Contraceptives, OralContraceptives, Oral, CombinedContraceptives, Oral, HormonalContraceptives, Oral, SyntheticContraceptive AgentsEthinyl EstradiolContraceptive Agents, FemaleMestranolNorgestrelDesogestrelNorethindroneContraceptionLevonorgestrelContraceptive DevicesContraceptive Devices, FemaleContraception BehaviorIntrauterine DevicesEthynodiol DiacetateLynestrenolContraceptive Agents, MaleNorpregnenesNorethynodrelFamily Planning ServicesMenstruationHormonesContraceptives, PostcoitalProgestinsEthinyl Estradiol-Norgestrel CombinationAndrostenesMenstrual CycleFollicle Stimulating HormonePregnancyMegestrolParityPregnancy, UnplannedContraceptives, Oral, SequentialMedroxyprogesterone AcetateLuteinizing HormoneThyroid HormonesGonadal Steroid HormonesProgesterone CongenersEstrogensSterilization, ReproductiveEstradiol CongenersMenstruation DisturbancesVaccines, ContraceptiveXanthurenatesGonadotropin-Releasing HormoneRisk FactorsCase-Control StudiesPregnancy, UnwantedHormone Replacement TherapyReproductive HistorySterilization, TubalParathyroid HormoneOvulation InhibitionAbortion, InducedMetrorrhagiaMenopauseAge FactorsTime FactorsEstradiolThromboembolismNorpregnadienesMenarcheAmenorrheaSpermatocidal AgentsContraception, PostcoitalIntrauterine Devices, MedicatedVenous ThrombosisUterine HemorrhageReceptors, Thyroid HormoneIntrauterine Devices, CopperPyridoxineHuman Growth HormoneDysmenorrheaContraception, ImmunologicProgesteroneChlormadinone AcetateTransdermal PatchMedroxyprogesteroneThrombophlebitisDrug InteractionsAdrenocorticotropic HormoneAcne VulgarisCyproterone AcetatePremenopauseBreast NeoplasmsRiskPituitary HormonesHealth Knowledge, Attitudes, PracticeContraceptive Devices, MaleContraceptives, Postcoital, HormonalFertilityAnti-Mullerian HormoneTestosteroneEstrogen Replacement TherapySmokingMegaloblastsOdds Ratio