Ka D'Argo examines a contraceptive shield
Contraceptive shields were devices created by the Peacekeepers to prevent Leviathan biomechanoids from bearing offspring.
One of these shields was installed on Moya during experiments conducted upon her under the supervision of Bialar Crais. This shield was later damaged by Ka D'Argo, while investigating what damage the Leviathan had undertaken. This allowed Moya to conceive Talyn.
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A contraceptive shield is seen in Farscape.