Would it be a sin to sleep with a prostitute and use contraceptives?

Query by Hollywood Jono: Would it be a sin to sleep with a prostitute and use contraceptives?
Supposedly sleeping with a prostitute is the lesser of two evils for a man as opposed to masturbating. That explained if you use contraceptives and shield oneself from sexually transmitted diseases would not this be the same issue as squandering your seed by way of masturbation?

Ideal solution:

Reply by suzie the pilgrim
Indeed. Adultery and fornication.

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