A systematic search of medical literature pertaining to contraception
was performed during November 2007. The search was limited to human
subjects and journals in English language and included PubMed, UpToDate®,
and the American College of Obstetricians and Gynecologists Practice
Unintended pregnancy is a major public health problem worldwide.
The overwhelming evidence that oral contraceptives are effective
for reversible birth control has led to their widespread use in preventing
pregnancy. Despite the availability of many contraceptive options,
unplanned pregnancy rates remain high even in developed countries.
The need for effective contraceptive methods with few side effects
has led to a myriad of dose options and delivery systems.
Oral contraception pills (OCPs) were first introduced in the
United States by the Food and Drug Administration (FDA) in the early
1960s for the control of irregular menses and infertility. Early preparations
contained high estrogen and progestin concentrations, which were
later found to result in adverse effects including weight gain,
acne, and bloating and thus led to a high rate of discontinuation.
The risk of cardiovascular events including stroke, myocardial infarction,
and pulmonary embolism was not recognized until well after the approval
of OCPs.1 Safety concerns and the adverse side effects
associated with high dose formulations have led to the development
of OCP preparations with low doses of estrogen and progestin. Preparations
containing more than 50 mcg of estrogen are no longer marketed in
the United States as a result of the increased risk of thrombosis
with higher doses. A variety of progestins, in a range of doses,
have been developed in an effort to reduce side effects related
to cardiovascular risks and also to reduce androgenic effects related
to various progestins.2 As a result of improved safety
and efficacy, the age limit for OCP use, previously defined as less than
35 years for smokers and less than 40 years for nonsmokers, has
recently been lifted by the FDA.3 Currently, OCPs may be
considered as an effective option for birth control until menopause
in all healthy, nonsmoking women.
Primary care providers are often called upon to recommend contraceptive
therapy for birth control. Appropriate use requires a basic knowledge
of the pharmacology, indications, contraindications, efficacy, and
the noncontraceptive benefits of OCPs. Making a choice of the many therapeutic
options requires consideration of the specific progestins, dosing
intervals, and delivery systems available for contraception.
A thorough medical, social, and family history of the patient
is important prior to the recommendation of hormonal contraception.
Absolute and relative contraindication to the use of OCPs should
be identified. On review of systems, the physician may identify
an opportunity to choose particular hormones that provide potential
benefits in addition to contraception (Table 28-1).
Table 28-1. Potential
Noncontraceptive Benefits with Oral Contraceptives