Introduction
Birth control, also known as contraception and fertility control, is a method or device used to prevent pregnancy. Birth control has been used since ancient times, but effective and safe methods of birth control only became available in the 20th century.
Why are contraceptives used?
Contraception allows them to put off having children until their bodies are fully able to support a pregnancy. It can also prevent pregnancy for older women who face pregnancy-related risks. Contraceptive use reduces the need for abortion by preventing unwanted pregnancies.
HORMONAL CONTRACEPTIVES
These are hormonal preparations used for reversible suppression of fertility. Because of our alarming population trends, antifertility drugs are the need of the day.
In the earlier part of 20th century, methods of contraception used (condoms, diaphragms, sper spermicidal creams, foam tablets, etc.) were intimately related to sexual intercourse, therefore, despised by most couples. These also have higher failure rate.
There is successful use of an oral progestin for contraception separating fertility control from coitus.
It was soon discovered that addition of a small quantity of an estrogen enhanced their efficacy; combined pills have become the most popular method of contraception, particularly because the hormone content of the pills has been reduced, minimizing the potential harm and affording other health benefits.
FEMALE CONTRACEPTION
With these drugs, fertility can be suppressed at will, for as long as desired, with almost 100% confidence and complete return of fertility on discontinuation.
The efficacy, convenience, low cost and overall safety of oral contraceptives (OCs) has allowed women to decide whether and when they want to become pregnant and to plan their activities.
A variety of oral and parenteral preparations are now available offering individual choices.
Best contraceptive
Contraceptives that are more than 99% effective: contraceptive implant (lasts up to 3 years)
- intrauterine system, or IUS (up to 5 years)
- intrauterine device, or IUD, also called the coil (up to 5 to 10 years)
- female sterilisation (permanent)
- male sterilisation or vasectomy (permanent)
What is the safest contraceptive?
Condoms are your safer sex superhero: they’re the only way to get protection from pregnancy and STDs during vaginal sex. No birth control method is perfect. So using condoms with another type of birth control (like the implant, IUD, or pill) gives you backup protection in case either method fails.
Which contraceptive pill is the best?
A low dose pill such as Loestrin 20 might be the best contraceptive pill for you. These types of contraceptive pill contain both oestrogen and progesterone, but with a lower dose of oestrogen compared to the regular combined pill. This means that oestrogen related side effects are often reduced.
Some contraceptive drugs
Norgestrel sold under the brand name OVRAL among others, is a progestin medication which is used in birth control pills and in menopausal hormone therapy. It is available both in combination with an estrogen and alone. It is taken by mouth.
Levonorgestrel is a synthetic progestogen similar to Progesterone used in contraception and hormone therapy. It is used as a single agent in emergency contraception, and as a hormonal contraceptive released from an intrauterine device, commonly referred to as an IUD.
Desogestrel, sold under the brand names CERAZETTE and MIRCETTE among many others, is a progestin medication which is used in birth control pills for women. It is also used in the treatment of menopausal symptoms in women. The medication is available and used alone or in combination with an estrogen.
Norethisterone, also known as norethindrone and sold under many brand names, is a progestin medication used in birth control pills, menopausal hormone therapy, and for the treatment of gynecological disorders.
MALE CONTRACEPTIVE
The only way to suppress male fertility by drugs is to inhibit spermatogenesis. Though considerable effort has been made in this direction and effective drugs have been found, no satisfactory or acceptable solution is yet tangible. Reasons are
- Complete suppression of spermatogenesis is relatively difficult without affecting other tissues: millions of spermatozoa are released at each ejaculation ,a single ovum per month in women.
- Spermatogenesis takes 64 days. A drug which even completely inhibited spermatogenesis will take a long latent period to produce infertility. Accordingly, return of fertility will be slow.
- Gonadotropin suppression inhibits testis terone secretion as well, resulting in loss of libido and impotence: unacceptable to all men and to most spouses.
- Risk of adverse effects.
- Most importantly—men don’t get pregnant: few would be ready to bear the contingency of regular medication so that their sexual partners do not become pregnant.
Drugs and approaches tried are:-
- Antiandrogens Depress spermatogenesis, but raise Gns; cause unacceptable loss of libido.
- Estrogens and progestins Act by suppressing Gns cause unacceptable feminization.
- Androgens -They inhibit Gns but have poor efficacy. Even combination with progestin is not reliable.
- Superactive GnRH analogues They inhibit Gn release by continuous action; inhibit testosterone secretion as well; produce impotence, loss of libido.
- Cytotoxic drugs Cadmium, nitrofurans and indoles suppress spermatogenesis, but are toxic.
- Gossypol It is a nonsteroidal compound, obtained from cotton seed; It is effective orally causes suppression of spermatogenesis and reduces sperm motility-infertility develops after a couple of months.
- Fertility is restored several months after discontinuation. However, about 10% men remain oligozoospermic. During treatment serum LH and testosterone levels do not change: libido and potency are not affected. The mechanism of action is uncertain; probably involves direct toxicity on seminiferous epithelium.
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