Nasal BoneBone and BonesDown SyndromeNasal MucosaCrown-Rump LengthUltrasonography, PrenatalNuchal Translucency MeasurementCell WallPregnancy Trimester, FirstBone RemodelingPregnancy Trimester, SecondBone DensitySkull FracturesNasal PolypsNasal SeptumGestational AgePregnancyBone ResorptionMaternal AgeBone MarrowChorionic Villi SamplingNasal Lavage FluidChromosomes, Human, 16-18Chorionic Gonadotropin, beta Subunit, HumanPregnancy-Associated Plasma Protein-ANose Deformities, AcquiredBone NeoplasmsBone Marrow CellsBone DevelopmentImaging, Three-DimensionalBone DiseasesNoseNasal DecongestantsChromosomes, Human, 13-15Facial BonesBone RegenerationBone MatrixObserver VariationBone Marrow TransplantationBone TransplantationPregnancy, High-RiskFetal Diseases