Grade 1 Placental Maturity on Ultrasound: What It Means

Placental grading (Grannum classification) assesses maturity via ultrasound. Grade 1 represents early, normal development.

Grade 1 Characteristics

• Gestational age: Typically seen up to ~18–20 weeks (late 1st to early 2nd trimester).
• Appearance: Homogeneous, moderately echogenic (bright), uniform texture.
• Chorionic plate: Smooth, well-defined.
• Basal layer: Not yet clearly differentiated.
• Calcifications: Absent or minimal.

Progression Through Pregnancy

Grade	Typical Onset	Key Features
0	<18 weeks	Uniform, hyperechoic, no calcifications
1	18–29 weeks	Slight undulations on chorionic plate, rare calcifications
2	30–38 weeks	Linear calcifications on chorionic plate, indentations
3	>38 weeks	Dense calcifications, deep indentations, heterogeneous

Clinical Significance

• Grade 1 at appropriate gestation = normal.
• Premature aging (e.g., Grade 3 at 32 weeks) may signal placental insufficiency, hypertension, diabetes, IUGR.
• Always interpreted with other biometry, Doppler, and clinical context.

Discuss any concerns with your OB/GYN or maternal-fetal medicine specialist.