The female condom

The female condom is one of the hormone-free contraceptives and, like the male condom, prevents sperm from entering the uterus. It is a tubular structure with the open end protruding from the vagina and the closed end covering the cervix. The calendar method was introduced by Hermann Knaus and Kyusaku Ogino in the 1930s as a natural contraceptive method.

According to the WHO (World Health Organization), however, this method should no longer be counted among the natural contraceptive methods today, as it is very unsafe. The calendar method is based on the fact that the natural menstrual cycle is used to determine when the “fertile days” will occur. During these fertile days you should refrain from sexual intercourse and thus prevent pregnancy.

The idea is based on the fact that fertilization of the egg (oocyte) can only occur within a certain period of time, around ovulation. With a cycle of 28 days, ovulation occurs approximately on the 14th day (more precisely between the 12th and 14th day) after the start of the last menstrual period. The egg cell is only capable of being fertilised 5 – 12 hours after ovulation.

In contrast, sperm have a survival time of about three days. The idea behind the calendar method is that it is not possible to become pregnant with a safe distance of three days to both directions of ovulation. In practice, women who want to use this method have a menstrual cycle that is as regular as possible and must record it for over a year.

The records are then used to determine how long the shortest and longest menstrual cycles were. Once these data are available, the beginning and end of the fertile days can be calculated. According to Knaus’ method, 17 days are subtracted from the shortest cycle.

The result corresponds to the first fertile day. From the longest cycle 13 days are subtracted. The result corresponds to the last fertile day.

Hormone-free contraception

This means that the first fertile day would be the 8th day after the start of the last menstruation and the 15th day after the start of the last menstruation would be the last fertile day. During this period one should therefore be abstinent. Ogino’s method is based on the same principle, but 18 days are subtracted from the shortest cycle and 11 from the longest cycle.

The calendar method is rated overall with a Pearl Index of 15 – 38 (! ), depending on the study, as rather uncertain. It also requires strict discipline and respect from the partner.

This method is generally only applicable to women with a regular cycle. However, even in women with a regular cycle, it can be drastically lengthened or shortened due to illness, psychological stress or various environmental influences, so that the calculated fertile days do not correspond to the actual fertile days and thus adequate protection is no longer guaranteed. The principle of temperature measurement for contraception is based on the fact that after ovulation there is an increase in body temperature of about 0.5o Celsius.

This occurs approximately on the 14th day after the last menstrual bleeding. On this day, the corpus luteum also starts to function. The corpus luteum produces the sex hormone progesterone, whose increase leads to the temperature rise.

The determination of the temperature can thus be used to determine the time of ovulation. Since pregnancy cannot normally occur approximately three days after ovulation, it can be assumed that after a three-day temperature increase of 0.5o Celsius, fertilization of an egg cell no longer occurs. In practice, the woman has to determine the basal body temperature.

This is the temperature just after waking up and before getting up. The temperature should therefore still be measured in bed in the anus (rectally) or under the armpit (axillary). It should always be taken at the same place body to have as accurate a comparison as possible of the basal body temperatures of different days.

It should also be done under the same conditions.This means that ideally the temperature should be taken at about the same hour, after about the same number of hours of sleep, etc. Overall, the temperature method with a Pearl index of about 3 is a method that is not necessarily safe. A disadvantage is certainly that you have to keep a temperature calendar consistently.

Missing a measurement makes the method useless. The measured temperatures can also be inaccurate for a variety of reasons. An illness associated with fever, too few hours of sleep or psychological stress can quickly lead to falsified temperature measurements. Also, some women do not have such a clear basal body temperature, which rises in the second half of the cycle, and therefore cannot use this method.