Depending on the composition of the hormones, such agents prevent ovulation (“ovulation inhibitors”), thicken the mucus in the cervix and thus make it more difficult for sperm to penetrate, or prevent the implantation of the egg in the uterus. In recent years, a number of alternatives have been developed in addition to the classic “birth control pill” used since the early 1960s.
Oral contraceptives (birth control pills).
They are swallowed daily in tablet form for 21 or 22 days, followed by a break from taking them for 7 or 6 days. They protect immediately, but must be taken regularly, no later than 12 hours after the normal schedule. Antibiotics and some antiepileptic drugs may interfere with their effect.
Several categories are distinguished in this still most popular form of contraception:
- Conventional pill (combination preparation): prevents ovulation by a mixture of estrogens and progestins. In single-phase preparations, the mixing ratio remains constant over the period of intake, in two-phase and three-phase preparations it changes to better match the female cycle (Pearl index: 0.1-0.9).
- Micropill: is similar to a conventional pill, but has a lower estrogen content (Pearl index: 0.2-0.5)
- Minipill: it contains only low-dose progestogens and therefore must be taken on a strict schedule (Pearl index: 0.15-3).
The new progestin drospirenone (“Yasmin”), used since 2002, counteracts water retention caused by estrogens and the associated weight gain, has positive effects on the skin and sometimes helps with premenstrual syndrome. Other progestins that have been known for some time, such as chlormadinone and dienogest, also work against acne, hair loss, and increased body hair.
Vaginal ring (NuvaRing).
This soft, pliable ring is made of plastic, is 54 mm in diameter, and contains a mixture of estrogen and progestin in a depot. It releases these hormones constantly and acts like a mini-pill (Pearl index: 0.65). It is inserted by the women themselves like a tampon and removed after three weeks. After a week’s break, the next one is inserted. It has been available on the German market since February 2003.
Contraceptive patch (Evra or Lisvy).
The 4.5 x 4.5 cm, skin-colored Evra hormone patch has been available in Germany since 2003. It releases its estrogen-progestin mixture continuously through the skin into the body, is stuck to the buttocks, upper arm, abdomen, or upper back, and is changed weekly. As with the conventional pill, a week’s break follows after three weeks (Pearl index: 0.88; worse in overweight women).
Since 2015, the lower-dose, transparent, and approximately 11 cm² contraceptive patch Lisvy has also been available (Pearl index: 0.81; insufficient data available for severely overweight women).
Contraceptive sticks (Implanon).
This contraceptive method using a rod that delivers hormones has been on the market in Germany since June 2000. Like the three-month injection, it contains only progestins that are released slowly; its contraceptive protection is very safe and lasts for more than three years (Pearl index: 0.1-0.9). The 3-4 centimeter long and 2 millimeter thin rod is inserted under the skin by a gynecologist, on the inside of an upper arm.
Three-month injection
Similar to the mini-pill, this contraceptive contains only progestins, but in depot form. It is injected every three months by the gynecologist into the upper arm or buttock muscle, from where it slowly releases its active ingredients (Pearl index: 0.2-0.5).
Hormonal IUD (Mirena).
Like the copper IUD, the hormonal IUD (“intrauterine system” = IUS) is inserted into the uterus by the gynecologist and can remain there for up to 5 years. Instead of copper, it continuously releases progestins from there. It combines the advantages of the classic IUS with the methods of the mini-pill or three-month injection, making it very safe (Pearl index: 0.05-0.1).
