CONTRACEPTION UPDATE
Highlights from the 51st Annual T. Hart Baker, MD, Obstetrics and Gynecology Symposium, presented by Southern
California Permanente Medical Group, Las Vegas, NV
Anita Nelson, MD, Professor, Department of Obstetrics and Gynecology, David Geffen School of Medicine at the
University of California, Los Angeles, and Chief, Women’s Healthcare Programs, Harbor-UCLA Medical Center,
Torrance, CA
| Introduction: speaker believes many myths, beliefs, and attitudes about mammography and prenatal
care apply to pregnancy prevention; only intended and unintended pregnancies tracked; intended pregnancy
considered that which is not unintended; almost 49% of all pregnancies unintended; patients restricted
from higher-tier methods of contraception in some settings until oral contraceptives (OCs) fail
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| Tiers of contraceptive efficacy
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 | Top tier: implants, intrauterine devices (IUDs), monthly injections; failure rate <1%; implants least used
method in United States; medroxyprogesterone acetate (DMPA [eg, Depo-Provera]) failure rate 3%
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| Second tier: combined hormonal methods; failure rate 8%
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| Third tier: barrier and behavior methods; condoms at top of third tier; failure rate ≈15% (18% for adolescents);
spermicides least effective method
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| Etonogestrel contraceptive implant: effective 3 yr; no pregnancies in clinical trials; Physicians’ Desk Reference
states pregnancy rate of 0.38% (attributed to patient being pregnant before implant inserted or inadvertently
not inserted); Food and Drug Administration attributes any conception occurring within 2 wk
of stopping method to be failure of that method; rapid return to fertility; mechanism of action—ovula-tion
suppression; thickens cervical mucus; contains low levels of progestin; contraindications—patient with
breast cancer or breast cancer within last 5 yr; drug interaction with cytochrome P450 (efficacy affected);
rare medical contraindications; side effects—unpredictable bleeding patterns; acne in 0.1% of women
with no acne before using method; significant improvement in 60% of women with moderate to severe
acne; no difference in weight gain compared to women using nonmedicated IUD; good method for many
women with serious medical problems in which other methods contraindicated
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| Copper IUD: copper T 380 device marketed in 1988 under strict regulation; highly effective, especially if
conception not recommended (eg, breast cancer, autoimmune diseases); approved for use <10 yr; IUD
most cost-effective contraceptive method; not abortifacient (ova recovered from women using IUD not
fertilized); failure rates—data show no pregnancies in women using <20 yr; risk for expulsion reduced
by 50% if not inserted during menses; data show prophylactic use of nonsteroidal anti-inflammatory
drugs (NSAIDs; for pain and bleeding) did not reduce removal rates; risk for infection and pelvic inflammatory
disease (PID) associated with early colonization of uterus; infection develops in ≈1 in 1000
women; insertion no longer contraindicated by—presence of bacterial vaginosis (BV) or yeast infection
(oral therapy recommended if patient has BV); history of PID; infected abortion in past 3 mo; unresolved
abnormal Papanicolaou (Pap) test; untreated vaginitis; increased susceptibility to infection (eg, AIDS,
leukemia); genital actinomycosis; contraindications to insertion—behavior suggesting high risk for PID;
postabortion endometritis; known or suspected uterine or cervical malignancy
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| Levonorgestrel-releasing intrauterine system (LNG IUS): option for women considering tubal sterilization
(less risky and reversible) or endometrial ablation for bleeding; failure rate—first-year failure rates
equivalent to those of copper IUD; potential side effects—considerable amount of unpredictable spotting
and bleeding first few months after insertion; at 4 mo, same number of bleeding days, but significantly
less blood loss; by 12 mo, mean bleeding days zero; menorrhagia—LNGIUS indicated in some countries
(not in United States) for treatment of menorrhagia; effective treatment for inherited bleeding disorders;
data show more effective in treating menorrhagia than are NSAIDs and antifibrinolytic agents; according
to Cochrane Database systematic review, as effective as ablation in controlling menorrhagia; data support
use as alternative to hysterectomy
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| Medroxyprogesterone acetate (DMPA; Depo-Provera): highly effective; good method for women with
seizure disorders (maintains therapeutic level despite interaction with anticonvulsants; slight anticonvulsant
effect); potential side effects—one double-blind placebo-controlled study showed no increase in
weight from baseline and no difference in weight gain between users of DMPA and those receiving placebo
injection, but profound weight gain observed (patient should be counseled about possible weight
gain); concerns about bone mineral density (BMD)—2004 “Black Box” warning states DMPA should be
used >2 yr only if other methods inadequate; American College of Obstetricians and Gynecologists’
(ACOG) position is that concerns about BMD should not restrict initiation or continuation of DMPA in
adults or teens; adequate calcium intake should be encouraged
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| DMPA administration protocol: quick start or same-day start endorsed; offer patient emergency contraception
(EC; Plan B) if indicated (ie, unprotected intercourse within last 5 days); administer DMPA
and advise use of backup method for 7 days; obtain pregnancy test or repeat test in 2 to 3 wk; 40% of
pregnancies in women using DMPA not diagnosed until second trimester; DMPA does not adversely
affect fetus, but delays diagnosis of pregnancy
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| Lower-dose DMPA (DMPA-SC): new formulation (new concentration and new buffers); 104 mg/0.65
mL; administered subcutaneously every 14 wk (provides extra month per year in same number of injections);
potential for self administration; approved for treatment of endometriosis pain (reduction in
pain score same as with gonadotropin-releasing hormone [GnRH] agonist); zero pregnancies in 20,000
woman-cycles of exposure; efficacy not affected by body mass index (BMI)
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| Oral contraceptives: only 30% of women using prescribed OCs by third cycle; body weight and OC
failure—data show women in upper quartile of weight more likely to have OC failure with low-dose
formulation; recommend shortening of pill-free interval, rather than prescribing higher-dose formulation;
hormone withdrawal symptoms—data show no increase in many hormone-related side effects associated
with OCs; data show 3 times as many problems during hormone-free interval than during
active-pill week; drospirenone (24/4 dosing regimen) shown effective for symptoms of premenstrual
dysphoric disorder; new develop-ments—extended or continuous use; quick start and first-day start
each cycle
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| Quick-start protocol: evidence that with conventional start, up to 25% of women do not fill prescription
(particularly adolescents); start with first pill in pack; provide EC if indicated; provide backup method
for 7 days; data show by third cycle, 54% of women missing >2 pills every cycle
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| Transdermal contraceptive systems (patches): failure rate—30% of pregnancies occurred in 3% of
women weighing >198 lb; data show compliance higher than with OCs; extended use possible (speaker
less enthusiastic about extended use for patch); no long-term data on episodic use or “use for indication”;
pharmacokinetic profile for patch—different from pharmacokinetic profile for OCs; serum level of estrogen
in patch 60% higher than in OCs, but peak concentration 25% lower (misses intestinal first-pass metabolism);
no convincing evidence of increased thrombosis; ACOG guidelines do not recommend
estrogen-containing methods of birth control for women >35 yr of age with BMI >30
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| Contraceptive vaginal rings: once-a-month method; easily placed by woman; discreet; lowest estrogen
dose among combined hormonal methods; constant serum concentrations; avoid gastrointestinal interference
with absorption; avoid hepatic first-pass metabolism; patient concerns—associated pain, displacement,
partner’s ability to sense; can be placed anywhere in vagina; cycle control better than with
comparator OC (Nordette 28); can initiate quick-start and extended cycles; increase in vaginal discharge;
2 studies show decrease in recurrence of BV
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| Condoms: marketing targeting women; array of choices in sizes and characteristics (eg, flavors, scents, colors,
textures, climax control); polyurethane condoms recommended if woman using antifungal agents
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| Lea’s shield: no fitting needed; prescription only (available over-the-counter in Europe); one-way valve
allows exit for cervical secretions and air
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| FemCap: 2 sizes (eg, parous and nulliparous); spermicide applied inside bow; clinical trials looking at
microbicides on brim of cap
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| Contraceptive sponge: discreet and less messy than other spermicides
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| Cycle beads: color-coded string of beads; helps woman identify days of cycle when pregnancy likely and
unlikely; mechanism easy to understand
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| Emergency contraception: single-dose regimen recommended vs 2-dose regimen taken within 12 hr; can
be taken up to 120 hr after unprotected intercourse; provide prescription in advance; more effective when
taken sooner; data support concept that EC has little or no effect on postovulation event, but highly effective
when taken before ovulation
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Suggested Reading
Holt VL et al: Body mass index, weight, and oral contraceptive failure risk. Obstet Gynecol 105:46, 2005;
Jick S et al: Further results on the risk of nonfatal venous thromboembolism in users of the contraceptive
transdermal patch compared to users of oral contraceptives containing norgestimate and 35 microg of ethinyl
estradiol. Contraception 76:4, 2007; Marjoribanks J et al: Surgery versus medical therapy for heavy
menstrual bleeding. Cochrane Database Syst Rev 10:DC003855, 2006; Potter LS: How effective are contraceptives?
The determination and measurement of pregnancy rates. Obstet Gynecol 88:13S, 1996; Lahteenmaki
P et al: BMJ 316:1122, 1998; Nelson AL: Contraindications of IUD and IUS use: Contraception
75:S76, 2007; Novikova N et al: Effectiveness of levonorgestrel emergency contraception given before or
after ovulation—a pilot study. Contraception 75:112, 2007; Sulak PJ et al: Hormone withdrawal symptoms
in oral contraceptive users. Obstet Gynecol 95:261, 2000; Sivin I: Utility and drawbacks of continuous
use of a copper T IUD for 20 years. Contraception 75:S70, 2007; Stewart FH et al: Extended use of transdermal
norelgestromin/ethinyl estradiol: a randomized trial. Obstet Gynecol 105:1389, 2005.
Educational Objectives
| The goal of this program is to present evidence supporting the use of contraceptive options. After hearing
and assimilating this program, the clinician will be better able to:
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| 1. Discuss reasons why women may not use contraception for pregnancy prevention.
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| 2. Identify contraceptive methods that comprise the top tier of efficacy.
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| 3. Counsel patients about contraceptive options.
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| 4. Discuss mechanisms of action, potential side effects and noncontraceptive benefits associated with
some contraceptives.
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| 5. Describe new approaches to older contraceptive methods.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and planning committee members
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 has received research
grants from Barr (Duramed), Bayer Healthcare (Berlex), and Wyeth Pharmaceuticals, and either acts as a consultant or is on the
advisory board for Barr, Bayer, and Wyeth. Dr. Nelson has received honoraria or is on the Speaker’s Bureaus of Barr, Bayer,
and Wyeth. The planning committee reported nothing to disclose.
Acknowledgment
Dr. Nelson was recorded at the 51st Annual T. Hart Baker, MD, Obstetrics and Gynecology Symposium, sponsored by
Kaiser Permanente Southern California and held on November 9-10, 2007, in Las Vegas, NV.
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