Know the hormones used in birth control pills

Today, most women use some contraceptive method to prevent an unplanned pregnancy. Contraceptive ring, subcutaneous implant, transdermal patch and IUD are some of the methods available, but certainly the use of pills is still the best known.

Nevertheless, few people know that there are different types of pills and that, since the first pill was launched, to the present day, much has been modernized in the world of contraception. Below, César Eduardo Fernandes, scientific director of Sogesp (Society of Gynecology and Obstetrics of São Paulo) explains all the details on the subject.

Different types of pills

César Eduardo Fernandes points out that today there are so-called combined oral contraceptives (or combined pills), which associate estrogen with progestogen (progesterone-derived synthetic hormone), and oral progestogen-only pills.

According to Fernandes, both types are effective in inhibiting ovulation and therefore in preventing pregnancy. "The fundamental difference between them is that estrogen has the role of controlling the menstrual cycle, ie in combined oral pills there is a good predictability of menstruation, which progestogen-only pills do not offer," he says.

Progestogen-only pills are indicated for women who have contraindications to estrogen use, such as women with a history of thromboembolism and cardiovascular problems, smokers over 35 and breastfeeding women.

Understand below the differences between the two pill types:

Combined Pill

Frequency of use: daily.

Use: method that combines two hormones (estrogen and progestogen). Daily oral intake at the same time. There are several different types in quantity of pills, dosages and types of hormones.

Benefits: good cycle control thanks to estrogen. Therefore, in pills with a 21-long and 7-pause scheme, and in 24-pill and 4-pause pills, the woman has predictable bleeding on the pause of the pack (hormone-free period), with less leakage during the pack. In modern pills, this bleeding is commonly shorter and scarcer.

Disadvantages: The combined pills are not indicated for women who have contraindications to estrogen use, such as women with a history of thromboembolism and cardiovascular problems, smokers over 35 and breastfeeding women.

Progestogen pill

Frequency of use: daily.

Use: progestogen-only daily tablet, which should be taken every day at the same time. With this type of pill, there is no gap between the packs.

Benefits: This type of pill is indicated for women who have contraindications to the use of estrogen, such as women with a history of thromboembolism and cardiovascular problems, smokers over 35 and those who are breastfeeding.

Disadvantages: This type of pill does not have good cycle control and there may be leaks during the pack.

Hormones used in progestogen-only pills

The most commonly used progestogens in pills with this component alone, according to Fernandes, are Desogestrel 75, Desogestrel and Norethisterone.

Below you know some characteristics of these progestogens:

Desogestrel: It has mild androgenic effect (increased male characteristics such as hair, skin oils and increased libido).

Norethisterone: has androgenic effect.

Hormones used in the combined pills

According to Fernandes, the progestogens commonly used in the combined pill are:

Levonogestrel: has moderate androgenic effect.

Desogestrel: has mild androgenic effect.

Gestodene: has mild androgenic effect. It also has diuretic action.

Norgestimate: has mild androgenic effect.

Drospirenone: has antimineralocorticoid effect (prevents water retention).

Nomegestrol Acetate: has very similar effect to that of natural progesterone.

"Recently, progestogen nomegestrol acetate has been incorporated into the so-called natural pills, as this progestogen resembles that naturally produced by the woman's body," says Fernandes.

They stand out as the estrogens used in the combined pill:

Ethinylestradiol: Semi-synthetic estrogen (has strong estrogen effect, which can cause some side effects like weight gain and nausea).

17-B Estradiol: natural estrogen with less estrogenic effect compared to ethinyl estradiol.

Fernandes explains that the estrogen used since the invention of the pill has been Ethinyl Estradiol. "It is a semi-synthetic hormone, that is, derived from the natural hormone estradiol, but that does not exist free in nature or in the woman's body," he says.

"Recently, estrogen 17-B Estradiol has been incorporated into so-called natural pills, as it resembles that naturally produced by a woman's body," he adds.

How to choose a good pill?

Knowing that there are different types of pills it is common that the question arises: what to consider when choosing?

Some points can be observed, for example: Levonorgestrel, which was one of the first progestogens used in the composition of the pills, has androgenic action, that is, similar to male hormones. Thus, it can cause higher skin oils, acne and increased hair. However, it may be a good option for women who complain of falling libido with pills.

Another example is drospirenone, which avoids water retention and can be very helpful for those women who complain of premenstrual swelling.

But, it is noteworthy, these are just a few examples, as the choice of contraceptive should always be made in conjunction with the doctor.

• The professional can evaluate the factors that interfere with the contraceptive adoption, giving the patient information on efficacy, mode of action, frequency and ease of use, side effects and route of administration. After this guidance, women can exercise their right to choose the contraceptive method according to their lifestyle. Regardless of the choice, she should feel safe and confident with the method and strictly follow the recommendations to use the package leaflet to ensure the expected effectiveness ?, concludes Eduardo Fernandes, scientific director of Sogesp.

How Birth Control Pills Work, Animation (May 2024)