA could be transferred from the woman to the fetus that she is carrying. And vice versa, from the child to the mother.
Remember a child's DNA comes from two places. Half comes from its mother and half from its father.
A baby forms from an egg (from the mom) that is fertilized by a sperm (of the dad). The fertilized egg divides and divides to eventually become the child.
In addition to forming the child, it also forms something called the placenta.
The placenta is attached to the inside of the uterus of the mother. The placenta then connects to the baby by its umbilical cord.
The placenta is a gatekeeper between the mother and the child. It is very important because it only lets certain things pass through it. The placenta is what prevents much DNA from passing between the mother and the child.
The placenta allows nutrients that the baby needs to pass from the mother to the baby. The placenta also lets waste that the child doesn't need go back through to the mother. But the placenta doesn't let blood or other cells from the mother or child pass through.
This means that in theory, no DNA gets through either, since DNA is inside of cells. For the most part, the surrogate mom's DNA stays on one side of the barrier and the baby's on the other.
Of course, nothing in life is completely perfect. And that includes the placenta.
Cells can sometimes get through the placenta. This can happen in both directions from the mother into the child, and from the child into the mother.
It is a bit more common for DNA from the child to get into the mother. But cells from the mother can get into the child too carrying along the DNA of the mother.
At one time this was thought to be very rare. But, some recent studies have found a few cells from the mother pass into the child in around 40% of pregnancies.
The bottom line is that once an egg is fertilized, the woman carrying the fertilized egg does not contribute a significant amount of DNA to the fetus.
source:genetics.thetech.org
