Ah the Colonial Marine corps, it's a hard life, rescuing tasty colonists daughters from their virginities. Or at least that's what you think when you sign up, before you face your first xenomorph. Then my friend, you're likely to find yourself mercilessly hunted down and having your skull and spine torn out to adorn some alien SoB's fireplace and thats if your lucky. The unlucky ones get to make sloppy alien face love and then carry an alien baby complete with all symptoms, sensitive nipples, ankle bloating, and having your little tyke eat its way out of your chest before you've even been to your first ultrasound.
Here, this instructional video will help you understand whats required of you in the glorious Colonial Marine Corps.