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Contraception
Kim Michal Stein, MD
Melissa J. Fullerton, MD
image BASICS
DESCRIPTION
  • Medications or procedures that control timing of pregnancies and prevent unintended pregnancies
  • Contraception options are divided into two major categories: hormonal and nonhormonal.
  • The most effective methods of contraception are vasectomy, female sterilization, and the long-acting reversible contraceptives (LARCs).
EPIDEMIOLOGY
Incidence
  • The estimated prevalence of contraception use among reproductive age women is 63% worldwide and 77% in the United States (1).
  • 49% of all pregnancies in the United States are unintended, and half occur in women using a form of reversible contraception.
  • 43% of all unintended pregnancies in the United States result in termination.
  • The most frequently used forms of contraception in the United States (in order of prevalence) are oral contraceptive pills (OCPs), female sterilization, male condom, male sterilization, and depot injectables.
  • Although LARCs are one of the most effective forms of contraception, they are among the least used methods in the United States.
RISK FACTORS
  • Unintended pregnancy: higher rates among women ages 18 to 24 and >40 years, unmarried/cohabitating women, women with less than a college education, and minority women
  • Contraception discontinuation or nonuse: patient or partner dissatisfaction with prior methods of contraception or intolerable side effects
image DIAGNOSIS
DIAGNOSTIC TESTS & INTERPRETATION
  • A negative pregnancy test (urine or serum) is advised prior to initiating contraception.
  • Testing for gonorrhea and chlamydia should be considered but is not required prior to IUD insertion, although need to rule out symptomatic infections.
  • Pap smear if otherwise indicated
  • Screen for hypertension [A].
  • In family history of thrombophilia, testing can be considered before initiation of estrogen-containing contraception, especially if specific defect is known.
image TREATMENT
GENERAL MEASURES
  • Methods should be selected based on patient preference, effectiveness, desire for sexually transmitted disease (STD) prevention, side effects, and contraindications.
  • General categories included hormonal and nonhormonal methods.
    • Nonhormonal methods include condoms, diaphragm, cervical cap, copper IUD, vasectomy, female sterilization, fertility awareness, sponge, spermicides, and abstinence.
    • Hormonal methods include combined oral contraceptives (COCs), patch, ring, injectables, intrauterine devices (IUDs), and implants.
MEDICATION
  • Estrogen-progestin contraceptives
    • Mechanism of action: Work by suppression of ovulation, thickening cervical mucus, and endometrial changes that interfere with transport of sperm to egg and with implantation
    • Efficacy: failure rate of about 4.8% at 1 year
    • Side effects: nausea, bloating, headaches, mastalgia, depression, acne, and hirsutism
    • Side effect management: Breakthrough bleeding is usually self-limiting after 3 months; if persists, change pill. Amenorrhea: rule out pregnancy
    • Combined oral contraception (COCs): Pill
      • All COCs contain the same type of estrogen (ethinyl estradiol) but differ in the level of estrogen (range of 10 to 50 &mgr;g) and the type of progestin
      • Newer progestins (such as norgestimate and desogestrel) are less androgenic but may have increased rate of venous thromboembolism (VTE).
      • Start with a pill that is inexpensive (generic); contains an average amount of estrogen (30 to 35 &mgr;g).
      • Dosing: Most pills have a 21/7 regimen (21 active days and 7 placebo). Alternatively, can take active pills continuously with four yearly scheduled withdrawal bleeds.
      • Initiation: first day start (begin the pill on the first day of menses), quick start (begin pill on day medication is obtained), or Sunday start (begin pill on first Sunday)
      • Weekly hormonal patch (Ortho Evra): releases 20 &mgr;g/day ethinyl estradiol and 150 &mgr;g/day norelgestromin
      • Applied transdermally and changed weekly
      • Produces higher serum estrogen levels than oral 20 &mgr;g pill and may be associated with a slightly increased risk of blood clot
      • Patch may cause local skin irritation; not as reliable in women >90 kg.
    • Vaginal contraceptive ring (NuvaRing):
      • Flexible polymer ring with 15 &mgr;g/day of ethinyl estradiol and 120 &mgr;g/day of etonogestrel absorbed via vaginal wall
      • Inserted into vagina for 3 weeks/cycle or use continuous cycling for 4 weeks then replace immediately with a fresh ring (off label)
      • Though systemic exposure to estrogen is about 50% of exposure with COCs, the risk of blood clots is about the same.
  • Progestin-only birth control
    • Mechanism of action: thickening cervical mucus and thinning endometrial lining
    • Progestin-only pill (Micronor)
      • Efficacy: failure rate of about 0.3% with perfect use, 9% with typical use at 1 year
      • Can be used in women with contraindication for estrogen, including breastfeeding women after 6 weeks postpartum.
      • Dosing: 1 pill taken daily, no placebo days; needs to be taken at the same time daily
      • Side effects: irregular bleeding
    • Injectable contraceptive (medroxyprogesterone)
      • Efficacy: failure rate of 0.2% with perfect use, 6% with typical use at 1 year
      • Dosing: Depo-Provera 150 mg IM or Depo-SubQ Provera 104 mg SQ, both are given every 3 months. Contraceptive levels of hormone persist for up to 4 months (2- to 4-week margin of safety).
      • Side effects include irregular bleeding, weight gain (average of 5 lb/year of use), and amenorrhea.
  • LARCs: IUDs and implantable devices [A]
    • Mirena (levonorgestrel IUD):
      • Mechanism of action: sterile inflammatory reaction due to foreign body that is toxic to sperm and ova, thickens cervical mucus, endometrial decidualization and glandular atrophy, inhibiting sperm-egg binding, partial inhibition of ovarian follicular development and ovulation
      • Efficacy: failure rate of 0.2% with both perfect and typical use at 1 year
      • Dosing: IUD releases 20 &mgr;g/day of levonorgestrel (very low serum levels).
      • Approved for use up to 5 years; has been used off label for up to 7 years
      • Safe in nulliparous women/teenagers
      • Can be inserted immediately postpartum or immediately following dilation and curettage for miscarriage or abortion, but these are associated with higher rates of expulsion compared to delayed placement (6 to 10 weeks)
      • Side effects: irregular menstrual spotting for the first 3 to 6 months that usually resolves after 6 months of use; may see absence of menses after 1 year
      • Side effect management: Consider trial of COCs or estrogen alone for spotting and cramps.
      • Can reduce heavy bleeding in women with menorrhagia
    • Skyla (levonorgestrel-releasing intrauterine system):
      • Similar to Mirena but releases lower hormone dose (14 &mgr;g/day initially, down to 5&mgr;g/day
        P.227

        of levonorgestrel), slightly smaller, and lasts 3 years. Smaller insertion tube might make this an easier IUD for nulliparous women. More bleeding days than Mirena
    • ParaGard (Copper IUD):
      • Mechanism of action: In addition to sterile inflammatory reaction due to foreign body, free copper and copper salts enhance the cytotoxic inflammatory reaction-toxic to sperm and ova.
      • Efficacy: failure rate of 0.6% with perfect use, 0.8% with typical use at 1 year
      • Approved for up to 10 years
      • Same insertion timing as Mirena
      • Side effects: blood loss and cramping
    • Nexplanon (etonogestrel implant):
      • Mechanism of action: same as progestin-only pill or medroxyprogesterone
      • Efficacy: failure rate of 0.05% with perfect use, 0.3% with typical use at 1 year
      • Dosing: 40 mm × 2 mm semi-rigid plastic rod containing 68 mg of etonogestrel. Initially releases 60 to 70 &mgr;g/day, down to 25 to 30 &mgr;g/day at the end of the third year
      • Effective for up to 3 years
      • Must be inserted only by certified providers
      • Side effects: menstrual irregularities (common first 6 to 12 months), amenorrhea after 1 year
  • Emergency contraception: should be initiated as soon as possible post-unprotected intercourse. Copper IUD is the most effective, followed by levonorgestrel, ulipristal and Yuzpe method (least effective) (2)[A]
    • Copper-bearing IUD (ParaGard): Insert up to 5 days after intercourse; failure rate of 0.04-0.19%.
    • Levonorgestrel: 1.5 mg taken as two 0.75-mg tablets (Plan B) or one 1.5-mg tablet (Plan B 1-Step). 1.1-2.4% failure rate. Less nausea than “Yuzpe regimen.” Available over the counter; may be less expensive if prescribed. Most effective within 72 hours, efficacy declines with time
    • Ulipristal acetate (Ella): 30 mg × 1 dose; Selective progesterone modulator, effective up to 5 days after unprotected intercourse with minimal decline in efficacy. About 2% failure rate
    • Estradiol/levonorgestrel (Preven, Lo Ovral, Ogestrel): “Yuzpe regimen” 50 &mgr;g/0.25 mg, 2 tablets q12h (4 tablets total). Any OC may be used as long as the dose of estrogen component ≥100 &mgr;g/dose. About 3.2% failure rate. Note: Antiemetic should be given 1 to 2 hours before each dose.
ADDITIONAL THERAPIES
  • Condoms: failure rate of 2% with perfect use, 18% with typical use at 1 year
  • Spermicides: All contain nonoxynol-9; may alter vaginal flora and mucosal barrier. 28% failure at 1 year with typical use
  • Sponge (Today Sponge): Soft foam disk contains nonoxynol-9. Moisten with water before use; effective for 24 hours; must leave in for 6 hours after use; less effective in parous women. 12-24% failure at 1 year with typical use
  • Diaphragm: dome-shaped device made of latex or silicone with flexible spring-activated rim, works by preventing sperm from entering cervix; used with spermicides. 12-16% failure at 1 year with typical use.
SURGERY/OTHER PROCEDURES
Permanent sterilization
  • Female: tubal ligation or Essure (micro-insert system placed hysteroscopically). Essure requires confirmation of tubal occlusion with hysterosalpingogram 3 months postprocedure. 0.5% failure at 1 year
  • Male: vasectomy. Less complicated than female. 0.15% failure at 1 year
COMPLEMENTARY & ALTERNATIVE MEDICINE
  • Fertility awareness methods: calendar method, cervical mucus method, temperature method. Low cost but generally not as effective as other methods. 24% failure at 1 year with typical use
  • Withdrawal method: Male partner withdraws from vagina before ejaculation. Failure if not timed accurately. 22% failure at 1 year with typical use
  • Lactational amenorrhea method: Breastfeeding is effective contraception only if (i) the infant is <6 months old, (ii) the infant is exclusively breastfeeding, and (iii) the mother has not resumed regular menses. 7% failure at 1 year with typical use
Pediatric Considerations
  • AAP and ACOG recommend LARCs as the most effective in sexually active adolescents.
  • Contraception counseling should include anticipated adverse effects, need to use condoms for STD prevention, and indications for emergency contraception (including options and how to obtain).
image ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Patient Monitoring
  • Pelvic exam, Pap smear, and STI testing per guidelines and routine follow-up 2 to 3 months postinitiation of all methods to assess tolerance
  • Check for IUD strings 1 month after insertion; spontaneous expulsion rate highest in the first month.
  • BP check within 3 months of initiation in patients on estrogen containing methods
DIET
St. John's wort may alter estrogen levels, reducing efficacy or causing breakthrough bleeding.
PATIENT EDUCATION
  • Diaphragm: device inspected prior to each use, 1 tablespoon of spermicide in hollow of the dome, diaphragm is inserted into the vagina, additional applicator of spermicide placed in vagina. If placed >6 hours prior to intercourse need additional applicator of spermicide. Position needs to be checked post intercourse, and additional spermicide applied prior to each new episode of intercourse. Diaphragm should remain in place for at least 6 hours after the last episode of intercourse to maximize effectiveness.
  • Male condoms: New condom is placed on the penis before genital contact, remains intact until the penis is withdrawn, new condom needs to be used with every act of intercourse.
  • IUD: Patient should monitor presence of the string monthly following menses.
  • OCP: Pill should be taken at approximately the same time each day. Back up birth control method is needed for the first 7 days with quick start and Sunday start methods.
REFERENCES
1. Alkema L, Kantorova V, Menozzi C, et al. National, regional, and global rates and trends in contraceptive prevalence and unmet need for family planning between 1990 and 2015: a systematic and comprehensive analysis. Lancet. 2013;381(9878):1642-1652.
2. Cheng L, Gülmezoglu AM, Piaggio G, et al. Interventions for emergency contraception. Cochrane Database Syst Rev. 2008;(2):CD001324.
3. van Hylckama Vlieg A, Helmerhorst FM, Vandenbroucke JP, et al. The venous thrombotic risk of oral contraceptives, effects of oestrogen dose and progestogen type: results of the MEGA case-control study. BMJ. 2009;339:b2921.
Additional Reading
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  • CDC Medical Eligibility Criteria for Contraceptive Use, 2010. Available as chart, app for smartphone (“CDC Contraception”)
  • Chart comparing contraceptive methods: ARHP Method Match at http://www.arhp.org/methodmatch/
Codes
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ICD10
  • Z30.9 Encounter for contraceptive management, unspecified
  • Z30.41 Encounter for surveillance of contraceptive pills
  • Z30.431 Encounter for routine checking of intrauterine contracep dev
Clinical Pearls
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  • Hormonal and IUD contraceptives may be initiated immediately if the likelihood of pre-existing pregnancy is low.
  • Contraception method should be chosen based on individual patient needs.
  • LARC methods provide high efficacy and convenience for patients.
  • All patients should be counseled on emergency contraception options.