Hormonal contraception refers to birth control methods that act on the hormonal system.

Currently, all hormonal contraceptives are designed for use by women rather than men, though research on a male hormonal contraceptive (“the male Pill”) has been underway for some time. Because women are typically fertile for only a few days during each menstrual cycle, usually releasing only one egg during the cycle, it is easier to disrupt their fertility with hormones than it is to disrupt mens’, since men are perpetually fertile and typically release millions of sperm during sexual intercourse.

Hormonal contraceptives may be introduced into the woman’s body in many different ways, among them orally, vaginally, transdermally, or through injections or implants. The oral method was the first and most famous of these; within a few years of its introduction in 1960, “the Pill” became one of the most popular contraceptives in the United States and elsewhere, and it remains so today.

Hormonal contraception may act in one or more ways to prevent pregnancy. It may cause ovulation to cease, preventing the possibility of fertilization; it may thicken the woman’s cervical mucus, making penetration of the uterus by sperm more difficult; or it may alter and thin the endometrium so that a fertilized egg has difficulty implanting. (Technically, if the drug works in this third fashion, it acts as a contragestive rather than a contraceptive, since it has not prevented conception, acting instead to prevent gestation.)

Like all methods of birth control, hormonal methods have certain advantages and disadvantages.

• Advantages:

• • If used properly, hormonal contraceptives are highly effective; except for abstinence, vasectomy, and tubal ligation, no other method of birth control has as great a degree of effectiveness. This also often allows the couple to relax and enjoy intercourse more fully.

• • Unlike nearly all other birth control methods, hormonal contraceptives are effective during the woman’s entire cycle, and they completely separate the act of contraception from sexual intercourse. The couple takes no birth control action either before, during, or after sex. Intercourse may thus be very spontaneous and natural-seeming, which can be highly pleasurable to both partners, and it may continue without any interruption until the man reaches orgasm and ejaculates within the woman’s vagina.

• • Hormonal contraceptives may also have health or other benefits, among them reduction of the incidence of some types of cancer; menstrual periods that are more regular and predictable; periods that are shorter, lighter, or both; increased breast size; and reduced acne in younger women.

• Disadvantages:

• • Hormonal contraceptives offer no protection against sexually-transmitted infections, placing non-monogamous individuals and couples at high risk for contracting such an infection.

• • Like many other forms of birth control, hormonal contraceptives rely on the woman to use them correctly. Some, such as implants, require relatively little attention; others, such as injections or transdermal patches, require a schedule ranging from a week to several months. Still others—the wide varieties of the Pill—require a daily schedule. Even a slight deviation from the proper schedule can destroy the method’s effectiveness.

• • Hormonal contraceptives may often have slight, moderate, or serious side effects or health risks, such as weight gain, loss of libido, hair loss, mood swings, or blood clot/stroke (this last is of special concern to women who smoke).

• • Like many other forms of artificial contraception, hormonal contraception is objectionable to some religious traditions. In cases where the method may in fact function as a contragestive (killing an already-fertilized egg), these objections may be even stronger

• • Hormonal contraceptives require a prescription in the United States and most other countries because of potential health risks.

Because so many variables are involved, hormonal contraceptives may work better for some women and couples than for others, and some types of hormonal methods may work better than other types. Despite their drawbacks, hormonal contraceptives tend to be very popular. Typically a couple may start out by using a more readily available method, often condoms, spermicide, withdrawal or some combination of methods. Later, once the relationship becomes steady or long-term and intercourse grows more frequent, the couple turns to hormonal contraception. It is possible, and not unusual, for a woman to use hormonal contraceptives for most of her childbearing years (from teens to forties), ceasing to contracept only when having a child and then contracepting again until the next child or until menopause.

• Chemical methods
  • Combined estrogen & progesterone:
    • Combined oral contraceptive pill ("The Pill")
    • Contraceptive patch
    • Contraceptive vaginal ring
    • Lunelle (monthly injection)
  • Progesterone used alone:
    • Progesterone only pill (POP)
    • Depo Provera (injection every three months)
    • Implants (such as Norplant or Implanon)

(Most combined pills and POPs may also be taken in high doses as emergency contraception, also known as the morning after pill.)

• Intrauterine methods
  • IntraUterine System ("IUS")

Hormonal contraception