Final answer:
The correct prefix to be added to -ceptive to create a term that describes something that works against conception is O contra-.
Step-by-step explanation:
The correct prefix to be added to -ceptive to create a term that describes something that works against conception is O contra-. This prefix has a Latin origin and means 'against' or 'opposite of'. For example, the term 'ocontraceptive' describes something that works against conception.
Learn more about Prefixes and their meanings in English