Unintended pregnancies are a worldwide problem but disproportionately impact developing countries. Studies estimate that 40% of the 213 million pregnancies that occurred in 2012 were unintended. Globally, 50% ended in abortion, 13% ended in miscarriage, and 38% resulted in an unplanned birth. It is important for primary care providers to educate their patients about the benefits of contraception and to provide options that are appropriate and desirable for the patient.
A. Combined Oral Contraceptives
1. Efficacy and methods of use
Combined oral contraceptives have a perfect use failure rate of 0.3% and a typical use failure rate of 8%. Their primary mode of action is suppression of ovulation. The pills can be initially started on the first day of the menstrual cycle, the first Sunday after the onset of the cycle, or on any day of the cycle. If started more than 5 days after the first day of the cycle, a backup method should be used for the first 7 days. If an active pill is missed at any time, and no intercourse occurred in the past 5 days, two pills should be taken immediately and a backup method should be used for 7 days. If intercourse occurred in the previous 5 days, emergency contraception should be offered, and the pills restarted the following day. A backup method should be used for 5 days.
2. Benefits of oral contraceptives
Noncontraceptive benefits of oral contraceptives include lighter menses and improvement of dysmenorrhea symptoms, decreased risk of ovarian and endometrial cancer, and improvement in acne. Functional ovarian cysts are less likely with oral contraceptive use. The frequency of developing uterine myomas is lower in patients who have taken oral contraceptives for longer than 4 years. There is also a beneficial effect on bone mass.
3. Selection of an oral contraceptive
Any of the combination oral contraceptives containing 35 mcg or less of ethinyl estradiol or 3 mg of estradiol valerate are suitable for most women. There is some variation in potency of the various progestins in the pills, but there are essentially no clinically significant differences for most women among the progestins in the low-dose pills. There is insufficient evidence that triphasic oral contraceptives provide any benefit compared to monophasic oral contraceptives in terms of effectiveness, bleeding patterns or discontinuation rates. Therefore, monophasic pills are recommended as a first choice for women starting oral contraceptive use. Women who have acne or hirsutism may benefit from treatment with desogestrel, drospirenone, or norgestimate, since they are the least androgenic. A combination regimen with 84 active and 7 inert pills that results in only four withdrawal bleeds per year is available. There is also a combination regimen that is taken continuously with withdrawal bleeds. At the end of 1 year of use of this ...