ANSWER: C

Rationale:

In a woman with migraine with aura, an estrogen-containing combined contraceptive should be avoided. The ethinyl estradiol (EE) component of combined hormonal contraceptives increases the risk of ischemic stroke, and migraine with aura is itself an independent risk factor for ischemic stroke; combining the two produces an unacceptable compounded risk, and combined hormonal contraceptives are classified as an unacceptable health risk in this setting. The appropriate options are estrogen-free: a progestin-only pill, the levonorgestrel intrauterine device, the etonogestrel implant, or a non-hormonal method (such as a copper intrauterine device), all of which avoid the EE-associated stroke risk.

• Option A: Option A is incorrect because migraine with aura is highly relevant to estrogen-containing contraceptive selection regardless of smoking status; the EE-associated ischemic stroke risk applies even in a nonsmoker with aura.
• Option B: Option B is incorrect because a higher EE dose increases rather than decreases stroke risk; raising the estrogen dose does not stabilize cerebral vasculature and would worsen the contraindication.
• Option D: Option D is incorrect because drospirenone's anti-mineralocorticoid activity has no effect on the ischemic stroke risk conferred by the EE component; pairing EE with any progestin does not make the combination acceptable in migraine with aura.
• Option E: Option E is incorrect because contraceptive patches deliver ethinyl estradiol systemically and do not eliminate the EE-associated stroke risk; the transdermal route of a combined hormonal contraceptive does not make it safe in migraine with aura, and the patch is not preferred here.

ANSWER: A

Rationale:

In a woman who is 35 years of age or older and smokes 15 or more cigarettes per day, an estrogen-containing combined contraceptive should be discontinued in favor of a progestin-only or non-hormonal method. Ethinyl estradiol increases the synthesis of hepatic coagulation factors and raises the risk of venous thromboembolism, and the combination of older age and heavy smoking adds substantial arterial cardiovascular risk (myocardial infarction and stroke). The convergence of these risks makes continued use of an EE-containing combined contraceptive an unacceptable health risk in this patient, and an estrogen-free method is appropriate.

• Option B: Option B is incorrect because tolerating the combined contraceptive without an event for several years does not establish immunity to thrombotic complications; the elevated risk from age and smoking is ongoing and cumulative, and prior uneventful use does not justify continuation.
• Option C: Option C is incorrect because a higher ethinyl estradiol dose increases, rather than offsets, the thrombotic and cardiovascular risk; raising the estrogen dose in a 38-year-old smoker worsens the problem.
• Option D: Option D is incorrect because low-dose aspirin does not neutralize the hepatic procoagulant effects of ethinyl estradiol or eliminate the arterial risk associated with smoking; adding aspirin is not a substitute for discontinuing the estrogen-containing method.
• Option E: Option E is incorrect because the cardiovascular and thrombotic risk associated with smoking and ethinyl estradiol is not limited to same-day simultaneous exposure; smoking confers sustained vascular risk, and intermittent timing of cigarettes around pill dosing does not mitigate it.

ANSWER: D

Rationale:

Carbamazepine is an enzyme-inducing antiepileptic drug that increases hepatic CYP3A4 activity and accelerates the metabolism of ethinyl estradiol and oral progestins, reducing their plasma concentrations and risking contraceptive failure. For this reason, methods whose efficacy depends on systemic oral hormone levels (combined oral contraceptives and progestin-only pills) are less reliable in women on enzyme-inducing antiepileptics. The levonorgestrel intrauterine device, whose contraceptive effect is largely a local endometrial action, and depot medroxyprogesterone acetate, whose depot serum levels are high and sustained, are considered more robust to enzyme induction and are preferred options. A copper intrauterine device (non-hormonal) is also appropriate.

• Option A: Option A is incorrect because a low ethinyl estradiol dose does not overcome carbamazepine's potent CYP3A4 induction; a 20-microgram pill is, if anything, more vulnerable to induction-related failure, not less.
• Option B: Option B is incorrect because oral progestins are metabolized by CYP3A4 and are therefore affected by carbamazepine; progestin-only pills are not immune to enzyme induction and are not the most reliable option in this setting.
• Option C: Option C is incorrect because a clinically important interaction does exist: carbamazepine induces CYP3A4 and reduces hormonal contraceptive efficacy, so additional precautions or a more robust method are required.
• Option E: Option E is incorrect because contraceptive patches deliver ethinyl estradiol systemically and the absorbed hormone is still metabolized by induced hepatic CYP3A4; the transdermal route does not bypass the liver in a way that protects against enzyme induction, so the patch is not preferred in women on carbamazepine.

ANSWER: B

Rationale:

Low-dose vaginal estrogen preparations (cream, suppository, or ring) act primarily on the vaginal and urogenital mucosa to relieve genitourinary syndrome of menopause, and at standard low doses they produce minimal systemic absorption — for example, the low-dose vaginal insert delivers serum estradiol levels near the postmenopausal baseline. They are generally considered acceptable for genitourinary symptoms when systemic absorption is minimal. In a breast cancer survivor, however, the decision should be individualized and made together with her oncology team, because oncological guidance varies by individual risk and tumor characteristics. This balances symptom relief against the goal of minimizing systemic estrogen exposure.

• Option A: Option A is incorrect because low-dose vaginal estrogen does not produce systemic estradiol concentrations equal to oral hormone therapy; systemic absorption at standard low doses is minimal, and it is not absolutely contraindicated in all breast cancer survivors.
• Option C: Option C is incorrect because the therapeutic goal of low-dose vaginal estrogen is local mucosal effect with minimal systemic absorption; it does not relieve symptoms by raising systemic estradiol to premenopausal levels, and doing so would be undesirable in this patient.
• Option D: Option D is incorrect because systemic oral estrogen is not the preferred first-line treatment for isolated genitourinary symptoms, especially in a breast cancer survivor; local low-dose vaginal therapy targets the symptoms with far less systemic exposure than systemic estrogen.
• Option E: Option E is incorrect because a combined oral contraceptive containing ethinyl estradiol is inappropriate here: the progestin does not protect the breast, the estrogen is systemic, and high-dose systemic contraceptive estrogen is not a treatment for isolated genitourinary atrophy in a postmenopausal breast cancer survivor.

ANSWER: E

Rationale:

In a postmenopausal woman with an intact uterus, a progestin must be added to systemic estrogen therapy. Unopposed estrogen stimulates endometrial proliferation through endometrial estrogen receptors and substantially increases the risk of endometrial hyperplasia and endometrial carcinoma. The progestin opposes estrogen-driven endometrial proliferation (promoting secretory transformation and limiting growth), thereby providing endometrial protection. This is why combined estrogen-progestin regimens are standard for women with a uterus, whereas estrogen-only therapy is reserved for women who have had a hysterectomy.

• Option A: Option A is incorrect because systemic estrogen does stimulate the postmenopausal endometrium; the endometrium remains estrogen-responsive after menopause, which is precisely why unopposed estrogen is hazardous in a woman with a uterus.
• Option B: Option B is incorrect because the progestin must be given concurrently from the start for endometrial protection, not withheld until abnormal bleeding occurs; waiting for bleeding would permit unopposed estrogenic stimulation and hyperplasia.
• Option C: Option C is incorrect because the progestin is added for endometrial protection, not to relieve vasomotor symptoms; estrogen is the effective treatment for hot flashes, and the progestin's role here is to protect the endometrium.
• Option D: Option D is incorrect because both oral and transdermal systemic estrogen reach and stimulate the endometrium through the systemic circulation; the need for a progestin depends on the presence of a uterus, not on the route of estrogen administration. Option E is correct as explained above.

ANSWER: A

Rationale:

For a woman with polycystic ovary syndrome and androgenic symptoms (hirsutism and acne) who desires contraception, a combined oral contraceptive pairing ethinyl estradiol with an anti-androgenic progestin (such as drospirenone or cyproterone acetate) is pharmacologically most appropriate. Ethinyl estradiol induces hepatic sex hormone-binding globulin, which binds testosterone and lowers the free (bioactive) androgen fraction, while the anti-androgenic progestin antagonizes the androgen receptor in skin and pilosebaceous units. Together these actions reduce hirsutism and acne while providing cycle regulation and contraception.

• Option B: Option B is incorrect because a levonorgestrel progestin-only pill has androgenic activity that would tend to worsen, not improve, hirsutism and acne, and it does not provide the sex hormone-binding globulin rise that lowers free testosterone.
• Option C: Option C is incorrect because levonorgestrel has a high androgenic index and does not suppress ovarian androgen production through androgenicity; pairing ethinyl estradiol with levonorgestrel is less favorable for androgenic symptoms than pairing it with an anti-androgenic progestin.
• Option D: Option D is incorrect because a high-dose estrogen-only pill is inappropriate in a woman with a uterus (unopposed estrogen risks endometrial hyperplasia), and the claim that a progestin worsens androgenic symptoms in every case is false — anti-androgenic progestins improve them.
• Option E: Option E is incorrect because depot medroxyprogesterone acetate does not have meaningful glucocorticoid-mediated adrenal androgen suppression that resolves hirsutism, and it is not the most appropriate first choice for androgenic symptoms; an ethinyl estradiol plus anti-androgenic progestin combination is preferred.

ANSWER: C

Rationale:

Both drospirenone (a progestin derived from spironolactone) and spironolactone itself antagonize the mineralocorticoid receptor, producing potassium-retaining (anti-mineralocorticoid) effects. When the two are combined, their potassium-retaining actions are additive and increase the risk of hyperkalemia, so serum potassium should be monitored. In a young patient with normal renal function the absolute risk is relatively low, but monitoring remains appropriate because the additive mechanism is real, and the risk rises substantially if renal impairment or other potassium-retaining drugs are present.

• Option A: Option A is incorrect because drospirenone and spironolactone share the same anti-mineralocorticoid mechanism (both antagonize the mineralocorticoid receptor), so they do have an overlapping effect on potassium and monitoring is warranted.
• Option B: Option B is incorrect because drospirenone and spironolactone are not chemically identical; drospirenone is a spironolactone-derived progestin used for contraception, while spironolactone is an aldosterone antagonist, and they are used together intentionally for their anti-androgenic effects with potassium monitoring, not avoided as a redundant double dose.
• Option D: Option D is incorrect because spironolactone does not inactivate ethinyl estradiol or cause contraceptive failure; it is not contraindicated with combined oral contraceptives, and the relevant consideration is potassium monitoring, not loss of contraceptive efficacy.
• Option E: Option E is incorrect because the combination produces a risk of hyperkalemia (not hypokalemia), so switching to an androgenic levonorgestrel pill to prevent hypokalemia is based on a false premise; the appropriate action is potassium monitoring, not a change motivated by preventing potassium loss.

ANSWER: D

Rationale:

For luteal phase support in in vitro fertilization, vaginal or intramuscular progesterone is preferred over oral progesterone. Oral progesterone undergoes extensive hepatic first-pass metabolism, giving it low and highly variable bioavailability (micronized progesterone reaches only approximately 10 to 15 percent), which is insufficient to reliably achieve the high, sustained progesterone levels and endometrial exposure needed for luteal support. Vaginal progesterone bypasses first-pass and produces favorable local endometrial concentrations (a uterine first-pass effect), and intramuscular progesterone also bypasses first-pass to give reliable sustained systemic levels. These routes therefore provide the dependable therapeutic exposure required after embryo transfer.

• Option A: Option A is incorrect because oral micronized progesterone does not have approximately 90 percent bioavailability; its oral bioavailability is only about 10 to 15 percent because of extensive first-pass metabolism, which makes it less reliable for luteal support than vaginal or intramuscular routes.
• Option B: Option B is incorrect because medroxyprogesterone acetate is a synthetic progestin, not bioidentical progesterone, and is not the agent used for luteal phase support; vaginal or intramuscular progesterone is the standard.
• Option C: Option C is incorrect because a combined oral contraceptive is not used for luteal phase support after embryo transfer; it contains estrogen and a synthetic progestin and is designed to suppress ovulation, not to support an early pregnancy.
• Option E: Option E is incorrect because luteal phase progesterone support is routinely required in stimulated in vitro fertilization cycles, where the corpus luteum function is often inadequate due to the effects of ovarian stimulation and pituitary suppression; relying on endogenous corpus luteum progesterone alone is not adequate.

ANSWER: B

Rationale:

Efavirenz is a non-nucleoside reverse transcriptase inhibitor that is a potent CYP3A4 inducer. It substantially reduces ethinyl estradiol and progestin plasma levels and can compromise the efficacy of combined hormonal contraceptives, increasing the risk of contraceptive failure. The appropriate approach, made in consultation with her HIV provider, is to recognize this interaction and either switch to an integrase strand-transfer inhibitor-based regimen (dolutegravir, raltegravir, or bictegravir do not impair contraceptive efficacy and are preferred in women needing reliable hormonal contraception) or use a contraceptive method less affected by enzyme induction or add a reliable non-hormonal backup method.

• Option A: Option A is incorrect because efavirenz does interact with hormonal contraceptives — it is a potent CYP3A4 inducer that lowers contraceptive hormone levels — so starting a standard pill without any change or precaution risks contraceptive failure.
• Option C: Option C is incorrect because doubling the ethinyl estradiol dose is not an established, reliable strategy to overcome efavirenz induction and increases estrogen-related risks; modifying the regimen or method is preferred.
• Option D: Option D is incorrect because deliberately adding a CYP3A4 inhibitor such as ketoconazole to manipulate contraceptive levels is not appropriate management; it introduces additional drug interactions and toxicity risk and is not how this interaction is handled.
• Option E: Option E is incorrect because efavirenz induces (not inhibits) CYP3A4 and therefore lowers, rather than raises, ethinyl estradiol levels; advising a lower-dose pill to avoid estrogen excess is based on the wrong direction of the interaction.

ANSWER: E

Rationale:

Ethinyl estradiol potently induces UGT1A4, the enzyme that glucuronidates and inactivates lamotrigine. When a combined oral contraceptive containing ethinyl estradiol is started, lamotrigine plasma levels fall by approximately 40 to 65 percent, increasing the risk of breakthrough seizures. The correct anticipatory management is therefore to plan for a likely increase in the lamotrigine dose at the time the pill is started, monitor the patient for breakthrough seizures, and plan to reduce lamotrigine again if the pill is later discontinued (because levels will rebound and could cause toxicity). Coordinating this with the neurologist is appropriate.

• Option A: Option A is incorrect because ethinyl estradiol and lamotrigine do interact: ethinyl estradiol induces UGT1A4, the major lamotrigine-metabolizing enzyme, so a change in lamotrigine dosing must be anticipated.
• Option B: Option B is incorrect because ethinyl estradiol induces (not inhibits) lamotrigine metabolism, so lamotrigine levels fall rather than rise; decreasing the dose at pill initiation would worsen the seizure risk.
• Option C: Option C is incorrect because lamotrigine can be combined with hormonal contraception using anticipatory dose adjustment, or by choosing a progestin-only or non-hormonal method; relying on emergency contraception every cycle is not appropriate management.
• Option D: Option D is incorrect because lamotrigine does not induce ethinyl estradiol metabolism; the interaction runs in the direction of ethinyl estradiol lowering lamotrigine, so increasing the ethinyl estradiol dose is not the correct response.

ANSWER: A

Rationale:

In a 58-year-old woman with hypertension and an elevated body mass index but no thrombosis history, transdermal estradiol is the preferred route to minimize thrombotic risk. Transdermal estradiol is absorbed directly into the systemic venous circulation, bypassing portal hepatic first-pass, and therefore produces minimal increases in hepatic coagulation factors; observational data show no increased venous thromboembolism risk with the transdermal route, in contrast to oral estrogen. This advantage is meaningful because her age and elevated body mass index already raise her baseline thrombotic risk. The Women's Health Initiative used oral conjugated equine estrogens and informed concerns about thromboembolic and cardiovascular risk with oral therapy, reinforcing the preference for the transdermal route in higher-risk women.

• Option B: Option B is incorrect because the Women's Health Initiative did not show that oral estrogen lowers venous thromboembolism risk relative to transdermal estradiol; oral conjugated equine estrogens were associated with increased thromboembolic risk, and transdermal estradiol is the lower-risk route.
• Option C: Option C is incorrect because high-dose oral ethinyl estradiol (a contraceptive-strength estrogen) carries greater thrombotic risk, not lower, and is inappropriate for menopausal symptom management in a 58-year-old; menopausal hormone therapy uses much lower estrogen doses.
• Option D: Option D is incorrect because the route of estrogen does affect thrombotic risk (oral first-pass stimulates hepatic coagulation factors while transdermal does not), so the choice is not thrombotically neutral, and the Women's Health Initiative does provide relevant guidance.
• Option E: Option E is incorrect because estrogen therapy is not absolutely contraindicated in a 58-year-old woman with well-controlled hypertension and no thrombosis history; transdermal estradiol is a reasonable option, and well-controlled hypertension alone does not make all hormone therapy absolutely contraindicated.