Human reproduction
Human reproduction is the process by which children are conceived and born. In order for human reproduction to occur under normal circumstances, male and female must engage in sexual intercourse. Exceptionally, reproduction may take place without intercourse via procedures such as in vitro fertilization.
Spiritual aspects
Human reproduction serves partly to create new human beings but with the use of contraception is mainly used as a pleasurable activity, until such time a couple feel ready to conceive a child.
There are many silly religious beliefs, even within Christianity, on the origin of the soul that accompanies a new human being. Some believe portions of the souls of the parents combine to form the new soul. Some believe a free-floating soul becomes trapped within the body. Some believe a soul is created with the fusion of the gametes, in a meta-chemical process. Believers of reincarnation would say that the soul of a previously deceased person or animal (this religion believes animals have souls too) would enter the new body, so that there is a spiritual memory of the previous life.
Biological aspects
The ultimate act of intimacy serves to unite the male and female gametes, the sperm and egg, respectively. These gametes carry just one half of the genetic material (chromosomes) from each parent, and when they combine the new embryo contains a full set of chromosomes. The process of the gametes combining is called fertilization, and takes place inside the woman's body, in the Fallopian tubes or uterus. The embryo then attaches itself to the uterine lining, and is nourished by the placenta (which in turn receives its nourishment from the mother's body) while it develops. This development takes roughly nine months (see Naegele's Rule).
At the end of this process of protected development, what was once an embryo is now born as a new baby. Human babies are relatively helpless, and depend on the care and love of both parents in order to survive to maturity themselves.
Humans are not yet able to reproduce alone by budding, parthenogenesis, or self-cloning as some species are capable of. In addition, human gender is fixed at conception, unlike some species'; females are not able to become male or vice versa to deal with homogeneous populations of one gender.
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