Natural contraceptive methods aim to help prevent pregnancy without the use of medications or devices such as condoms and diaphragms. Tese natural methods are based on observation of the woman’s body and menstrual cycle so as to estimate the fertile period.
Although these methods have the advantages of being completely natural and there is no use of hormones, they also have some disadvantages such as not being fully effective and not preventing the transmission of sexually transmitted infections.
Natural contraception requires that the woman should not have sex during their fertile period. This requires her to know their menstrual cycle which may take up to 12 cycles so as to know that period. The fertile period can be determined using some mobile methods in which data from the menstrual cycle, mucus, and temperature are used.
The main natural contraceptive methods are:
1. Calendar method or tabelinha
The method of the calendar, also known as tabelinha or Ogino Knaus method, involves avoiding sexual intercourse during the fertile period. For this reason, one should calculate the beginning and end of the fertile period based on the menstrual calender.
The calender method is determined from the last 12 menstruations. Thus, to calculate the fertile period, one must subtract 18 days from the shortest cycle and 11 days from the longer cycle. For example, for a woman whose cycle ranges between 28 days and 30 days, they should not have sex from day 10 (28 minus 18) to day 19 (30 minus 11) of each cycle. The greater the variations of menstrual cycles, the longer the abstinance period.
Women who have regular cycles obtain better results with this method. However, it is still an ineffective method of preventing pregnancy
2. Basal body temperature method
The basal body temperature method is based on variations in the temperature of the woman’s body. Temperatures may be higher during ovulation and may increase by up to 2ºC more.
This is a simple method but it requires time and discipline because the woman has to check their temperature every single day, in the morning when they get up. To measure temperature, an analog or digital thermometer can be used and the measurements must be annotated to make a graph and thus observe the most fertile days, which are the days when the temperatures are higher. Therefore, during these days, the woman should avoid sex so as to prevent getting pregnant.
This method may not be fully effective because factors such as stress, insomnia, diseases, and even the way the temperature is being ascertained can lead to increased body temperature and these bring false results.
3. Cervical mucus method
The cervical mucus method also known as the billings method is based on observation of the vaginal mucus. Soon after menstruation, the vagina usually becomes dry while during ovulation, there is production of crystalline mucus which is semi-transparent, odorless and elastic, similar to egg white. the precense of this mucus indicates that the woman is fertile and should not have sexual intercourse from the first day of the appearance of the mucus. She should wait for about 3 days once the mucus stops discarging from the vagina.
To check for the presence of mucus, the woman should insert two fingers into the vagina and analyze the color and intensity of the mucus.
The mucus method may be ineffective due to many conditions such as vaginal infections, which can affect mucus production and consistency.
4. Thermal method
The sintothermic method is a combination of tabelinha methods, basal body temperature and cervical mucus. It also takes into account common symptoms that are experienced during the fertile period such as pain and tenderness of the breasts or abdominal cramps.
It can be a bit reliable when three natural contraceptive methods are combined, yet this is still not fully effective and it does not prevent the transmission of sexually transmitted infections.
5. Interrupted intercourse method
The interrupted intercourse method implies the man removing the penis from the vagina at the time of ejaculation, so as to limit the chances of the sperm reaching the egg. However, during foreplay and even before ejaculating, the penis usually releases mucus that contains sperm.
Therefore, even without ejaculating into the vagina, pregnancy can still occur. In addition, it is necessary that the man has enough self-control to know exactly when he is about to ejaculate. It also takes a lot of confidence of the woman in the partner when It comes to using the interrupted intercourse method.
The effectiveness of this method is low as it interrupts the intimate moment of the couple.
6. Ovulation test
The ovulation test is performed with kits that measure the amount of luteinizing hormone in the urine. This is the hormone responsible for the maturation of the egg and it usually increases from 20 to 48 hours before ovulation. Thus this test indicates when the woman is commencing her fertile period. She should therefore avoid sexual intercourse so as to reduce the chances of becoming pregnant.
The ovulation test can be purchased in pharmacies and it is easy to use.
7. Lactational amenorrhea method
The lactational amenorrhea method is based on the idea that the woman cannot become pregnant during the period when she is breastfeeding. This period is also marked by the absence of menstruation, called amenorrhea.
During this phase, the woman is not fertile, and she usually returns to ovulate 10 to 12 weeks after delivery.
The method of lactational amenorrhea is not a good contraceptive method, because the woman may ovulate without noticing, mainly because there is no prediction of when menstruation will return to normalcy. In addition, it is not recommended for women who do not breastfeed.