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11.2.1. Contraceptive methods

Contraceptive methods

The sex in humans are not always performed for reproductive purposes. Having a child has to be a premeditated act and we have to be responsible with our sexuality. Therefore, if we want to have sex and not have children, we must use a contraceptive method.

The contraceptive serve for a responsible family planning and preventing pregnancies unwanted birth control and global overpopulation, and some as a means to prevent the transmission of some sexually transmitted diseases (STDs).

Contraceptive methods are classified into several groups:

Natural methods

Natural contraceptive methods are based on the physiological changes that are detected throughout the menstrual cycle, such as temperature, mucus, etc. According to this, sexual intercourse can only be performed without risk of pregnancy on days when the woman is not fertile. They also do not protect against sexually transmitted diseases.

Although we include them here, because of their low efficacy, they should not be used as contraceptive methods. They are unsafe because menstrual cycles are sometimes not regular and can be altered by many factors (hormonal, illnesses, stress, etc.).

Natural procedures

  • Ogino or the rhythm or the calendar. It is based on not having sex when the woman is ovulatingTo do this, count the days of the menstrual cycle and choose the days when the woman is least fertile.
  • Body or basal temperature. The body temperature of the woman is measured during all the days of the menstrual cycle, in the same place and at the same time, which is usually between 36 and 36.5º. During ovulation, this temperature rises to about 37º. It's about avoiding sex on the day your temperature rises.
  • Cervical mucus. The fluid in the cervix, the neck of the uterus, becomes clear when the woman is ovulating, so sexual intercourse should be avoided.

El método de Ogino se basa en evitar tener relaciones sexuales los días en que la mujer es fértil, hacia la mitad del ciclo aproximadamente

By Bea.miau (Own work) [CC0], via Wikimedia Commons

Unsafe performances

They cannot be considered or contraceptive methods due to their high risk of failure. Some of these unsafe performances are:

  • Vaginal washing after sexual intercourse. Some sperm can reach the cervix before washing.
  • Coitus interruptus or "going backwards". It consists of the man ejaculating outside the vagina, but before ejaculation, the precum may contain some sperm and pregnancy may occur. It is the method with the highest failure rate.

Barrier methods

These methods act as a barrier that prevents the sperm from moving to the egg.

Preservative o male condom

The condom is a thin, elastic latex or polyurethane sheath that is placed on the erect penis and collects the semen from ejaculation, preventing sperm from entering the uterus.

If used correctly, the condom has a high efficacy. In addition, it is useful to prevent sexually transmitted diseases.

Cómo se pone el preservativo o condón

By BruceBlaus (Own work) [CC BY-SA 4.0], via Wikimedia Commons

Video: How to use a condom.

Female condom

It is a sheath that is placed inside the vagina, acting in a similar way to the male condom, preventing sperm from reaching the uterus. It does not have to be used in conjunction with the male condom. They also prevent STDs.

Preservativo o condón femenino

By Ceridwen (Own work) [CC BY-SA 2.0 fr], via Wikimedia Commons

Vaginal diaphragm

It is a latex cap that is placed at the bottom of the vagina, covering the cervix so that sperm cannot access it.

The doctor needs to take measurements for the diaphragm. It does not protect against STDs.

Diafragma vaginal

By Dake (Own work) [CC BY-SA 2.5., via Wikipedia

Mechanical methods

They are devices that prevent the zygote from nesting in the uterus.

IUD (intrauterine device)

It is a metal or plastic device that has a T-shape that is inserted into the uterus, preventing the ascent of the sperm and the implantation of the fertilized ovum. It has to be placed by a gynecologist and undergo periodic check-ups.

Its effectiveness is high, more recommended for women who have already had children. It does not protect against sexually transmitted diseases.

DIU: Dispositivo intrauterino

By BruceBlaus. When using this image in external sources it can be cited staff (2014). "Medical gallery of Blausen Medical 2014". WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436. (Own work) [CC BY 3.0], via Wikimedia Commons

Chemical methods

They use chemical substances that intervene on the eggs or sperm. Some of these methods are:


They are creams or gels that are placed in the vagina before intercourse and remove sperm or alter its mobility. Their efficacy is low, but they are often used in addition to other barrier methods, such as the condom or the diaphragm.

Using spermicides does not protect or prevent STDs .

Birth control pills, vaginal patches, injections, or rings

They contain sex hormones that alter the ovarian cycle, preventing ovulation. They must be prescribed by a doctor. Its efficiency is very high. It does not protect against sexually transmitted diseases.

The postcoital or "morning after" pill is not a preventive method but an emergency method, which should only be used when others have failed or there has been a violation, as it may pose a risk to the woman's health. It is not an abortion pill, since its function is to prevent the implantation of the ovum.

It also does not protect or prevent sexually transmitted diseases.

Anticoncepción Oral de Emergencia. - YouTube. (s. f.). Recuperado 16 de julio de 2013, a partir de

Surgical methods

They are surgical interventions in the ducts of the reproductive system. It is the best contraceptive method if it is very clear that you do not want to have more children, since it is a definitive method. It is not recommended for young people and it does not prevent STDs.

Tubal ligatures

Operation that consists of sectioning and sewing the fallopian tubes to prevent the passage of eggs and sperm, preventing fertilization.

Very effective, without affecting the sexual relationship. Hormonal balance is maintained, menstruation does not vary.

It should be considered a definitive method of contraception, although the functionality of the fallopian tubes can now be restored.


Surgical intervention consisting of sectioning and sewing the vas deferens to prevent the sperm from escaping to the outside. The ejaculation remains normal, except that the semen lacks sperm.

Its effectiveness is very high, without affecting the hormonal balance or sexual relations. It should be considered as a definitive contraceptive method, although currently the previous situation can be recovered.


By Rhcastilhos (Own work) [Public domain], via Wikimedia Commons

Activity: Contraceptive methods.

Activity: Characteristics of contraceptive methods.

Answer in your notebook

11.10.- What contraceptive method is the most effective to avoid sexually transmitted diseases? Reason for the answer.


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