Contraception, Oral, Injections, & Implants

Key Features

General Considerations

• 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

• Primary care providers need to educate their patients about the benefits of contraception and to provide them options that are appropriate and desirable

Treatment

Medications

Oral contraceptives

• Combination pills

  • Have a theoretical failure rate of only 0.3% if taken absolutely on schedule but a typical use failure rate of 8%

  • Primary mode of action is suppression of ovulation

  • Pills can be started on the first day of the menstrual cycle, on the first Sunday after the onset of the cycle, or on any day of the cycle

    • If started on any day other than the first day of the cycle, a backup contraceptive method should be used

    • The combination pill is taken daily for 21 days, followed by 7 days of placebos or no medication, and this schedule is continued for each cycle

    • 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 contraceptive method should be used for 7 days

    • If an active pill is missed at any time, and intercourse occurred in the previous 5 days, emergency ("Plan B") contraception should be used immediately, and the combination pills restarted the following day; a backup contraceptive method should be used for 5 days

  • Another regimen involves taking a combination pill continuously with no regular menses; at the end of one years' use, 58% of the women had amenorrhea, and nearly 80% reported no bleeding requiring sanitary protection

  • Studies have not shown any significant risk from long-term amenorrhea for patients taking this continuous oral contraceptive regimen

Benefits

• There are many noncontraceptive advantages to oral contraceptives

  • Menstrual flow is lighter

  • Decreased risk of ovarian and endometrial cancer

  • Improvement in acne

  • Dysmenorrhea, pain with ovulation and postovulatory aching are relieved for most women

  • Functional ovarian cysts generally disappear with oral contraceptive use, and new cysts do not occur

  • Frequency of uterine myomas is lower in long-term users (> 4 years)

  • There is also a beneficial effect on bone mass

• Selection

  • Any of the "low-dose" 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 low-dose pills, but this variation results in essentially no clinically significant differences for most women

  • Women who have acne or hirsutism may benefit from use of one of the pills containing the ...