Columbia subject headings:
Abnormalities, Human--Congresses.
Fetus--Abnormalities--Congresses.
Human chromosome abnormalities--Congresses.
Teratogenic agents--Congresses.
Harvard subject headings:
Abnormalities, Human--Congresses.
Fetus--Abnormalities--Congresses
Human chromosome abnormalities--Congresses.
Teratogenic agents--Congresses.
Princeton subject headings: