Concepedia
Prenatal Diagnosis · 1998 · 72 citations · 0 references
MedicineMaternal HealthObstetricsObstetric UltrasoundUltrasonographyUltrasoundDown SyndromeFirst-trimester UltrasoundObstetric UltrasonographyPregnancy DiagnosisFirst Trimester UltrasonographyFirst-trimester Pregnancy Ultrasound