Oh, I didn't see that. I think the way the pregnancy system works is every time you get raped, there's a chance you might end up pregnant. From what I gather from the translation, for this demo version that's currently up for download right now, the chance of getting pregnant is significantly higher than it will be in future updates. You'll notice if you use the button that normally ended the game if you ran out of life (E I think) in previous versions before you're out of health, it will ask if you want to put up an escape flag or something. If you say yes, at any point you can leave the stage by going to the left most side of the map. I just went through each stage and let the character get pewpew'ed in a few times and then ran away.
You'll notice on the menu stage select screen, under the gun and suit customization options, there's a new option for the Medical Center. When the prompt comes up, hit yes. After showing her in the green tube, it will determine if you're impregnated by something. If you aren't, it will just go back to the menu screen. If you are, it will go on to another scene with her in the lab chair. I don't think you can fail this part, but you basically just mash on the movement keys to help the doctor get the little sucker out of you.