Perl index - the effectiveness of the selected method of contraception

The development of medicine in many ways has not been in vain. In addition to new methods of treatment, medicines and medical specialties, scientific progress has given people many methods of contraception, previously unknown. Their effectiveness is estimated using an indicator known as the Perl index.

Modern Contraception

Sexual literacy in the 21st century is an important component of a mature personality. Understanding how to protect yourself and your partner from diseases or unwanted pregnancies is the first step towards a healthy intimate life. The variety of contraceptives opens up a huge number of options and opportunities. But there is a difference between them: firstly, their action is based on different principles, and secondly, not every method will approach any situation.

For example, condoms are more suitable for one-time and intermittent use, they are sufficiently effective to protect against various diseases and infections, although not all. Caps working on the same principle will no longer become a barrier to pathogenic bacteria and viruses, and therefore more suitable for couples who are confident in each other.

Hormonal contraceptives are easy to use and can help women cope with some gynecological diseases. However, they have zero effectiveness in protecting the body from infection. Thus, they are usually used by couples who have long been in a relationship.

Another category is spermicides. Their action is based on the neutralization of spermatozoa with the help of various kinds of substances. This method also does not protect against diseases, if it is not combined with barrier contraception.

So, what to choose? It is worth, among other things, pay attention to how well these or other methods cope with their task.

Performance indicator - Pearl index

Choosing a suitable method of contraception for yourself, it is worth considering not only how convenient it will be to use, but also take into account the degree of its reliability. To assess it, there is the Perl index. Another one is its failure rate. As the name implies, the lower it is, the better.

For the first time this method of calculating the effectiveness of contraceptives, used so far, was proposed in 1933 by the American biologist R. Perl. On the basis of this indicator, as well as personal preferences and some other factors, it is worth choosing the way to protect each particular pair.

How is it calculated?

The evaluation method is very simple: 100 women use the same method of protection during each contact during each year. At the end of this period, the number of pregnancies is fixed. The smaller the Pearl index, the more effectively the contraceptive method is considered.

Nevertheless, it is worthwhile to distinguish between theoretical and practical reliability. Incorrect or negligent use may cause the method simply not to work. So, the reliability of condoms, for example, depends on whether they were worn in time, whether there was contact of the genitals before, whether the size is suitable, etc. That is why often the failure rate is indicated not as an exact number, but as a period of values.

So, how does this all look in practice? Below are the main methods of contraception, and opposite each item - the Perl index. The table is chosen for greater clarity.

Above, only large groups of family planning methods were listed. A little more about some of them, including their effectiveness, we'll talk further.

Hormonal contraceptives

Special injections, plasters, pills, rings, intrauterine spirals - forms a huge variety. Some of them require daily attention, others need to be remembered once a month or even a quarter. For example, the hormonal ring - a contraceptive that has become popular relatively recently - is placed in the vagina and remains in it for 3 weeks.

The essence of this category of contraceptives is the regulation of the work of the reproductive system of a woman - she seems to "fall asleep". As a result, ovulation does not occur, cervical mucus thickens , often even a decrease in libido. And although the latter is not a very welcome consequence, all these factors lead to a significant reduction in the likelihood of pregnancy.

Hormonal contraception is good for everyone, the only negative - it has a lot of contraindications and side effects. Smoking women, for example, risk the health of the hematopoietic system and blood vessels. There are other serious problems, so that the appointment of any type of funds from the hormonal group should be done only by a doctor after the examination. Examination, ultrasound, a smear, several blood tests - that's what you might need to understand what contraceptives suit. The Pearl index in theory for this category is quite low - less than 1. An exception is some methods of postcoital or emergency contraception, they can be neglected. However, in practice, it is still higher, because many women are not too careful at admission, miss or late with tablets, forget about reducing their effectiveness with the simultaneous use of certain antibiotics, etc. And yet it still remains one of the most reliable Ways.

Condoms

Barrier contraceptives are less diverse than the previous group. And the most popular means in this category are condoms. By the way, there are their female counterparts, as well as special caps that are put on the cervix, but they are much less common.

The undeniable advantage of condoms is that, with sufficient effectiveness, they also protect against some STDs. This does not mean that you can not be afraid of any infection, but the probability of catching it significantly decreases. Reliability of condoms, according to different data, is from 2 to 12. In fact, this is just the case, when everything depends on the correct application. The product needs to be put on time and correctly, and then the probability of pregnancy will be minimal. In addition, modern manufacturers often immediately put it in a spermicide lubricant, thus further reducing the chances of an unexpected outcome.

Spermicide

To this group are two absolutely different methods. The first - gels, candles, lubricants and other means aimed at chemical neutralization of spermatozoa. The second is an intrauterine device containing copper. The first for all its simplicity has several disadvantages. Firstly, it requires patience - in order for the funds to start acting, you need to wait 10-15 minutes, and secondly, it has a relatively low efficiency - 3-21. The second requires a compulsory visit and consultation of a doctor. But the reliability of the spiral is quite high - 0.9-3.

Surgical

This group includes extremely effective methods, where by means of operations a man or a woman with practically 100% guarantee is deprived of the opportunity to acquire offspring. Such interventions have a number of social restrictions in many countries and are considered quite serious. Fortunately, in most cases they are reversible.

Natural

A set of methods related to this category include those that are based primarily on how well a woman knows and feels her body. The fact is that the probability of pregnancy changes during the menstrual cycle. It is quite large during ovulation, lasting about 72 hours, a week before and as much after. The rest of the time it's almost impossible to get pregnant.

Virtually all methods of natural contraception are based on the fact that the woman in different ways fixes the time of ovulation and refrains from contacts at this time. With skillful application and a combination of several methods, this can be quite effective, but not everyone wants to clog their heads with daily schedules, when one can simply take advantage of medical advances. For example, the already mentioned ring-contraceptive can be picked up only once in 3 weeks, and in the case of injections, remember only 4 times a year. However, some people prefer to use their natural, natural resources, and this choice should also be respected.