Methods of contraception
Contraceptives stop ovulation, block sperm and ovum from meeting, or prevent implantation: natural methods, barriers, IUDs, hormonal pills, injections, implants and sterilisation.
Natural and barrier methods
| Method | How it works | Notes |
|---|---|---|
| Periodic abstinence | No coitus from day 10 to 17, when ovulation is expected | No devices or medicines; high chance of failure |
| Withdrawal (coitus interruptus) | The male withdraws the penis just before ejaculation, so there is no insemination | High chance of failure |
| Lactational amenorrhea | Ovulation and the cycle do not occur during intense breastfeeding after delivery | Effective only up to about 6 months after delivery |
| Condoms (male, e.g. 'Nirodh', and female) | A thin rubber or latex sheath covers the penis, or the vagina and cervix, so semen does not enter the female tract | Disposable and private; also protect against STIs and AIDS |
| Diaphragm, cervical cap, vault | Rubber barriers placed over the cervix during coitus, blocking the entry of sperms | Reusable; used with spermicidal creams, jellies or foams |
Intra-uterine devices (IUDs)
| Type | Examples | How it works |
|---|---|---|
| Non-medicated | Lippes loop | Increases phagocytosis of sperms inside the uterus (all IUDs do this) |
| Copper-releasing | CuT, Cu7, Multiload 375 | Cu ions also suppress sperm motility and fertilising capacity |
| Hormone-releasing | Progestasert, LNG-20 | Also make the uterus unsuitable for implantation and the cervix hostile to sperms |
Oral pills, injections and implants
- Oral pills contain small doses of progestogens alone, or progestogen-estrogen combinations.
- A pill is taken daily for 21 days, starting within the first five days of the cycle. After a 7-day gap, when menstruation occurs, the same pattern is repeated.
- Pills inhibit ovulation and implantation, and change the cervical mucus to stop or slow sperms.
- Saheli is a once-a-week pill with a non-steroidal preparation. It has very few side effects and high contraceptive value.
- Injections and implants under the skin use the same hormones and work the same way, but they last much longer.
- Emergency contraception: progestogens, progestogen-estrogen combinations or IUDs, given within 72 hours of rape or casual unprotected intercourse.
Sterilisation: vasectomy vs tubectomy
Both block the transport of gametes. They are highly effective, but their reversibility is very poor, so they are terminal methods for couples who want no more children.
Points to remember
- IUDs are inserted by doctors or expert nurses through the vagina into the uterus. They suit women who want to delay pregnancy or space children, and are among the most widely accepted methods in India.
- Choose any method only after consulting a qualified medical professional.
- Contraceptives are not a regular need for reproductive health. They work against natural reproductive events.
- Possible side effects include nausea, abdominal pain, breakthrough bleeding, irregular menstrual bleeding, and even breast cancer. Your textbook says these are not very significant, but should not be totally ignored.
- Only condoms also protect against STIs, including HIV.
Government health centres in India provide condoms, oral pills and the Copper-T. The IUD is one of the most widely used methods for spacing children. A doctor's advice helps a couple choose the method that suits them.
3 marks: “How do copper-releasing IUDs, hormone-releasing IUDs and oral pills prevent pregnancy?” All IUDs increase phagocytosis of sperms; Cu ions suppress sperm motility and fertilising capacity. Hormone-releasing IUDs also make the uterus unsuitable for implantation and the cervix hostile to sperms. Pills inhibit ovulation and implantation and alter cervical mucus.
5 marks: “Describe five methods of contraception, giving an example of each and how it prevents conception.” Natural (periodic abstinence, day 10 to 17); barrier (condoms, diaphragms with spermicides); IUDs (CuT: Cu ions; LNG-20: hormones); oral pills, injections and implants (progestogens or progestogen-estrogen; inhibit ovulation and implantation; Saheli is a non-steroidal weekly pill); surgical (vasectomy, tubectomy; block gamete transport).
2 marks: “What is lactational amenorrhea? Why is it reliable only for a short time?” Absence of menstruation and ovulation during intense breastfeeding after delivery. It works only while the mother breastfeeds fully, up to about six months; after that, ovulation may return.
IUD trio L-C-H: Lippes loop (non-medicated), Copper (CuT, Cu7, Multiload 375), Hormone (Progestasert, LNG-20).