how a woman deliver more than 3 offsprings at same time
Answers
If it splits completely into two separate groups of cells very early in this division then identical twin zygotes are formed. Cell division continues until each zygote has become a ball of cells which implants (attaches and embeds) into the lining of the womb and becomes an embryo. Each embryo will eventually become a baby.
As the balls of cells implant into the wall of the womb (uterus), they meet up with some specialized cells from the mother's womb and, between them, start to form the afterbirth (placenta). The placenta is crucial to the pregnancy - it is the place where your body 'meets' your baby directly to pass across the nutrients your baby needs to grow. Although your blood and your baby's blood do not actually mix with one another (if you don't share the same circulation), in the placenta your blood and your baby's blood come close together.
The ball of cells now starts to form distinct areas, including a central group of cells (which will form your baby) and the outer cells which will form the amniotic sac (membranes). The membranes have two layers - an inner lining (called the amnion) and an outer lining (called the chorion). Multiple pregnancies occur in nature. In some cases, the woman produces more than one egg (ovulates). In others, there is just one egg fertilized but it splits into two zygotes.
Multiple pregnancies are more likely after fertility treatments particularly assisted reproductive techniques such as in vitro fertilization (IVF). This is because it is usual for more than one embryo to be transferred to the womb (uterus). In the early days of IVF doctors transferred large numbers of embryos into the womb, as many were lost. However, this resulted in a few women becoming pregnant with very large numbers of babies (in some cases six or more), making the chance of each baby's survival very small and the risks to the health of the mother very large. There is now a strict restriction on the number of embryos put into the womb after fertility treatment.
A multiple birth is the culmination of one multiple pregnancy, wherein the mother delivers two or more offspring. A term most applicable to placental species, multiple births occur in most kinds of mammals, with varying frequencies. Such births are often named according to the number of offspring, as in twins and triplets. In non-humans, the whole group may also be referred to as a litter, and multiple births may be more common than single births. Multiple births in humans are the exception and can be exceptionally rare in the largest mammals.
Each fertilized egg (zygote) may produce a single embryo, or it may split into two or more embryos, each carrying the same genetic material. Fetuses resulting from different zygotes are called fraternal and share only 50% of their genetic material, as ordinary full siblings from separate births do. Fetuses resulting from the same zygote share 100% of their genetic material and hence are called identical. Identical twins are always the same sex, except in cases of Klinefelter syndrome (also known as XXY syndrome and 47,XXY syndrome).
A multiple pregnancy may be the result of the fertilization of a single egg that then splits to create identical fetuses, or it may be the result of the fertilization of multiple eggs that create fraternal fetuses, or it may be a combination of these two. A multiple pregnancy from a single zygote is called monozygotic, from two zygotes is called dizygotic, or from three or more zygotes is called polyzygotic.
Similarly, the siblings themselves from a multiple birth may be referred to as monozygotic if they are identical or as polyzygotic if they are fraternal.