Pure gestagen pill contraceptives (minipills)

Mini-pill oral contraceptives contain only microdoses of progestogens (300–500 mcg), which is 15–30% of the progestogen dose in combined estrogen-progestogen preparations.

The mechanism of action of the mini-pill includes the following factors.

• Cervical factor: under the influence of the mini-pill, the amount of cervical mucus decreases, its viscosity increases, which reduces the penetrating ability of sperm in the periovulatory period.
• Uterine factor: the use of the mini-pill leads to changes in the endometrium that prevent implantation (premature secretory transformation, and with long-term use - endometrial atrophy).
• Tubal factor: mini-pills cause a slowdown in the migration of the egg through the fallopian tube due to a decrease in the contractile activity of the fallopian tubes.
• Central factor: In 25–30% of patients, the minipill suppresses ovulation.

The contraceptive effectiveness of the minipill is 0.3–9.6 pregnancies per 100 women/years. The minipill is a reliable method of contraception only in breastfeeding women. In other situations, it should be used only if it is not possible to use more reliable methods, such as COCs.

Main drugs of the mini-pill class

• Microlut is the lowest-dose drug in this group of contraceptives. Each pill contains 30 mcg of levonorgestrel. The package contains 35 pills (5 weeks of use).
• Exluton is one of the first drugs in this group. Each pill contains a relatively high dose of the hormone - 500 mcg of lynestrenol, due to the fact that lynestrenol requires metabolic activation in the liver, during which the dose is lost. The package contains 28 pills (4 weeks of intake).
• Charozetta is a low-dose drug. One tablet contains 75 mcg of desogestrel. In this regard, it is necessary to carefully follow the regimen, since desogestrel is metabolized during the first pass through the liver. This may lead to a decrease in the contraceptive reliability of the drug in some women. The package contains 28 tablets (4 weeks of use).

Mini-pill regimen

The drug is taken continuously at the same time of day starting from the 1st day of the menstrual cycle. Since in most cases ovulation in women is preserved, contraception can be reliable only if the mini-pill regimen is strictly followed (the deviation in the time of administration is no more than 2 hours). After childbirth, if the woman is breastfeeding, the drug is taken 6-8 weeks after the birth of the child; if she is not breastfeeding - immediately after childbirth.

Indications

• Lactation period (6 weeks after birth) - mini-pills do not affect the duration of lactation, the quantity and quality of milk.
• The presence of contraindications to the administration of estrogens (a number of extragenital diseases) or a history of estrogen-dependent complications.
• Reproductive age, including late, premenopause.
• Obesity.

Contraindications

• High risk to a woman's health in the event of an unwanted pregnancy.
• Pregnancy.
• Malignant tumors of the mammary glands.
• Concomitant administration of rifampicin, griseofulvin or anticonvulsants.
• Bleeding from the genital tract of unknown etiology.
• History of idiopathic jaundice during pregnancy.
• Liver dysfunction, severe liver cirrhosis, Dubin-Johnson and Rotor syndromes.
• Viral hepatitis in the active stage.
• Malignant and benign liver tumors.
• Severe headache, including migraine, with manifestation of focal neurological disorders.
• Thromboembolic diseases.
• Damage to the blood vessels of the brain and heart.

Side effects

• Menstrual cycle disorders.
• Nausea, vomiting.
• Depression.
• Weight gain.
• Decreased libido.
• Headache, dizziness.
• Breast engorgement.

Limitations of the method

• Less contraceptive effectiveness compared to COCs.
• The need for strict adherence to the drug intake regimen (taking it at the same time).
• Increased risk of developing functional ovarian cysts.
• Increased risk of ectopic pregnancy (its incidence is 2 per 100 women/years; however, in accordance with the WHO acceptance criteria, a history of ectopic pregnancy is classified as class 2 acceptability, i.e. the benefit of using the method exceeds the theoretical and proven risk).
• Menstrual cycle disorders:
  • the appearance of acyclic uterine bleeding;
  • shortening of the menstrual cycle to 25 days or less;
  • the appearance of uterine "breakthrough" bleeding.

Basic principles for monitoring patients taking the minipill

• If abdominal pain and/or prolonged bloody discharge from the genital tract occur, it is necessary to exclude functional ovarian cysts (rupture, torsion of the cyst stalk), ectopic pregnancy, hyperplastic processes in the endometrium, uterine fibroids, and endometriosis.
• If menstruation is delayed for 45 days or more, pregnancy should be excluded (if the patient wishes to maintain the pregnancy, it is necessary to simply stop taking the mini-pill - the low dose of progestogen in the drugs of this group does not lead to an increased risk of congenital malformations of the fetus).
• Patients with a high risk of pregnancy (the basal temperature curve remains biphasic) are recommended to use an additional method of contraception from the 10th to the 16th day of the cycle (with a regular menstrual cycle) or COCs (in the absence of contraindications).
• If intermenstrual bleeding occurs during the first months of using the mini-pill, you should continue taking the drug as usual (as a rule, the menstrual cycle returns to normal after 6–12 months) or switch to another method of contraception.

Recommendations for patients taking the mini-pill

• During the first 7 days of taking the drug, you should use an additional method of contraception.
• It is necessary to strictly adhere to the regimen of taking the drug. If you are more than 3 hours late taking the pill, you must use an additional method of contraception for 7 days.
• If you miss one tablet, take it as soon as possible and the next one at the usual time.
• If you miss 2 tablets, you should use emergency contraception.
• If your period is delayed for more than 45 days while taking the mini-pill, you should consult a doctor to determine if you are pregnant.
• During the first months of taking the mini-pill, intermenstrual spotting of blood from the genital tract is possible; if this increases, you should consult a doctor.
• In case of diarrhea, it is recommended to use additional methods of contraception.
• When planning a pregnancy, the mini-pill is stopped immediately before possible conception.

Advantages and disadvantages of progestogen-only oral contraceptives

Advantages

• Low progestogen content and no estrogenic component.
• Compared with COCs, there is a lower risk of developing cardiovascular diseases and cerebrovascular disorders.
• They do not affect carbohydrate metabolism or the blood clotting system.
• They have a therapeutic effect on dysmenorrhea, premenstrual syndrome, ovulatory pain, and inflammatory diseases of the internal genital organs.
• Rapid restoration of fertility (within 3 months after drug discontinuation).
• Can be used during lactation.
• Can be used by women smokers over 35 years of age.
• Ease of use and bioavailability.

Contraceptives

• Does not contain estrogen
• High efficiency, when taken daily at the same time IP = 0.5-5.0
• Fast effect
• No connection with sexual intercourse
• Does not affect breastfeeding
• Rapid restoration of fertility

Non-contraceptive

• May reduce menstrual-like bleeding
• May reduce menstrual pain
• May reduce the severity of anemia
• Prevention of endometrial cancer
• Reduce the risk of developing benign breast tumors
• Protect against ectopic pregnancy
• Provides some protection against pelvic inflammatory disease
• Reduce the risk of ectopic pregnancy

Flaws

• Cause changes in the nature of menstrual flow in almost all women (irregular spotting or moderate bleeding)
• Some weight gain or loss may occur.
• The method is user dependent (requires motivation and discipline)
• Irregular intake increases the risk of pregnancy
• The effectiveness of the method may be reduced when taken simultaneously with certain medications.
• Need to replenish your contraceptive supply
• Does not protect against STIs, including hepatitis and HIV infection

Rules for taking progestogen-only contraceptive tablets.

Taking gestagen-only tablet contraceptives should begin on the first day of the menstrual cycle, then taking the tablets without interruption for the time of necessary contraception. It is necessary to strictly observe the interval in taking the tablets of 24 ± 2 hours, since increasing the interval to 27 hours or more increases the risk of pregnancy and requires the use of additional contraceptive methods for 7 days after the error in taking.

When switching from COCs to mini-pills, the latter should be taken the day after taking the last COC tablet.

You should not use progestogen-only contraceptive pills!