Hormonal contraceptives involve the use of estrogen and progestin analogs to prevent pregnancy. The contraceptive effect is mediated by negative feedback at the hypothalamus, ultimately leading to reduced pituitary follicle-stimulating hormone (FSH) and luteinizing hormone (LH) secretion. Without an LH surge, ovulation does not occur. Progestin also makes implantation less likely, as it causes a thickening of cervical mucus, a decrease in tubal motility, and the inhibition of endometrial proliferation. Oral contraceptives (OCs) are the most common form of hormonal contraception, but other forms of hormone delivery, including patches, injections, and implants, also exist. In combination monophasic OCs, the dose of estrogen and progestin remains constant, while in combination multiphasic OCs it varies over the course of one cycle. The decreased total hormone doses of multiphasic OCs mitigate certain associated side effects and risks. These include bothersome symptoms such as breast tenderness, nausea, bloating, and breakthrough bleeding as well as medical emergencies such as venous thromboembolism. Because of the complications associated with hormonal contraceptives, their use is contraindicated in patients with certain medical conditions and histories, e.g., significant hypertension, ischemic heart disease, venous thromboembolism, and stroke.
Types of hormonal contraceptives 
|Overview of different types of hormonal contraceptives|
|Type||Description||Pregnancy rate in first year with typical use (with perfect use) ||Indications|
|Oral contraceptive pill||Combined oral contraceptive (COC)|| |
|Progestin-only contraceptive pills (minipill)|| |
|Contraceptive patch|| |
|Vaginal ring|| || |
|Injectable progestin|| |
|Progestin intrauterine device|| || || |
|Subdermal progestin implant|| || |
Intrauterine devices 
- Small, t-shaped birth control devices inserted into a woman's uterus to prevent pregnancy
- In the United States, they are available in two forms: nonhormonal copper-containing devices and plastic devices with progestogen hormones.
- Inserted through a quick clinical procedure
- Individuals must be tested for pregnancy and STIs before insertion.
- Copper intrauterine device: see “ ” in “ .”
Progestin intrauterine device: a progestin-releasing (e.g., levonorgestrel-releasing) contraceptive device that is placed into the uterus
- Mechanisms 
- Abnormal uterine bleeding and/or menstrual changes
- Pelvic pain following insertion
- Uterine perforation
- Active PID
- Known or suspected pregnancy
- Anatomical uterine abnormalities
- Cervical or endometrial precancerous lesions or carcinoma
- Symptomatic STIs within the last 3 months
- progestin IUD) (
See “Emergency contraception” for more information.
Mechanisms of action depend on the hormones used in the formulation.
Progestin: synthetic progesterone
- Inhibits GnRH and LH secretion and thus suppresses ovulation (main contraceptive mechanism)
- Inhibits endometrial proliferation, thereby preventing the implantation of the embryo
- Changes cervical mucus (↓ volume and ↑ viscosity) and impairs fallopian tube peristalsis, thereby inhibiting sperm ascension and egg implantation
- Inhibits follicular maturation
- Antiprogestin: inhibition of the progesterone receptor causes inhibition or delay of ovulation, suppression of endometrial maturation, and pregnancy termination
Common side effects
- Weight gain is not a side effect of hormonal contraceptives
Indications for immediate discontinuation 
- Sensory disorders (e.g., impaired vision)
- Detection of masses
- New or enhanced migraine-like headaches (especially with aura)
- New or enhanced epilepsy
- Suspected thromboembolism or thrombophlebitis
We list the most important adverse effects. The selection is not exhaustive.
- Patients desiring pregnancy in 1–2 years
- Postpartum contraception: All contraceptive options except for combination OCPs can be considered in the postpartum period.
Non-contraceptive indications 
Women who smoke and are > 35 years old should not be prescribed OCPs because of increased risk of cardiovascular side effects!
We list the most important contraindications. The selection is not exhaustive.