As mentioned above, it definitely does contain protein. It's a common belief that you can avoid getting pregnant if you rinse or wipe your vagina right after sex. If the man is drinking alcohol, smoking or eating bitter things, his semen is probably going to taste that way too. Should you be eating semen or should you not? This window of time when pregnancy is possible is referred to as the "fertile window". When used correctly, condoms provide excellent protection against pregnancy and sexually transmitted infections STIsbut if you put two condoms on at once, they will rub together and there's a higher chance of condom breakage. You could have orgasm-less sex and still get pregnant.
So, if you are thinking of eating semen to get enough protein, why not just stick to the white portion of a large egg.
Can you get pregnant from that?
As mentioned above, it definitely does contain protein. If you trust your man to be in a monogamous relationship, it is probably fine to give oral sex and swallow semen. However, if you are a woman and want to give oral sex to your man and swallow his semen, keep in mind that you do put yourself at risk of getting sexually-transmitted diseases. Can you get pregnant from oral sex? Can cleaning your vagina after sex prevent pregnancy? Is it better to use two condoms instead of one? You could have orgasm-less sex and still get pregnant.