It's not the semen itself, I think it's the physical exercise. They also say walking (like walking on a sandy beach) will induce your labor. Good luck!

They say the orgasm could help induce labor plus they say semen can help thin out your cervix

Yes but it doesn't really induce labor. it helps to soften your cervix.

Yes it can but its not as effective as the induction methods they use @ hospitaals