By: Hans Müller E.
Birth control is a part of strategical reproduction of animals. it can be clasified as; abstinence of intercourse, abortion, and infanticide. this can be foun in many societies human and nin human. Cases such as the bobcat that when doesnt finds enough food produces only one or two kittens instead of the usual three.
Contraception and birth control
Contraception is the use of devices or methods which act against conception (fertilization of an egg). other birth control methods prevent the developing of an egg to a baby. There are lots of birth control methods; some prevent the sperm to reach to the ovaries, other interfere with the reproductive cycle, or some prevent implantation ore ovulation, etc. Those different methods act using phhisical or chemical manipulation as well as behavioural manipulation.
Though each birth control method has advantages and disadvantages, birth control gives the human the abilitie to control the birth rate which by some experts can make a great difference on the future of our society´s development and survival since our population has grown exponentially in the las few centuries and a high birth rate in the future could be the triggery for the worlds starvation.
Chemical manipulation:
takes the form usually of pills. this pills contain synthetic oestrogen or progesterone. this stops the secrtion of several substances so taht neither follicule development nor ovulation occurs.
Increasing fertility
As we have the ability of controling birth we also have the opportunitie of increasing fertility using various methods such as artificial insemination, fertility drugs, and in vitro fertilisation.
Artificial insemination consists on using the sperm of an anonymous donor and insert it in the womans cervix.
Fertility drugs are basically chemicals that stimulate ovulation.
In vitro fertilisation the fertilisation of the eggs outside of the mothers body which then are artificially implanted in the uterus.
Paradoxically there are scientist that also promote the fertility improvement as the salvation for the future because it has been dicovered that pollutants have a negative effec with the males fertility and this improovements have proven a relief for the far future reproduction.
Birth control methods: (classified in 5 different categories)
Barriers:
Condoms:
Male condom: A thin latex sheath worn over the erect penis; at ejculation semen collects in the tip
Femle condom: a thin latex sheath with two elasticated rings; one is inserted into the vagina the other remains outside.
advantages: offer some protection against STD´s; no serious side effects reliable and easy to obtain.
disadvantages: can break or leak; cannot be used spontaneously; may lessen enjoyment of intercourse.
comments: protection improved if combined with spermicide; give protection agains STD´s.
Hormone manipulation:
"Morning after pill": contains high levels of oestrogen to prevent implantation.
advantages: can be used after rather than before intercourse.
disadvantages: high dose of oestrogen can produce unpleasant side-effects.
comments: not suitable for regular use.
Behavioural manipulation.
Withrawal: removal of penis before ejaculation
advantages: no cost
disadvantages: difficult to do; unreliable.
no comments
Surgical:
Vasectomy: vasa differentia of male cut and tued off to prevent passage of sperm to the penis.
advantages: a single operation gives a permanent effect; high reliability
disadvantages: may be irreversible
no comments
Other:
Intrauterine device: plastic or copper device that prevents implantation
advantages: allows sexual intercourse to be spontaneous.
disadvantages: can cause discomfort and can be displaced.
comments: requires expert insertion.
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