Contraception

Overview & Definition

Contraception is the intentional prevention of pregnancy following unprotected sexual intercourse (UPSI). Method choice balances efficacy, safety, side-effect profile, reversibility, coital independence, acceptability, cost and the woman's medical, obstetric and sexual history. The guiding clinical principle in UK and international guidance is to offer long-acting reversible contraception (LARC) first — copper-bearing intrauterine device (Cu-IUD), levonorgestrel-releasing intrauterine system (LNG-IUS), the subdermal etonogestrel implant, and depot medroxyprogesterone acetate — because these methods are user-independent and have the lowest typical-use failure rates.^[1][2]

Efficacy is expressed as the perfect-use failure rate (correct and consistent use) and the typical-use failure rate (allowing for missed pills, late re-attendance, displacement and human error). For LARC the two figures are nearly identical; for user-dependent methods such as the combined pill, patch, ring, condom and fertility awareness, the typical-use failure rate is many times higher than the perfect-use rate, which is why unintended pregnancy concentrates among pill and condom users. Trussell's analysis of US data placed typical first-year failure of the pill at about 9 percent and the condom at 18 percent, against under 1 percent for LARC.^[4]

The UK Medical Eligibility Criteria (UKMEC) are applied at every consultation. UKMEC is a four-category scale that grades the safety of each method in the presence of a given medical condition, allowing clinicians to choose safely without withholding effective contraception unnecessarily.^[1]

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Classification

Contraceptive methods are most usefully grouped by efficacy tier and duration of action. LARC methods deliver contraception for months to years without user action and share typical-use failure under 1 percent. Short-acting hormonal methods (combined pill, patch, ring, progestogen-only pill) require daily, weekly or monthly adherence. Barrier methods are coitally dependent and also protect against sexually transmitted infection (STI). Natural methods rely on avoiding or timing intercourse. Sterilisation is permanent. Emergency contraception is a back-up after method failure or UPSI.

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Epidemiology & Risk Factors

In the UK the combined oral contraceptive pill and the male condom remain the most commonly used reversible methods, each chosen by about a quarter of contraceptive users, while LARC uptake has risen steadily with the publication of effectiveness data and NICE guidance to about 12 to 15 percent of women of reproductive age. Sterilisation accounts for around 7 percent. Uptake patterns mirror availability, clinician confidence, and reimbursement; countries with state-funded LARC programmes show the steepest fall in unintended teenage pregnancy.^[1][2]

Unintended pregnancy affects 30 to 50 percent of all pregnancies globally. The risk is concentrated in women under 25, those on lower incomes, late presenters for postnatal contraception, and — most importantly — users of user-dependent methods who experience method failure or discontinuation. The Contraceptive CHOICE project in the United States demonstrated that when counselling removes cost and access barriers and offers LARC first, three-quarters of women choose a LARC method and unintended pregnancy and abortion rates fall dramatically.^[2]

Risk factors for contraceptive failure include inconsistent or incorrect use, enzyme-inducing drug co-prescription, late restart after the pill-free interval, vomiting or severe diarrhoea within 3 hours of pill-taking, BMI over 35 for some oral emergency methods, and device expulsion or perforation. Risk factors for serious contraceptive harm — chiefly arterial or venous thrombosis on combined hormonal contraception — are summarised by the UKMEC framework and include age, smoking, hypertension, migraine with aura, prior VTE, thrombophilia, obesity, and immobility.^[1][5]

Pathophysiology

Contraception interrupts the reproductive cascade at one or more of four points: ovulation, gamete transport, fertilisation, or implantation. Understanding the mechanism explains each method's efficacy, side-effect profile, and eligibility.

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Combined hormonal contraception (CHC) — the combined oral contraceptive pill, the transdermal patch, and the vaginal ring — combines a synthetic oestrogen with a progestogen. Its safety profile, and therefore its eligibility, is driven by both components. In the Danish national registry cohort of over 8 million woman-years, the relative risk of confirmed venous thromboembolism versus non-users was 2.9 (95 percent CI 2.2 to 3.8) for pills containing 30 to 40 micrograms of ethinylestradiol with levonorgestrel, but 6.2 with gestodene, 6.4 with drospirenone and 6.6 with desogestrel — while progestogen-only pills and levonorgestrel-releasing intrauterine devices showed no increase in risk. Arterial risk also tracks the oestrogen dose: among CHC users, ethinylestradiol doses of 30 micrograms or more carried higher ischaemic stroke odds than doses under 30 micrograms (OR 1.52, 95 percent CI 1.02 to 2.26), and a personal migraine history doubled stroke odds (OR 2.00).^[5][8]

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Progestogen-only methods — the progestogen-only pill, the etonogestrel implant, depot medroxyprogesterone acetate, and the levonorgestrel intrauterine system — differ mainly in how completely they suppress ovulation. In a 12-month randomised double-blind comparison of two progestogen-only pills, desogestrel 75 micrograms daily inhibited ovulation significantly more than levonorgestrel 30 micrograms daily (P under 0.001). The etonogestrel implant inhibits ovulation within one day of insertion and remains effective for three years. DMPA produces a prolonged hypo-oestrogenic state, which is the basis of its documented skeletal effects. The Danish cohort found no increase in venous thromboembolism risk with progestogen-only pills or levonorgestrel-releasing intrauterine devices, which is why they are the alternatives when oestrogen-containing methods are contraindicated.^{[5][7][9][10]}

The copper-bearing IUD is the only long-acting, non-hormonal, locally acting method. Copper ions release into the uterine and tubal fluid, creating a sterile inflammatory reaction in the endometrium that is toxic to ova and sperm and prevents fertilisation; copper also inhibits sperm motility and capacitation. When inserted after ovulation the device prevents implantation. This is why the Cu-IUD is the most effective emergency contraception and why it tends to increase menstrual blood loss and dysmenorrhoea. The LNG-IUS instead produces a thin, inactive endometrium and viscous cervical mucus, which is why it dramatically reduces menstrual loss and is licensed for heavy menstrual bleeding.^[1]

Sterilisation interrupts anatomical gamete transport — occluding or dividing the fallopian tubes in women and the vas deferens in men — and is intended to be permanent. Natural methods identify or avoid the fertile window. Lactational amenorrhoea relies on the hyperprolactinaemia of exclusive breastfeeding suppressing gonadotropin-releasing hormone pulsatility, which prevents ovulation for up to 6 months postpartum.

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Clinical Presentation

The "presentation" in contraception is rarely a symptom; it is a request — for contraception, for emergency contraception, for a method change, or for a complication review. A purposeful consultation captures the relevant history and applies UKMEC.

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At initiation the focused history covers menstrual pattern and cycle, obstetric history (parity, mode of delivery, complications), lactation, sexual history (frequency, partner(s), STI risk, prior UPSI in the current cycle), medical history (venous or arterial thromboembolism, thrombophilia, cardiovascular disease, migraine — distinguishing with and without aura — hypertension, diabetes with vascular disease, liver disease, breast cancer, SLE, post-transplant status), medications (especially enzyme inducers: rifampicin, rifabutin, antiepileptics — carbamazepine, phenytoin, phenobarbital, primidone, oxcarbazepine, topiramate — St John's wort, certain antiretrovirals), smoking, alcohol, weight/BMI, and plans for future fertility. A focused examination measures blood pressure, BMI, and (where indicated) breast and pelvic examination. A cervical screening test is performed only if due.^[1]

At follow-up or unscheduled review the key symptoms and their causes are:

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• Unscheduled or irregular bleeding on POP, implant, DMPA, or LNG-IUS — common in the first 3 to 6 months; investigate if heavy, persistent, or new after a stable interval, by excluding infection (chlamydia, gonorrhoea), pregnancy, gynaecological pathology (cervical, endometrial), and device issues (expulsion, perforation).
• Amenorrhoea — pregnancy first; then expected on DMPA (over 50 percent by 12 months) and LNG-IUS (20 to 80 percent depending on device and year).
• Chest pain, dyspnoea, calf pain or swelling, sudden severe headache, visual disturbance, focal neurology, or jaundice on CHC — treat as VTE, PE, ischaemic stroke, or hepatic complication until proven otherwise.
• Severe lower abdominal pain in an IUD/IUS user — perforation, pelvic infection, pregnancy (intrauterine or ectopic), or expulsion.
• Missing threads on IUD/IUS review — expulsion, perforation, or simply retracted; locate by ultrasound.
• Acne, weight change, mood change, breast tenderness, headache — common androgenic or hormonal side effects; usually settle within 3 months but drive discontinuation if persistent.

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Differential Diagnosis

The most frequent diagnostic problem is unscheduled bleeding or amenorrhoea in a contraceptive user. The differential is approached systematically; the contraceptive method is a diagnosis of exclusion, made only after the dangerous and treatable causes are excluded.

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A 28-year-old on the implant reports 3 weeks of unscheduled bleeding and left-sided pelvic pain. What is the first investigation?ShowHide

Exclude pregnancy and ectopic with a urinary or serum β-hCG — do not attribute bleeding to the implant until pregnancy is excluded. Then screen for chlamydia and gonorrhoea and arrange a pelvic ultrasound to confirm implant position and adnexal anatomy.

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Clinical & Bedside Assessment

The bedside assessment in contraception is brief and protocol-driven. The aim is to identify UKMEC 3 and 4 conditions and to recognise complications.

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History — as detailed above. Quantify smoking in cigarettes per day (the 35-year and 15-cigarette thresholds matter for UKMEC). Establish migraine phenotype by asking specifically about aura — focal neurological symptoms (visual, sensory, motor, speech) developing over 5 minutes and lasting under 60 minutes before headache; aura makes CHC UKMEC 4. Document any personal or strong family history (first-degree relative under 45) of VTE. Establish the postpartum day and breastfeeding status. List all medications including over-the-counter St John's wort.^[1][8]

Examination — blood pressure, weight, height and BMI. Breast examination in women with breast symptoms or over 35 with family history. Speculum and bimanual pelvic examination if STI screen, cervical screening, or device check is needed. Auscultation of the heart and lungs if cardiovascular symptoms. Examine the calves for swelling and tenderness if VTE is suspected. For the implant, palpate the insertion site and document the position.

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Named signs relevant to complications:

• Homans' sign (calf pain on dorsiflexion) — historical and unreliable for DVT; diagnosis is by D-dimer and Doppler ultrasound.
• Lost threads at IUD/IUS review — locate device by ultrasound; consider perforation or expulsion.
• Visible thread length change — possible device displacement.

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Investigations

Routine investigations before starting contraception are minimal. The principle is targeted testing driven by history and UKMEC.

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Management — Resuscitation

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Contraceptive emergencies are rare but time-critical. The key syndromes are combined-hormonal-contraception-related thromboembolism or stroke, uterine perforation or pelvic infection with an IUD/IUS, and septic miscarriage with an IUD in situ.

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Management — Definitive & Stepwise

The definitive management is method selection guided by efficacy, UKMEC, and patient preference, with LARC offered first. NICE Clinical Guideline 30 (long-acting reversible contraception) directs clinicians to actively offer LARC to reduce unintended pregnancy, and the FSRH provides detailed eligibility and initiation guidance that the UKMEC paper summarises.^[1][2]

Combined oral contraceptive (COC) pill

The COC combines ethinylestradiol, typically 30 to 40 micrograms in the pills studied in the Danish national cohort, with a progestogen — commonly levonorgestrel or norethisterone, or the newer desogestrel, gestodene or drospirenone. Choice of formulation is driven by thrombotic risk: relative to non-users, the confirmed venous thromboembolism risk is about 2.9 with levonorgestrel pills but 6.2 to 6.6 with gestodene, drospirenone or desogestrel, and 2000 women would need to shift from a higher-risk pill to levonorgestrel to avert one event. Oestrogen dose also matters for arterial events — among CHC users, 30 micrograms or more of ethinylestradiol carried higher ischaemic stroke odds than under 30 micrograms (OR 1.52), and any migraine history doubled stroke odds (OR 2.00), which is why combined hormonal contraception is restricted in migraine with aura. Progestogen-only pills and the levonorgestrel intrauterine system did not increase venous thromboembolism risk in the same cohort.^[5][8]

Progestogen-only pill (POP)

The two clinical types differ in dose and in ovulation suppression. In a 12-month randomised double-blind comparison, desogestrel 75 micrograms produced significantly greater inhibition of ovulation than levonorgestrel 30 micrograms (P under 0.001). The key advantage over combined methods: the Danish cohort found no increase in venous thromboembolism risk with progestogen-only pills or levonorgestrel-releasing intrauterine devices, making them options when oestrogen is contraindicated, including in women with thrombotic risk factors. Adherence is the principal limitation — as with every user-dependent method, typical-use failure exceeds perfect-use failure.^[5][10][4]

Injectable: depot medroxyprogesterone acetate (DMPA)

DMPA 150 mg intramuscularly every 3 months is the recommended regimen, with contraceptive efficacy exceeding 99 percent. In the Contraceptive CHOICE cohort, unintended-pregnancy rates among DMPA users were similarly low to those of IUD and implant users, regardless of age. Disadvantages: return of fertility is delayed relative to other methods — a follow-up study of women stopping contraception for a planned pregnancy found a median delay to conception of 5.5 months plus the duration of effect of the last injection (about 15 weeks), i.e. around 9 months after the last injection, versus 4.5 months after IUD removal; and DMPA induces a prolonged hypo-oestrogenic state, with a large UK case-control study showing increased fracture risk that rises with longer exposure (adjusted OR 2.41 for 3 to 9 prescriptions).^{[2][7][13][14]}

Subdermal implant (Nexplanon)

A single 68 mg etonogestrel rod inserted subdermally in the inner upper arm. It inhibits ovulation within one day of insertion and provides effective contraception for 3 years, with fertility returning within one month of removal. Insertion and removal by trained medical professionals are simple, and only minor complications have been documented. Adverse effects are mild — abnormal bleeding is the principal one, followed by weight gain, acne, breast pain and headache, and bleeding disturbance is the main reason for discontinuation. In the CHOICE cohort, implant users shared the low LARC failure rate of 0.27 per 100 participant-years.^[2][9]

Intrauterine contraception

Copper-bearing IUD (Cu-IUD) — a T-shaped plastic frame wound with copper wire; licensed for 5 or 10 years depending on device (380 mm² surface area devices last 10 years). Non-hormonal; immediate return to fertility on removal; the most effective emergency contraception. Side effects: heavier, longer, more painful periods (most pronounced in the first 3 to 6 months), small risk of perforation (about 1 in 1000 insertions), expulsion (3 to 5 percent, highest in first 3 months and within 3 months of delivery), and pelvic infection (highest in first 3 weeks after insertion).^[1][2]

Levonorgestrel-releasing intrauterine system (LNG-IUS) — the 52 mg system (Mirena). It was initially approved for 5 years; the Mirena Extension Trial showed that it maintains high contraceptive efficacy, user satisfaction and a favourable safety profile through 8 years of use, with about half of continuing women experiencing amenorrhoea or infrequent bleeding during years 5 to 8. Return of fertility after discontinuation is prompt — 77.4 percent of women who stopped for pregnancy conceived within 12 months. Danish registry data found no increase in venous thromboembolism risk with levonorgestrel-releasing intrauterine devices, unlike combined pills.^[5][11]

Barrier methods

The male latex condom is the only method (with the female condom) that protects against STI including HIV, and dual protection (condom plus hormonal or intrauterine method) is advised for all women at STI risk. Use a new condom for each act, withdraw while still erect, and avoid oil-based lubricants with latex (degradation). The female condom (FC2) is polyurethane or nitrile and can be inserted before intercourse. The diaphragm (with spermicide, ideally a cervical cap) must be fitted and left in place for at least 6 hours after intercourse. Spermicides (nonoxynol-9) used alone have high failure and may increase HIV transmission with frequent use.^[1]

Natural methods

Fertility awareness-based methods identify the fertile window (around ovulation, with sperm survival up to 5 days and ovum survival 12 to 24 hours) using calendar, basal body temperature, cervical mucus, or combined (symptothermal) indicators; typical-use failure 12 to 24 percent and demands motivation and training. Lactational amenorrhoea method (LAM) is 98 percent effective when all three criteria are met: exclusive breastfeeding on demand day and night, the baby is under 6 months old, and the woman remains amenorrhoeic. Withdrawal has a typical-use failure around 22 percent. These methods protect against STI not at all.^[1]

Sterilisation

Female sterilisation — laparoscopic tubal occlusion with clips, rings, or diaphragms, or salpingectomy (which also reduces ovarian cancer risk); hysteroscopic tubal cannulation/implants (Essure) have been withdrawn from the market in many countries. Failure rate about 1 in 200; regret is commoner in women under 30 and around the time of a pregnancy. If sterilisation fails the pregnancy is more likely to be ectopic. Vasectomy — day-case local anaesthetic procedure to divide or occlude the vas deferens; the most effective method of contraception but not immediately effective. Two consecutive semen analyses must show azoospermia (or rare non-motile sperm under 100 000 per mL), typically after 20 ejaculations and 12 weeks, before the man can rely on the procedure; alternative contraception is essential in the interim.^[1]

Emergency contraception

Emergency contraception is offered after UPSI, method failure, or sexual assault. In a randomised non-inferiority trial of women requesting emergency contraception within 5 days of unprotected intercourse, a copper T380A IUD prevented all pregnancies (0 of 321 women, 95 percent CI 0 to 1.1) — and a levonorgestrel 52 mg IUD was non-inferior (1 of 317, 0.3 percent). For oral therapy, a randomised trial and meta-analysis compared ulipristal acetate 30 mg with levonorgestrel 1.5 mg, each as a single supervised oral dose, and found ulipristal the more effective of the two. A Cochrane review of 115 trials (60,479 women) confirmed the hierarchy among oral regimens: levonorgestrel caused fewer pregnancies than the Yuzpe regimen (RR 0.57), and mid-dose mifepristone (25 to 50 mg) was more effective than levonorgestrel.^[3][6][12]

Stepwise Management

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Missed-pill rules

The Faculty of Sexual and Reproductive Healthcare simplified the missed-pill rules. For a combined pill: a pill taken more than 24 hours late counts as missed. One missed pill — take it as soon as remembered, continue the pack, no additional precautions. Two or more missed pills (over 48 hours late) — take the most recent missed pill, continue the pack daily, use condoms or abstain for 7 days, and use emergency contraception if unprotected sex occurred in the pill-free interval or the first 7 days of the current pack, or if more than seven pills were missed. For the progestogen-only pill: a traditional POP taken more than 3 hours late (over 12 hours late for desogestrel) is missed — take it as soon as remembered, continue daily, and use additional precautions for 2 days (48 hours).^[1]

Specific Subtypes & Scenarios

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Perimenopause and menopause — contraception is needed until menopause is confirmed, and the 52 mg LNG-IUS maintained contraceptive efficacy through 8 years in its extension trial, covering much of the perimenopausal window. Adolescents — LARC is first-line: LARC effectiveness is not altered in adolescents and young women, whereas women under 21 using pills, patch or ring had almost twice the unintended-pregnancy risk of older users. Women with obesity — eligibility is graded method by method in the UKMEC/WHO MEC, and the copper IUD avoids systemic steroid exposure. Women with cardiac disease or disability — apply the MEC categories and, where capacity is impaired, a formal best-interests assessment; the copper IUD is often the safest hormone-free option.^[2][11][16]

Complications & Pitfalls

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Classic pitfalls — prescribing CHC to a woman with migraine with aura (UKMEC 4); relying on the COC pill-free interval when enzyme-inducing drugs are co-prescribed; missing the diagnosis of ectopic pregnancy in an IUD user with abdominal pain; failing to confirm azoospermia before clearing a vasectomy patient; under-dosing levonorgestrel emergency contraception in women over 70 kg or on enzyme inducers; and forgetting that the LNG-IUS for HRT endometrial protection expires at 5 years even though it lasts 8 years for contraception.^[1]

Prognosis & Disposition

Contraception is highly effective when used correctly and consistently; the population burden of unintended pregnancy falls with LARC access. LARC methods achieve typical-use failure under 1 percent, while user-dependent methods (pill, condom, fertility awareness) carry typical-use failure of 9 to 24 percent. Fertility returns immediately after stopping the pill, patch, ring, POP, implant, Cu-IUD, or LNG-IUS, and after vasectomy once azoospermia is confirmed; DMPA delays return of fertility by a median of 9 to 10 months from the last injection.^[1][2]

Disposition: initiation and most follow-up are outpatient; IUD/IUS insertion is a day-case clinic procedure. Same-day emergency contraception is offered in primary care, sexual health clinics, and pharmacies. The emergency department is reserved for complications — suspected VTE/PE, stroke, perforation, ectopic, or sepsis. The safety-net is explicit counselling of red-flag symptoms (chest pain, dyspnoea, calf pain, severe headache, visual change, severe abdominal pain) and a 24-hour contact for unscheduled bleeding, lost threads, or pregnancy concerns.

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Special Populations

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Evidence, Guidelines & Regional Differences

The UK Medical Eligibility Criteria (UKMEC), adapted from the WHO Medical Eligibility Criteria, is the UK standard and is summarised in the FSRH guidance; the 2016 update refined categories for breastfeeding, diabetes, and HIV, among others.^[1] NICE Clinical Guideline 30 (Long-acting reversible contraception) directs clinicians to increase LARC uptake to reduce unintended pregnancy. The WHO Medical Eligibility Criteria (5th edition, 2015) is the international standard with broadly congruent categories.

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Landmark evidence — Winner and colleagues (NEJM 2012, the Contraceptive CHOICE project) showed that LARC methods had failure rates 10 to 20 times lower than the pill, patch, or ring, with continuation highest for the IUD and implant.^[2] Lidegaard and colleagues (BMJ 2011) quantified the VTE risk of combined pills, showing that third- and fourth-generation progestogens and higher oestrogen doses carry the highest risk, informing the preferential prescribing of levonorgestrel- or norethisterone-containing pills.^[5] Glasier and colleagues (Lancet 2010) demonstrated that ulipristal is non-inferior and overall superior to levonorgestrel for emergency contraception, and the Cochrane review (Shen 2019) confirmed this hierarchy with the Cu-IUD most effective of all.^[3][6] Kyvernitakis and colleagues (Osteoporosis International 2017) reported a UK signal of increased fracture risk with DMPA, informing counselling on long-term use.^[7]

Controversies — the absolute VTE risk on CHC remains low (around 9 to 10 per 10 000 woman-years, against 2 to 3 per 10 000 in non-users), and the contraceptive benefit usually outweighs it; the choice of progestogen is a risk modifier. The bone-density effect of DMPA is largely reversible and must be balanced against the substantial contraceptive and non-contraceptive benefits. The role of LNG-IUS for HRT endometrial protection beyond 5 years is an area of active review.

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Exam Pearls

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• Migraine with aura = absolute contraindication to CHC (UKMEC 4) — the single most tested UKMEC fact. Stroke risk is amplified by oestrogen dose.^[8]
• Smoking, age over 35 and hypertension raise combined-method thrombotic risk — graded condition by condition in the UKMEC/WHO MEC tables.^[16]
• DMPA 150 mg intramuscularly every 3 months delays fertility return by a median of around 9 months and carries a fracture signal that rises with longer exposure.^[7][13][14]
• Copper IUD is the most effective emergency contraception — 0 pregnancies in 321 women in a randomised trial — and the only non-hormonal LARC.^[12]
• Desogestrel 75 micrograms inhibits ovulation significantly more than levonorgestrel 30 micrograms (P under 0.001) in randomised double-blind comparison.^[10]
• Lactational amenorrhoea — 98 percent effective when practised correctly during the first 6 months postpartum.^[15]
• Vasectomy is not immediately effective — contraception cannot be relied on until post-vasectomy semen analysis confirms success.
• Implant shares the lowest LARC failure rate (0.27 per 100 participant-years) but unscheduled bleeding drives discontinuation.^[2][9]
• CHC VTE risk is formulation-dependent — levonorgestrel lowest at about 2.9-fold; desogestrel 6.6, gestodene 6.2 and drospirenone 6.4 versus non-users.^[5]

Exam application bank (NEET-PG / INICET)

One-line answer

Contraception methods span hormonal (combined oral contraceptive pill, progestogen-only pill, implant, injectable, hormonal intrauterine system), intrauterine (copper IUD), barrier (condom, diaphragm), natural (fertility awareness, lactational amenorrhoea), emergency contraception, and permanent sterilisation. Choice depends on efficacy, safety, side effects, reversibility, coital independence, age, comorbidities, and patient preference. Long-acting reversible contraception (LARC) — copper IUD, LNG-IUS, implant — is most effective and offered first-line. UK Medical Eligibility Criteria (UKMEC) categorise every method from 1 (no restriction) to 4 (unacceptable risk) across medical conditions.

Worked stems (answer without another resource)

Stem 1 — Classic presentation. Map symptoms to mechanism; name the first investigation and first treatment step with dose/route if drug therapy is standard. ^[1]

Stem 2 — Unstable / complicated. List red flags that force immediate resuscitation, theatre, ICU, antidote, or reperfusion — and what you do in the first 15 minutes. ^[1]

Stem 3 — Atypical group. Elderly, pregnancy, child, or immunocompromised: how presentation and thresholds change. ^[1]

Stem 4 — Differential trap. Name the three closest mimics and one discriminator for each. ^[1]

Stem 5 — Disposition. Who goes home with safety-netting, who is admitted, who needs HDU/ICU/theatre, and what follow-up is mandatory. ^[1]

Rapid viva checklist

1. Definition + classification
2. Pathophysiology chain
3. Bedside signs / criteria
4. Score with exact components (if any)
5. Emergency bundle
6. Definitive therapy with doses
7. Complications of disease and of treatment
8. Special populations
9. Guideline/trial name if classic
10. Three exam traps

Coverage self-check

If you cannot answer any stem above from this page alone, re-read the matching section — the page is intended to be self-sufficient for final-prof and NEET-PG/INICET questions on Contraception.

References16ShowHide

1. [1]Percy L The new UK Medical Eligibility Criteria (UKMEC): what has changed? J Fam Plann Reprod Health Care, 2016.PMID 27069041
2. [2]Winner B, Peipert JF, Zhao Q, et al. Effectiveness of long-acting reversible contraception N Engl J Med, 2012.PMID 22621627
3. [3]Glasier AF, Cameron ST, Fine PM, et al. Ulipristal acetate versus levonorgestrel for emergency contraception: a randomised non-inferiority trial and meta-analysis Lancet, 2010.PMID 20116841
4. [4]Trussell J Contraceptive failure in the United States Contraception, 2011.PMID 21477680
5. [5]Lidegaard O, Nielsen LH, Skovlund CW, et al. Risk of venous thromboembolism from use of oral contraceptives containing different progestogens and oestrogen doses: Danish cohort study, 2001-9 BMJ, 2011.PMID 22027398
6. [6]Shen J, Che Y, Showell E, et al. Interventions for emergency contraception Cochrane Database Syst Rev, 2019.PMID 30661244
7. [7]Kyvernitakis I, Kostev K, Nassour T, et al. The impact of depot medroxyprogesterone acetate on fracture risk: a case-control study from the UK Osteoporos Int, 2017.PMID 27461017
8. [8]Batur P, Yao M, Bucklan J, et al. Use of combined hormonal contraception and stroke: A case-control study of the impact of migraine type and estrogen dose on ischemic stroke risk Headache, 2023.PMID 36752588
9. [9]Le J, Tsourounis C Implanon: a critical review Ann Pharmacother, 2001.PMID 11261531
10. [10]Rice CF, Killick SR, Dieben T, et al. A comparison of the inhibition of ovulation achieved by desogestrel 75 micrograms and levonorgestrel 30 micrograms daily Hum Reprod, 1999.PMID 10221231
11. [11]Jensen JT, Lukkari-Lax E, Schulze A, et al. Contraceptive efficacy and safety of the 52-mg levonorgestrel intrauterine system for up to 8 years: findings from the Mirena Extension Trial Am J Obstet Gynecol, 2022.PMID 36096186
12. [12]Turok DK, Gero A, Simmons RG, et al. Levonorgestrel vs. Copper Intrauterine Devices for Emergency Contraception N Engl J Med, 2021.PMID 33503342
13. [13]Kaunitz AM Long-acting injectable contraception with depot medroxyprogesterone acetate Am J Obstet Gynecol, 1994.PMID 8178904
14. [14]Pardthaisong T, Gray RH, McDaniel EB Return of fertility after discontinuation of depot medroxyprogesterone acetate and intra-uterine devices in Northern Thailand Lancet, 1980.PMID 6102234
15. [15]Fabic MS, Choi Y Assessing the quality of data regarding use of the lactational amenorrhea method Stud Fam Plann, 2013.PMID 23720003
16. [16]World Health Organization Medical eligibility criteria for contraceptive use (5th edition) World Health Organization, Geneva, 2015.Source