Cervical Length MeasurementObstetric Labor, PrematureCervix UteriFibronectinsUterine Cervical IncompetenceCervical RipeningUltrasonography, PrenatalPregnancyVaginaGestational AgeCerclage, CervicalTocolytic AgentsPregnancy Trimester, SecondLabor Stage, FirstPregnancy, ProlongedHysteroscopyUltrasonographyLabor OnsetOvarian CystsPregnancy, High-RiskSensitivity and SpecificityPremature BirthTwinsUterine HemorrhageExtraembryonic MembranesPregnancy Trimester, ThirdLabor, InducedPredictive Value of TestsUterine DiseasesPregnancy, TripletPregnancy OutcomePregnancy Trimester, FirstReceptors, FibronectinProspective StudiesCesarean SectionUltrasonography, Doppler, ColorGravidityDouglas' PouchMultiphasic ScreeningDilatation and CurettageOvarian DiseasesAdnexal DiseasesPregnancy, EctopicAbortion, ThreatenedTocolysisPregnancy, TubalAdenomyosisEndometriumROC CurveEndosonographyAbortion, IncompletePlacenta PreviaPregnancy, MultipleReproducibility of ResultsObserver VariationParityUltrasonography, DopplerDelivery, ObstetricUterusFetal Membranes, Premature RuptureFetusCA-125 AntigenEndometriosisPlacenta, RetainedPolypsAbortifacient Agents, NonsteroidalAbortion, MissedEndometrial NeoplasmsPalpationImaging, Three-DimensionalHydroxyprogesteronesBiological MarkersUltrasonicsOvarian NeoplasmsInfant, NewbornPolyhydramniosInfertility, FemaleUterine NeoplasmsLeiomyomaTripletsPostmenopauseRisk AssessmentOvarian FollicleUterine ContractionPessariesAmniocentesisOvaryAbortion, SpontaneousFetal HeartFertilization in VitroRisk FactorsUltrasonic TherapyGlycoproteinsUltrasonography, InterventionalAdministration, IntravaginalHysterectomyLaparoscopyFollicular PhaseTime FactorsReference Values