Pathophysiology
Clinical meaning
The NP applies the CDC US Medical Eligibility Criteria (US MEC) for contraceptive prescribing, integrates HRT risk-benefit analysis, manages UTI prophylaxis, ensures adequate prenatal supplementation, and maintains awareness of teratogenic medications. The US MEC classifies contraceptive safety into 4 categories: Category 1 (no restriction), Category 2 (advantages generally outweigh risks), Category 3 (risks generally outweigh advantages -- method not usually recommended), and Category 4 (unacceptable health risk -- method contraindicated). Key US MEC Category 4 conditions for combined hormonal contraceptives (CHCs) include: smoking 15+ cigarettes/day in women over 35, current or history of VTE/PE, known thrombogenic mutations, current or history of ischemic heart disease or stroke, migraine with aura at any age, breast cancer (current), complicated valvular heart disease, and systolic BP 160+ or diastolic 100+. Progestin-only methods (pills, implant, IUD, injection) have fewer Category 4 restrictions, making them safer for many women with CHC contraindications. Hormone replacement therapy (HRT) decision-making integrates the WHI findings: combined estrogen-progestin HRT increases VTE risk (HR 2.06), stroke risk (HR 1.41), and breast cancer risk after approximately 5 years of use (HR 1.26); estrogen-only...