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Contraception

ContraceptionLARCUS MECEmergency Contraception

30-Second Snapshot

What it is:Preventing pregnancy by stopping sperm from reaching a mature ovum (most hormonal and barrier methods) or by stopping a fertilized ovum from implanting (copper IUD, and technically anything working after ovulation). Not one drug class, it's a menu of mechanisms that all interrupt the same 28-day loop at different points.

The core problem:Perfect-use efficacy and typical-use efficacy are two different numbers, and the gap between them is almost entirely user error, not drug failure. A combined pill is 99%+ effective used perfectly and only ~91% effective as actually used. An implant is 99%+ either way because there's no daily step to forget.

What you do about it:Match the method to the patient, not the patient to the method. Efficacy, adherence capacity, comorbidities, STI risk, and desire for future pregnancy all steer the choice, and the U.S. Medical Eligibility Criteria (US MEC) tells you what's safe given the patient's history.

Worth knowing

Anderson framed the whole visit as "efficacy tiers first, preference second."Methods that remove the user from the daily equation (implant, IUDs) beat methods that depend on remembering something (pills, patch, ring), which beat methods that depend on remembering something at the moment of sex (condoms, spermicide, fertility tracking). If a patient can't reliably do a daily task, don't prescribe a daily task and blame them later for the "failure."

Menstrual Cycle & Why Each Mechanism Works

You can't reason about contraceptive choice without the cycle underneath it. Every drug class on this page is blocking a specific step below.

The 28-day loop (median cycle, range 21–40 days)

Where each drug class intervenes

ComponentContraceptive action
Estrogen (EE, estetrol, estradiol valerate)Suppresses FSH, which prevents follicle recruitment and blunts the LH surge. Stabilizes the endometrium so bleeding is predictable instead of erratic.
ProgestinThickens cervical mucus (blocks sperm transport), causes endometrial atrophy (hostile to implantation), and at higher/steadier doses blocks the LH surge to suppress ovulation outright.
CopperDirectly toxic to sperm and ova. No hormones, no ovulation suppression. Works almost entirely pre-fertilization by making the uterine environment spermicidal.
The unlock

This is why dose matters within progestin-only methods.A norethindrone POP delivers just enough progestin to thicken mucus, and that's a fragile effect (hence the 3-hour missed-pill window). DMPA and the implant deliver enough progestin to reliably suppress ovulation itself, which is why they're far more forgiving of imperfect timing. Same mechanism family, very different margin for error, because the dose determines how many of the three progestin effects you actually get.

Choosing a Method - Efficacy Tiers

Ask about efficacy needs, ability to comply, medical history, STI risk, desire for future pregnancy, ability to pay, and partner involvement, then narrow using the tier below before you even get to individual products.

TIER 1

LARC

Implant, hormonal IUD, copper IUD. No daily/weekly/monthly step. Efficacy is essentially the same typical-use and perfect-use.

Failure rate: <1%for all three
TIER 2

Other Hormonal

Pill, patch, ring, DMPA injection. Highly effective if used correctly, but user-dependent.

Typical use: 3–7%(COC 7%, DMPA 4%, patch/ring 3–7%)
TIER 3

Barrier

Condoms, diaphragm, cervical cap, sponge, spermicide. Only external condoms add STI protection.

Typical use: 13–28%depending on method
TIER 4

Fertility Awareness

Tracking cycle, cervical mucus, or basal temperature to avoid intercourse near ovulation.

Highest failure rate of reversible methods
The distinction that gets tested

LARC and permanent contraception have the lowest typical-use failure rates precisely because they remove the user from the equation.When a question asks "why is the implant more effective than the pill in real-world use" the answer is adherence, not pharmacology. Both suppress ovulation; only one requires the patient to remember something every day.

Contraceptive Choice Project - why this matters beyond the exam

A study offering patients free reversible contraception with efficacy-first counseling (not preference-first) cut teen births to 6.3 per 1,000 versus 34.1 per 1,000 nationally, and cut abortions to 4.4 versus 19.6 per 1,000. LARC use in teens saved an estimated $17 for every $1 spent.The lesson Anderson pulled from this: lead with efficacy tiers when counseling, don't assume patients will decline LARC, and don't let cost or a myth about nulliparity block the most effective options.

US Medical Eligibility Criteria (MEC) & Contraindications

The US MEC is the reference for "is this method safe given this patient's history." It sorts every condition into four categories, per method, per whether you're initiating (I) or continuing (C) the method.

CategoryMeaning
1No restriction, method can be used
2Advantages generally outweigh theoretical or proven risks
3Risks usually outweigh the advantages, use only if no better option and with close follow-up
4Unacceptable health risk, do not use
Worth knowing

A complete physical exam and Pap smear are notrequired before prescribing a CHC. What you actually need is a history and a blood pressure. Students consistently overestimate the workup bar here, don't repeat that mistake on rotation.

High-yield category-4 (absolute contraindication) conditions for estrogen-containing methods

ConditionWhy it's category 4 for CHC
Smoking ≥15 cigarettes/day, age ≥35Estrogen + smoking synergistically raises MI and stroke risk
Migraine with aura, any ageEstrogen raises ischemic stroke risk on top of the aura-associated risk
BP ≥160/100 or vascular diseaseEstrogen further raises BP and clot risk
Current or recent DVT/PE, known thrombophiliaEstrogen increases hepatic clotting factor production
Current breast cancerHormone-sensitive malignancy
<21 days postpartumBaseline VTE risk is already sharply elevated postpartum
Severe (decompensated) cirrhosis, liver tumorHepatically metabolized hormones, hepatic mass risk
ACHES - stop the CHC immediately

Abdominal pain (severe) · Chest pain, cough, shortness of breath · Headache (severe), dizziness, weakness, numbness · Eye problems (vision loss, blurred vision) · Severe leg pain (calf or thigh). These map onto VTE, MI, stroke, and retinal vein thrombosis. Any one of these is an emergency evaluation, not a "let's watch it" conversation.

Progestin-only methods dodge most of this

Because progestin-only methods (POP, DMPA, implant, hormonal IUD) don't carry estrogen's clotting and vascular risk, they stay category 1 or 2 for almost everything on the table above, including smoking, migraine with aura, and history of DVT/PE. This is the single biggest reason to reach for a progestin-only method instead of just declining to prescribe anything.

Nonhormonal Barrier Methods

These matter for two reasons: they're the only OTC options for someone who can't get a prescription today, and condoms are the only method (besides abstinence) that also covers STIs.

MethodFailure (typical use)Key facts
External (male) condom13%Latex is impermeable to viruses; lambskin is not. Use water-based lubricant (Astroglide, K-Y), oil-based lubricants degrade latex. Spermicide-coated condoms add no benefit and may increase HIV vulnerability.
Internal (female) condom21%Covers labia and cervix, protects against HIV and other viruses. Higher pregnancy rate than external condoms. Never use external and internal condoms together.
Diaphragm + spermicide17%Insert up to 6h before sex, leave in ≥6h after, remove within 24h(TSS risk). Efficacy drops with more frequent intercourse.
Cervical cap (FemCap)4–29%Same spermicide requirement. Leave in place no longer than 48h. Cannot use during menses.
Spermicide alone (Phexxi)21–28%Nonoxynol-9-free, prescription vaginal pH modulator. Use within 1h before each act of intercourse. Carries cystitis risk.
Sponge (Today)14–27%Contains nonoxynol-9, OTC. Leave in ≥6h after sex, no more than 24–30h total. Cannot use during menses.
Toxic shock syndrome windows - a favorite mix-up

Diaphragm: max 24 hours in place. Cervical cap: max 48 hours. Sponge: 6h minimum after sex, max 24–30 hours total.None of these protect against STIs, including HIV. Nonoxynol-9 used more than twice daily can actually increase HIV transmission risk by irritating vaginal tissue.

Fertility awareness-based methodstrack the cycle (calendar, basal body temperature, or cervical mucus changes) to avoid unprotected sex near ovulation. They're free and non-hormonal, but require meticulous, consistent record-keeping across several cycles before they're reliable, and they fall apart with irregular cycles, which is common in adolescents, breastfeeding, perimenopause, and right after a pregnancy loss or delivery. Emergency contraception itself can delay ovulation and throw off the tracking.

Combined Hormonal Contraceptives (CHC)

Pill, patch, or ring, all delivering estrogen plus progestin, all working primarily before fertilization. With perfect use, efficacy exceeds 99%; with typical use, up to 7% experience unintended pregnancy.

Regimen types

Estrogens and progestins in use

EstrogenNotes
Ethinyl estradiol (EE)The default, available 10–50 mcg. Most modern pills use 20–35 mcg ("low-dose").
Estetrol (E4)Nextstellis only, a "native" estrogen with a different clotting-factor profile than EE.
Estradiol valerateNatazia only, four-phasic dosing with dienogest.
Progestin generationAgents
1st generation
EstranesNorethindrone, norethindrone acetate, ethynodiol diacetate
2nd generation
GonanesLevonorgestrel, norgestrel
3rd generation
Lower androgenicityNorgestimate, desogestrel (active form etonogestrel)
4th generation
Antiandrogenic / SPRM-adjacentDrospirenone, dienogest, segesterone acetate; ulipristal acetate is a separate selective progesterone receptor modulator (SPRM) used for EC, not daily contraception
Why some pills help acne and others don't

All CHCs raise sex hormone-binding globulin (SHBG) via the estrogen component, which mops up free testosterone. But older, more androgenic progestins (norgestrel, levonorgestrel) partially fight that effect. Newer, less androgenic progestins (norgestimate, desogestrel, and especially drospirenone) don't fight it, so free testosterone drops further and acne improves more. That's the mechanism behind "which pill for acne" questions, it's not magic, it's just less androgen competing with the estrogen effect.

Starting a CHC

Start methodWhenBackup needed?
First-day startDay 1 of mensesNone
Sunday startFirst Sunday after menses begins7 days if >5 days since bleeding started
Quick startDay of the office/pharmacy visit7 days (none if within first 5 days of menses)

Quick start is preferred in practice: about a quarter of patients told to "wait for your period" never actually start, whether from forgetting, an unplanned pregnancy in the interim, or simply not filling the prescription. A second method should be used for 7–30 days after CHC initiation depending on product labeling, and hormonal contraception should not resume sooner than 5 days after ulipristal-based emergency contraception.

Patch and ring specifics - dosing, weight limits, missed-dose rules

Transdermal patch

Xulane/Zafemydeliver 35 mcg EE + 150 mcg norelgestromin daily. Twirladelivers 30 mcg EE + 120 mcg levonorgestrel daily. Apply to abdomen, buttock, upper torso, or upper arm; one patch weekly for 3 weeks, then a patch-free week. Efficacy drops in patients over roughly 90 kg for Xulane/Zafemy or BMI ≥30/weight >92 kg for Twirla, so this isn't a great option for higher body weight. Should not be used continuously.

Missed patchAction
Week 1, any delayApply now, backup x7 days, new Day 1 and patch-change day
Weeks 2–3, <48h lateRemove old, apply new, no backup, same patch-change day
Weeks 2–3, ≥48h lateRemove, apply new patch as a new cycle, backup x7 days
Week 4Remove when remembered, no backup, start next cycle on the usual day

Vaginal ring

NuvaRingreleases ~15 mcg EE + 120 mcg etonogestrel daily, lasts 3 weeks in, 1 week out, needs refrigeration before dispensing (stable at room temp for 4 months once out of the fridge). Can be removed up to 3 hours without needing backup. Annoverareleases 13 mcg EE + 150 mcg segesterone acetate, lasts a full year (13 cycles) on a 3-weeks-in/1-week-out schedule, doesn't need refrigeration, and hasn't been studied above BMI 29. No precise placement is needed for either ring, and both can stay in during sex, tampon use, and water-based topical antifungals or spermicides. Douching should be avoided.

Putting VTE risk in perspective

Baseline VTE risk in a healthy person of reproductive age is about 1–5 per 10,000 person-years.A combined oral contraceptive raises that to roughly 3–9 per 10,000.Pregnancy itself carries 5–20 per 10,000, and the postpartum period is 40–65 per 10,000, several times higher than the pill ever gets. Patients (and pharmacists in training) tend to catastrophize CHC clot risk while ignoring that pregnancy is the riskier state for clotting. Newer progestins (drospirenone, desogestrel, norgestimate) carry a modestly higher thrombosis risk than older ones like levonorgestrel, through mechanisms that aren't fully worked out, which matters when choosing among otherwise-similar options in a patient with borderline VTE risk factors.

Breast cancer risk, in numbers

The 2017 Danish cohort data behind the ACOG advisory put the excess breast cancer risk from CHC use at a number needed to harm (NNH) of about 1 in 7,690overall, and 1 in 50,000for those under 35. Compare that to the VTE NNH of about 1 in 729, VTE is the more clinically meaningful risk to counsel on, even though breast cancer is the one patients usually ask about first.

Managing breakthrough bleeding and first-cycle side effects

Nausea, breast tenderness, and breakthrough bleeding are common in the first cycle and typically resolve by the third. If breakthrough bleeding persists: first check adherence (missed pills are the most common cause), then ask about smoking. A patient who smokes needs cessation counseling or a method switch, not a dose change, since smoking itself destabilizes the endometrium. If adherence is good and the patient doesn't smoke, refer for evaluation of other causes, or consider increasing the EE dose slightly (to 30–35 mcg) and switching the progestin.

Drug interactions that reduce CHC/POP efficacy

ClassAgents
AntiepilepticsCarbamazepine, oxcarbazepine, phenytoin, topiramate, phenobarbital, primidone, felbamate
AntiretroviralsFosamprenavir (only when not ritonavir-boosted)
AntifungalGriseofulvin
AntibioticsRifampin and rifabutin
OtherLumacaftor/ivacaftor (cystic fibrosis), tirzepatide (delayed gastric emptying), St. John's wort
A common wrong answer

Most antibiotics do NOT interact with hormonal contraception.Rifampin and rifabutin are the real interaction; routine antibiotics like amoxicillin or azithromycin are not. Reflexively telling every patient on antibiotics to use backup contraception is outdated advice. The reverse interaction also exists and is easy to miss: CHCs can lower lamotrigine levelsand raise seizure risk, that one doesn't happen with progestin-only methods.

Progestin-Only Pills & DMPA

Progestin-only pills (the "minipill")

Best for patients who are lactating, estrogen-intolerant, or have an estrogen contraindication. Less effective than CHC and prone to irregular, unpredictable bleeding, and they carry more ectopic pregnancies than other hormonal methods. Must be taken at approximately the same time daily.

FormulationMissed-pill thresholdIf missed
Norethindrone 0.35 mg / Norgestrel 0.075 mg (OTC as Opill)>3 hours lateTake the missed pill, resume regular time, backup x48h
Drospirenone 4 mg (Slynd, 24 active + 4 placebo)>24 hours late(1 missed pill)1 pill late: resume as prescribed, no backup. ≥2 pills: take last dose + next dose, backup x7 days
The distractor to know cold

Not all progestin-only pills have the same missed-dose window.Norethindrone and norgestrel POPs have a strict 3-hour window because their progestin dose mainly acts on cervical mucus, an effect that fades fast. Slynd (drospirenone) behaves like a CHC with a 24-hour window because its dose reliably suppresses ovulation. If a question gives you "3 hours" as the missed-pill cutoff for a POP, it's not talking about Slynd.

Depot medroxyprogesterone acetate (DMPA)

FormulationDose / routeSite
Depo-Provera150 mg intramuscularGluteal or deltoid
Depo-SubQ Provera 104104 mg subcutaneous, prefilled syringe onlyAbdomen or anterior thigh
The BMD black box, correctly stated

DMPA carries a boxed warning for reduced bone mineral density, not for increased fracture risk, that distinction is tested. Loss is greater with longer duration and when started before age 20, but it's largely reversibleeven after more than 4 years of use. Guidance is not to continue beyond 2 yearsunless other methods are inadequate for that patient, and to ensure adequate calcium intake and weight-bearing exercise while on it. Do not routinely order a DXA scan just because someone is on DMPA.

Most common adverse effect by far is menstrual irregularity, worst in the first 6–12 months and improving after. Weight gain is typically modest (2–6 lb average). Weigh gain, mood change, and bone density concerns against DMPA's real advantages: no estrogen, minimal drug interactions, and a typical-use failure rate (4%) that's much better than the pill's.

LARCs - Implant & IUDs

Etonogestrel implant (Nexplanon)

A 4-cm radiopaque rod placed subdermally in the upper arm, releasing 60 mcg/day of etonogestrel initially, tapering to about 30 mcg/day by the end of use. Approved for 5 yearsas of a recent label update (previously 3). Efficacy exceeds 99% but may fall in patients over 130% of ideal body weight. Fertility returns within 30 days of removal; effects are quickly reversible. Watch for interactions with potent CYP450 inducers (rifampin, phenytoin, carbamazepine).

Intrauterine devices

ProductTypeDurationBleeding effect
ParaGardCopper, non-hormonal10 yearsHeavier menses, more cramping, especially first 3–6 months
Mirena, LilettaLevonorgestrel8 yearsLighter periods, up to 90% reduction in flow, many become amenorrheic
KyleenaLevonorgestrel, lower dose5 yearsLighter periods, more spotting than Mirena/Liletta
SkylaLevonorgestrel, lowest dose3 yearsLighter periods

All IUDs act mainly before implantation. Levonorgestrel IUDs add endometrial suppression and thickened mucus on top of the local foreign-body/inflammatory effect; copper works through direct spermicidal and ovicidal toxicity, no hormones at all. Both exceed 99% efficacy and reverse quickly on removal, with no long-term fertility impact and low PID risk despite the insertion procedure.

An outdated teaching to unlearn

Nulliparity and adolescence are not reasons to avoid an IUD or implant.Given their high efficacy and low complication rates, LARCs are appropriate first-line options in both populations. The old "IUDs are only for women who've had children" teaching is wrong and costs patients access to the most effective reversible methods.

PAINS - when an IUD patient needs to be seen

Period late, abnormal bleeding · Abdominal pain or pain with intercourse · Infection exposure/STI, abnormal discharge · Not feeling well, fever, chills · String missing, shorter, or longer than expected. Any of these warrants an exam to check for expulsion, perforation, pregnancy (including ectopic), or infection.

Representative Product & Dosing Table

Dozens of brand names exist for a handful of formulations. Know the representative dose combinations and the method-level doses below, not every brand name.

Method / Example brandCompositionRegimen
Monophasic COC (representative low-dose)
e.g. Aviane, Lutera (Levonorgestrel/EE)EE 20 mcg + levonorgestrel 0.1 mg21 active + 7 placebo
e.g. Yasmin, Ocella (Drospirenone/EE)EE 30 mcg + drospirenone 3 mg21 active + 7 placebo, monitor K⁺
NextstellisEstetrol 14.2 mg + drospirenone 3 mg24 active + 4 placebo
Lo Loestrin FeEE 10 mcg + norethindrone acetate 1 mg26 active (ultra-low estrogen) + 2 placebo; adherence critical
Multiphasic COC (representative)
Ortho Tri-Cyclen and genericsEE 35 mcg + norgestimate 0.18/0.215/0.25 mg stepped21 active (triphasic) + 7 placebo
NataziaEstradiol valerate + dienogest, four-phasic26 active + 2 placebo
Extended cycle
Seasonique and similarEE 30 mcg + levonorgestrel 0.15 mg84 active + 7 low-dose EE (4 cycles/year)
Progestin-only pill
Norethindrone (Camila, Micronor, generics)Norethindrone 0.35 mg28 active, no placebo, 3h window
SlyndDrospirenone 4 mg24 active + 4 placebo, 24h window
Transdermal / vaginal
Xulane / Zafemy patchEE 35 mcg + norelgestromin 150 mcg/day1 patch weekly x3, then patch-free week
Twirla patchEE 30 mcg + levonorgestrel 120 mcg/daySame schedule; BMI <30 for full efficacy
NuvaRingEE 15 mcg + etonogestrel 120 mcg/day3 weeks in, 1 week out
AnnoveraEE 13 mcg + segesterone acetate 150 mcg/day3 weeks in, 1 week out, reusable x1 year
Injectable / implant
Depo-ProveraMedroxyprogesterone 150 mg IMEvery 12 weeks
Depo-SubQ Provera 104Medroxyprogesterone 104 mg SubQEvery 12 weeks
NexplanonEtonogestrel 68 mg rodEvery 5 years
Emergency contraception
Levonorgestrel (Plan B and generics, OTC)1.5 mg single doseWithin 72h (up to 120h), less effective >75 kg
Ulipristal acetate (Ella, Rx)30 mg single doseWithin 120h, more weight-tolerant than LNG

Special Populations

PopulationGuidance
Age >35, nonsmokerCHC with <50 mcg EE is reasonable if healthy. No demonstrated increased CV risk with low-dose CHC in healthy, nonobese patients.
Age >35, smoker ≥15 cig/dayCHC contraindicated. Use progestin-only.
Smoker <35If using CHC, favor <50 mcg EE to reduce MI risk.
HypertensionCHC acceptable if <35 and well-controlled/monitored. Avoid CHC at 140–159/90–99. Contraindicated at ≥160/100. CHC itself can raise BP 6–8 mmHg regardless of dose.
DiabetesCHC safe if <35, nonsmoking, no vascular disease. Avoid CHC with >20 years duration or vascular complications.
ObesityCOC efficacy drops with obesity, especially low-dose formulations. IUD, implant, and DMPA remain highly effective. VTE risk is also elevated with obesity, favor progestin-only after 35.
Migraine without auraCHC reasonable if <35, nonsmoking, and monitored; can go either direction on frequency.
Migraine with auraCHC contraindicated at any age due to stroke risk. Switch to progestin-only if aura develops on CHC.
Breast cancer, current or pastCHC contraindicated. BRCA1/2 carriers without active cancer: use is controversial, individualize.
SLE with antiphospholipid antibodiesAvoid CHC and progestin-only products; copper IUD is often the best option.
Postpartum, breastfeedingAvoid estrogen <21 days (VTE risk); avoid through 42 days if breastfeeding with other VTE risk factors. Progestin-only methods are fine sooner.
Postpartum, non-breastfeedingCHC still category 4 (contraindicated) <21 days, category 2–3 21–42 days depending on VTE risk factors.
Seizure disorder on enzyme-inducing AEDsCHC and POP efficacy reduced (phenytoin, carbamazepine, barbiturates, topiramate, oxcarbazepine). Favor IUD, implant, or DMPA instead.
Oregon pharmacist prescribing (HB2879/2527) - what P3s here actually need to know

Oregon law lets a pharmacist prescribe and administer injectable hormonal contraception and prescribe/dispense self-administered hormonal contraceptives, for patients ≥18 (or under 18 with evidence of a prior prescription for the method).

Required of the pharmacist:complete Board of Pharmacy-approved training, provide a self-screening questionnaire, refer to a women's health provider when appropriate, and give the patient a record of the prescription. Records and training documentation must be retained (training 6 years, visit records 7 years minimum), and the visit must follow the PPCP with a face-to-face physical assessment (BP).

Prohibited:requiring an appointment, prescribing to someone without evidence of a clinical visit within the past 3 years, and prescribing to yourself or family members. Insurance covers the medication; the visit itself is typically billed as a separate service fee.

The workflow mirrors the PPCP: Collect(insurance, questionnaire, meds, BP) → Assess(pregnancy status, contraindications against US MEC) → Plan(patient preference, options, refer if indicated) → Implement(counsel, provide record, notify PCP) → Follow-Up(3 months for new starts, sooner for side effects, refer as needed).

In the original Direct Access pilot study behind this law, of 214 patients screened by community pharmacists: 8.8% were referred out for contraindications, and among those started, 97.7% were satisfied and 97.1% said they'd refer a friend. The self-screening questionnaire performed well enough that patients could reliably assess their own risk factors compared to a provider doing it, which is the evidence base the whole statewide protocol rests on.

Emergency Contraception

Used after unprotected or inadequately protected intercourse: no method used, condom failure, or a missed pill/late injection/expelled ring or patch. It is not a routine ongoing contraceptive method, it's a backstop.

OptionDose / accessWindowKey limiting factor
Copper IUDPlaced by providerMost effective option; can be placed and left as ongoing contraceptionNone, effective regardless of weight
Ulipristal acetate (Ella)30 mg single dose, prescription onlyUp to 120h (5 days)Efficacy declines >88 kg / BMI 35. Won't work if a progestin-containing method is used within 5 days before or after.
Levonorgestrel (Plan B, generics)1.5 mg single dose, OTCLabeled 72h, effective to ~120h with declining efficacyEfficacy approaches placebo at >70–75 kg or BMI ≥26
Yuzpe methodHigher-dose combined pillsHistorical, rarely used nowMore nausea/vomiting than dedicated EC products
The efficacy-by-weight pearl

Body weight is the single strongest predictor of EC failure.Obese patients have roughly 3x the pregnancy risk on levonorgestrel EC compared to normal weight. Ulipristal holds up better at higher weights but also declines past 88 kg/BMI 35. The copper IUD is the only EC option unaffected by weight, so it's the first offer for a higher-weight patient at real risk, if they're willing.

Choosing between UPA and LNG plus starting ongoing contraception the same day

If a copper IUD is declined: use UPA + delayed startof a progestin-containing method (wait 5 days) for a patient at higher pregnancy risk, higher weight, or likely to return for follow-up. Use LNG + immediate startof ongoing contraception for lower-risk patients unlikely to return or wait. Starting a progestin method right after UPA blunts UPA's efficacy, this is a real interaction, not a theoretical one.

EC myths to correct out loud

EC does not cause birth defects. EC does not cause an abortion(it works before or around ovulation/fertilization, not after implantation). EC can be purchased in advance of need.A Florida pharmacist survey found 56%, 46%, and 78% of pharmacists respectively believed the opposite of each of these, all false. Correct these proactively, patients pick up on hesitation.

In Oregon,pharmacists can prescribe both LNG and UPA emergency contraception, and OHP covers LNG EC without a prescription requirement. Counsel on antiemetic pretreatment (about 1 hour before the dose) if nausea is a concern, expected menstrual changes including a delayed next period, and to test for pregnancy and follow up if menses hasn't returned within 3 weeks. EC offers no STI protection, use the visit to screen for STI risk and discuss ongoing contraception.

⏹ Medication Pregnancy Termination

For early pregnancy termination (≤70 days gestation), the FDA-approved regimen is mifepristone 200 mg orally on day 1, then misoprostol 800 mcg buccally 24–48 hours later.Combined, this regimen is about 98% effective through 49 days.

Boxed warning

Mifepristone carries a boxed warning for infection and excessive bleeding.Heavy bleeding can signal an incomplete termination or another complication and needs prompt medical attention, this is not a "wait and see" adverse effect.

Monitoring - What, When, Why

MethodWhenWatching for
Blood pressure (all CHC users)Baseline, then annuallyRising BP that would push the patient into a higher MEC category
Glucose (diabetes/glucose intolerance)When CHC is started or stoppedGlycemic shifts from estrogen/progestin effects
Potassium (drospirenone products)Regularly if on ACEi, ARB, K-sparing diuretic, or aldosterone antagonistHyperkalemia (drospirenone has mild antimineralocorticoid activity)
NexplanonAnnuallyMenstrual disturbance, weight change, site inflammation/infection, acne, breast tenderness, headache, hair loss
DMPAEvery 3 months (at reinjection)Weight gain, menstrual disturbance, mood changes; BMD concern with >2 years of use
IUD (any type)1–3 month intervals after placementProper positioning, string check, menstrual pattern changes, upper genital tract infection
All hormonal contraceptionAnnual visitCytologic screening if due, pelvic/breast exam if indicated, breakthrough bleeding, amenorrhea, weight gain, acne. None of these need to happen before the first prescription.
All patientsOngoingSTI/HIV risk screening and condom counseling, since most methods here don't cover STIs

Patient Counseling - What You'll Actually Say

  • Setting expectations on a new pill/patch/ring:"The first two or three cycles can bring some nausea, breast tenderness, or spotting between periods. That almost always settles down by the third pack. Keep taking it unless you get one of the ACHES symptoms."
  • Explaining ACHES:"If you get bad abdominal pain, chest pain or trouble breathing, a severe headache with weakness or numbness, vision changes, or severe leg pain or swelling, stop the medication and get seen right away. Those are rare, but they're the ones we don't wait on."
  • Missed-pill routine:"Pick a time you'll actually be doing something else every day, brushing your teeth, an alarm, whatever sticks, and take it then. If you miss one, here's exactly what to do (walk through the specific product's rule), and use a backup method for the days it tells you to."
  • Myth-busting, said plainly:"This won't make you infertile, it won't cause the hormones to 'build up' and require a break, and it's not going to reliably make you gain a lot of weight. DMPA is the one method that can delay your fertility coming back, by around 10 months on average, everything else reverses fast."
  • DMPA counseling:"Your period may get irregular for the first several months and that's expected, not a sign it's failing. Come back for your next shot within about 12 weeks, if it's more than a week or two late we'll check a pregnancy test first. Make sure you're getting enough calcium and staying active while you're on this."
  • IUD counseling (PAINS):"Call if your period is very late, you have new pelvic pain or pain with sex, signs of infection or unusual discharge, fever or feeling unwell, or if the strings feel missing, shorter, or longer than before."
  • No STI protection reminder:"This protects against pregnancy, not infections. If that's a concern, condoms are still the move, and they work fine alongside your other method."
  • Emergency contraception:"Take it as soon as possible, it works better the sooner you take it. You might feel nauseated, an anti-nausea medicine an hour before can help. Your next period might come early or late, if it doesn't show up within three weeks, take a pregnancy test."
  • Antibiotic question:"Most antibiotics don't actually interact with your birth control, rifampin is the one that really does. If you're prescribed that one, we'll talk about backup protection."

High-Yield Recall Sheet

  • Efficacy tiers:LARC <1% typical use, other hormonal 3–7%, barrier 13–28%, fertility awareness worst of the reversible options.
  • Estrogen suppresses FSH/LH surge; progestin thickens mucus, atrophies endometrium, and (dose-dependent) blocks ovulation.
  • POP missed-dose windows differ:norethindrone/norgestrel = 3 hours; drospirenone (Slynd) = 24 hours.
  • DMPA:150 mg IM or 104 mg SubQ, every 12 weeks, BMD black box (not fracture, reversible), stop by 2 years unless nothing else works.
  • Nexplanon now lasts 5 years(updated from 3), releases 60 mcg/day tapering to 30 mcg/day.
  • IUD durations:ParaGard 10y, Mirena/Liletta 8y, Kyleena 5y, Skyla 3y.
  • ACHES= abdominal pain, chest pain, headache, eye problems, severe leg pain → stop CHC immediately.
  • PAINS= period late, abdominal pain, infection signs, not feeling well, string change → IUD needs evaluation.
  • CHC category-4 conditions:smoking ≥15/day and age ≥35, migraine with aura (any age), BP ≥160/100, current/recent VTE, current breast cancer, <21 days postpartum.
  • Progestin-only methods dodge nearly all estrogen-related MEC restrictions, that's the go-to swap when CHC is contraindicated.
  • VTE risk in context:baseline 1–5/10,000, COC 3–9/10,000, pregnancy 5–20/10,000, postpartum 40–65/10,000.
  • Rifampin/rifabutin reduce CHC efficacy; most other antibiotics do not.Enzyme-inducing anticonvulsants do too.
  • CHC lowers lamotrigine levels, the reverse-direction interaction that's easy to forget.
  • No exam or Pap required before prescribing CHC, just history and blood pressure.
  • LNG EC loses efficacy above ~75 kg/BMI 26; UPA holds up better but fades past 88 kg/BMI 35; copper IUD is weight-independentand the most effective EC option overall.
  • UPA + a progestin method within 5 days cancels UPA's effect, sequence matters.
  • EC does not cause abortion or birth defects, and it can be bought in advance.
  • Mifepristone + misoprostolfor termination ≤70 days: mifepristone 200 mg PO day 1, misoprostol 800 mcg buccal 24–48h later, ~98% effective. Misoprostol is never given orally.
  • Nulliparity and adolescence are not contraindications to LARC, they're appropriate first-line candidates.
  • Oregon pharmacists can prescribe self-administered hormonal contraception and administer DMPAunder HB2879/2527, with mandatory training, screening tool use, and record retention.