CONTRACEPTION UPDATE
Anita L. Nelson, MD, Professor of Obstetrics and Gynecology, David Geffen School of Medicine at the University of
California, Los Angeles
Educational Objectives
| The goal of this program is to review current methods of contraception. After hearing and assimilating this program,
the clinician will be better able to:
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 | 1. Identify contraceptive methods in the top tier of efficacy.
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| 2. List contraindications for the placement of copper intrauterine devices (IUDs).
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| 3. Describe the mechanisms of action of IUDs and the levonorgestrel intrauterine system.
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| 4. Discuss risks and side effects of oral contraceptives.
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| 5. Counsel patients about condoms, female barrier methods, and emergency contraception.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of
the planning committee to disclose relevant financial relationships within the past 12 months that might create
any personal conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity
promotes quality in health care and not a proprietary business or commercial interest. For this program, the following
has been disclosed: Dr. Nelson received research grants from Barr (Duramed), Bayer Healthcare (Berlex),
and Wyeth Pharmaceuticals, and is on the Speakers’ Bureau and/or has received honorarium from Barr,
Bayer, Digene, Esprit Pharmaceuticals, Merck & Co., Organon, Ther-Rx, and Wyeth. Dr. Nelson is a consultant
and/or is on the advisory board for Barr, Bayer, Organon, and Wyeth. The planning committee reported nothing
to disclose.
Acknowledgements
Dr. Nelson spoke in Carlsbad, CA, at the 35th Annual Irving M. Rasgon, MD, Family Medicine Symposium, presented
June 27-29, 2008, by Kaiser Permanente. The Audio-Digest Foundation thanks Dr. Nelson and Kaiser Permanente
for their cooperation in the production of this program.
| Diabetes and birth defects: sacral agenesis—pathognomonic for diabetes; 242-fold increased risk with diabetes;
child unable to walk or control bowel or bladder function; neural tube and cardiac defects more common
among diabetics; congenital anomaly rate in liveborn term infants—with reasonably good glucose control, 9.9%;
with tight glucose control (fasting, 90-100 mg/dL; 2-hr postprandial glucose, <120 mg/dL) in first trimester,
≈6%; when glucose controlled before conception, major congenital anomaly rate lower in diabetics than in
general population; planning and preparation important; in California, 40% of pregnancies among diabetic
women unplanned
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| Failure rates of contraceptive methods: National Survey of Family Growth—medroxyprogesterone (eg, Depo-
Provera) found to have nearly 7% failure rate; oral contraceptives (OCs), nearly 9% (in typical use; after 3
menstrual cycles, 54% of women miss ≥3 pills); condoms, 17.4%; newer fertility awareness methods, ≈25%;
pregnancy rate in women not planning pregnancy and not using contraception, 85% (43% of women “didn’t
think they could get pregnant”); recognize ambivalence, motivation (eg, partner’s motivation to use condoms),
and access problems; retail pharmacy data—75% of women returned for first refill; for 12 mo, highest
follow-through 34%
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| Tiers of contraception efficacy: top tier—<1% pregnancy rate in typical use; implants; intrauterine devices
(IUDs); least commonly used; second tier—7% to 10% failure rate; combined hormonal methods; medroxyprogesterone;
no evidence of lower failure rates with contraceptive vaginal rings or transdermal systems;
considerations—switching from estrogen-containing pills to progestin-only pills (norethindrone [eg, Ortho Micronor;
0.35 mg] as effective as combined OCs); find method most likely to be used; medical indications;
how soon woman wants to have child; lifestyle issues; likelihood of partner to use condom; preferences; education
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| Etonogestrel implant (Implanon): recently approved for Medicaid coverage; highly effective; rapidly reversible;
contraindicated in women with breast cancer in last 5 yr, pregnant women, and women taking drugs
that increase cytochrome P450 ; inhibits ovulation while maintaining high levels of estrogen; ovulation suppressed
for 30 mo (after 30 mo, cervical mucus prevents pregnancy); due to low levels of progestin, vulnerable
to St. John’s wort, phenobarbital, and phenytoin (Dilantin); estrogen levels same as in follicular phase (no
concerns about effects on bones); side effects—unpredictable bleeding patterns; acne occurred in ≈14% of
women (60% of women who initially presented with acne had either complete resolution or improvement); in
1-yr study, 13% of women had headache; implantation—takes 1 min (2-3 min for removal); firm rod; “push
down on one end, the other one stands straight up (for removal)”
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| Intrauterine devices: consider contraindications, risks, and benefits (eg, copper IUD or levonorgestrel intrauterine
system [IUS] may be placed in women with hypertension; HIV not contraindication)
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| ParaGard T 380A: copper IUD available since 1988; approved for use up to 10 yr (recent data support use for
up to 20 yr); to reduce risk for expulsion, avoid inserting during menses; no increased risk for pelvic inflammatory
disease (PID), except in first 20 days after placement (rule out infection before placement; antibiotic
prophylaxis not warranted); mechanism of action—when serum β-human chorionic gonadotropin ( β-
hCG) measured, no rise and drop (“that would indicate an abortion”) seen; when uterine cavity flushed,
“you don’t get fertilized egg”; supporting evidence of absence of sperm upstream (ie, copper functional
spermicide); in study, fertilization rate in women who presented with no method of contraception and mid-
cycle sexual intercourse, 50% (<20% pregnancy rate; 60% of conceptions lost before implantation);
contraindications—suspected cancer or cancer; pregnancy; infection; distorted uterus; uterus too large or too
small for placement; Wilson’s disease (for copper IUDs); cost-effective (every copper IUD offered to
woman saves health care system ≈$14,122 over 5 yr)
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| Levonorgestrel IUS: licensed in 106 countries (also approved for treatment of heavy bleeding in 103); as effective
as copper IUD; bleeding—during first month, more days of spotting and bleeding than no bleeding
can be expected; number of bleeding days normalizes by 4 mo; 20% of women have no spotting or bleeding
by 12th month; median number of days of bleeding, 0; most women have 1 to 3 days of spotting; mechanism
of action—thick cervical mucus due to local progestin; causes atrophy of endometrial lining; does not
inhibit ovulation (important if patient on warfarin [eg, Coumadin] therapy or suffers from mittelschmerz);
“she still has her own estrogen and own cycling”; amenorrhea due to high concentrations of levorgestrel in
endometrium; efficacy—more effective than prostaglandins and antifibrinolytic agents; equivalent to endometrial
ablation after first year; inexpensive, easy to perform, and reversible; study—women who qualified
for hysterectomy due to excessive bleeding randomized to levonorgestrel IUS or hysterectomy; after
5 yr, 58% of women with IUS did not need hysterectomy
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| Depo-Provera: Depo-Sub Q Provera 104 given every 12 to 14 wk; clinical applications—reduces sickle cell
crises by 70% in patients with sickle cell anemia; no drug–drug interactions (useful for patients with seizure
disorders; progestin also anticonvulsant); reduces adolescent pregnancy and when given to postpartum adolescents,
reduces high rate of recidivism; side effects—counsel patients; more women gain weight than maintain
or lose weight; according to American College of Obstetricians and Gynecologists (ACOG), current
evidence about use of Depo-Provera and skeletal health do not restrict initiation or continuation of Depo-
Provera use in adults or teenagers; do not perform dual-energy x-ray absorptiometry (DEXA) to determine
whether patient candidate for continued use; administration—same-day start suggested; determine whether
woman had unprotected intercourse in last 5 days (if yes, give emergency contraception and Depo-Provera);
onset of Depo-Provera, 7 days (provide condoms for 7 days); if woman had unprotected intercourse during
month, repeat urinary chorionic gonadotropin (UCG) in 2 to 3 wk; Depo-Sub Q Provera 104—highly effective;
not affected by body weight; approved for treatment of pain due to endometriosis; support lines important
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| Oral contraceptives: body weight—no consistent relationship between dose and failure; higher failure rates
seen among heavier women, but “do not give them higher doses”; according to ACOG, since obesity and
age independent risk factors for thrombosis, women >35 yr of age with body mass index (BMI) >30 should
generally not be given estrogen-containing contraceptives; in England, women with BMI ≥40 never offered
any estrogen-containing agent due to risk for thrombosis; breast cancer—in reproductive-age women, OCs
do not increase risk for breast cancer; noncontraceptive benefits—certain brands approved for treatment of
acne; in placebo-controlled trial, 18.4% of women using OCs for 6 mo reported headaches, compared to
20.5% in placebo group; no hormonally-related side effect occurred at higher incidence in OC group, compared
to placebo group
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| Pill-free interval or placebo: original pill contained 9.85 mg of norethindrone and 150 µg of estrogen (scheduled
withdrawal bleeding acted as pregnancy test); elimination of placebos or shortening pill-free interval
considered; 7-day placebo results in loss of follicular control (restarting OC on day 4 or 5 results in better
control of gonadotropins, estradiol, and inhibin B); ethinyl estradiol and drospirenone (YAZ) approved by
Food and Drug Administration (FDA) to treat premenstrual dysphoric disorder (PMDD; as effective as selective
serotonin reuptake inhibitors [SSRIs]); data show no increase in risk for hyperkalemia with
spironolactone derivative (if patient on high-dose daily nonsteroidal anti-inflammatory drug [NSAID],
measure potassium 2 wk after starting OC); disadvantages of scheduled bleeding include anemia and pain
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| Quick-start protocol: start first pill in pack same day; if woman had sex night before, give 2 doses of
levonorgestrel (Plan B) and start first pill in pack same night or next morning; onset within 7 days (give 7
days of backup contraception); no increased incidence of bleeding or spotting; no problem if patient happens
to be pregnant or becomes pregnant before onset of efficacy (pregnancy indicated by lack of withdrawal
bleeding); higher 3-mo compliance
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| Transdermal systems: eg, estradiol transdermal system and norelgestromin/ethinyl estradiol transdermal system;
not given to women who weigh >198 lb; women of all ages more likely to be successful with once-
weekly method, compared to daily OC; extended use—eg, >3 mo; speaker admits “I’m a little reluctant”; little
data available
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| Etonogestrel and ethinyl estradiol vaginal ring (NuvaRing): used once monthly; low levels of hormones;
results in good cycle control; easy to use; no gastrointestinal (GI) interference; no first-pass hepatic effect; inserting
sample and demonstrating use helpful; 50% less estrogen exposure, compared to 30-µg OC pill; ring
must be removed 21 days after placement (new ring must be inserted 1 wk later; withdrawal bleeding not required
for up to 1 yr); increases lubrication and reduces rate of recurrent bacterial vaginosis
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| Condoms: inexpensive; readily available; protect against most sexually transmitted diseases (STDs); reduce
risk for cervical dysplasia; polyurethane condoms—alternative for users with latex allergy; must be used every
time woman uses vaginal treatment (eg, clindamycin creams; metronidazole [MetroGel-Vaginal] only exception);
available brand names include Avanti and Trojan Supra; 6.6% of men do not fit comfortably into normal-sized
condoms (extra-large sized condoms and condoms with snugger fit available); condoms available
with lubricants, flavors, vibrating rings, and desensitizing agents; condoms often marketed to women
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| Female barrier methods: Lea’s shield—available in one size; silicone; one-way valve allows secretions and
air to exit; available over-the-counter in Europe and by prescription in United States; FemCap—available in 3
sizes (based on nulliparity or history of vaginal delivery); sponge—failure rate with spermicides high (≈29%)
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| Newer fertility methods: cycle beads—for natural family planning; for women with menstrual cycles 26 to 32
days; beaded band helps woman identify days of cycle when pregnancy likely (eg, red bead indicates first day
of menses; brown beads indicate “sex is allowed”; white beads indicate backup method required); Billings
method—involves touching introitus; if dry for past 2 days, likelihood of pregnancy low; same efficacy as
other methods for natural family planning
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| Emergency contraception (EC): single-dose regimen recommended for greater effectiveness and no increase
in side effects; must be used within 120 hr of unprotected intercourse; more effective when given earlier;
often given in advance; mechanism of action—ovulation suppression; investigators measured leuteinizing
hormone (LH), estradiol, and progestin in 99 women to determine where in cycle women were when pill
taken; 0 women who took EC before ovulation became pregnant (number of pregnancies expected with no
EC, 4-5); 3 women who took EC after ovulation became pregnant (number of pregnancies expected with no
EC, 3-4); no evidence of efficacy in luteal phase; 53% of women who thought they were in luteal phase
(based on last menstrual period [LMP]) were in periovulatory phase
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Suggested Reading
Alvarez F et al: New insights on the mode of action of intrauterine contraceptive devices in women. Fertil Steril 49:768,
1988; Blumenthal PD et al: Hormonal contraception. Obstet Gynecol 112:670, 2008; Burkman RT: Transdermal hormonal
contraception: benefits and risks. Am J Obstet Gynecol 197:134, 2007; Gallo MF et al: Nonlatex vs. latex male condoms
for contraception: a systematic review of randomized controlled trials. Contraception 68:319, 2003; Holt VL et al:
Body weight and risk of oral contraceptive failure. Obstet Gynecol 99:820, 2002; Huber JC et al: Non-contraceptive benefits
of oral contraceptives. Expert Opin Pharmacother 9:2317, 2008; Nelson AL et al: Initiation and continuation rates seen in 2-
year experience with Same Day injections of DMPA. Contraception 75:84, 2007; Nelson AL: Contraindications to IUD and
IUS use. Contraception 75:S76, 2007; Nelson AL: Extended-regimen contraception: effects on menstrual symptoms and quality
of life. J Fam Pract 55:S1, 2006; Nelson AL: Recent use of condoms and emergency contraception by women who selected
condoms as their contraceptive method. Am J Obstet Gynecol 194:1710, 2006; Roumen FJ: Review of the combined contraceptive
vaginal ring, NuvaRing. Ther Clin Risk Manag 4:441, 2008; Scarpa B et al: Bayesian selection of optimal rules for
timing intercourse to conceive by using calendar and mucus. Fertil Steril 88:915, 2007; Sulak PJ et al: Frequency and management
of breakthrough bleeding with continuous use of the transvaginal contraceptive ring: a randomized controlled trial. Obstet
Gynecol 112:563, 2008.
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