Alternatively, the Prostitute Pro. It also prevents pregnancy but doesn't make Steele infertile. You can access Heat scenes without getting pregnant this way.
For male parts, you can use Inseminator Pro. Use the Codex app (Extra) to reduce Virility to 0.
Sterilex is the easiest. It's available immediately (from T1-KA on FIRST-14 or vending machines on most planets). If you take 3 at once, you'll be infertile until you take a dose of
Fertite+.