Hey Lisa

they are great questions!
you can choose to have your placenta birthed without the injection (which is synthetic oxytocin to help the uterus to contract and push the placenta out)...this method takes anwhere from 5-30 minutes or so for the placenta to naturally peel off the uterus wall and for you to push it out...which isnt like pushing your baby out, more like a feeling of a fullness in your vagina, and with a little push, or sometimes a cough, the placenta plops out
many Drs prefer you to have the injection...to decrease the risk of postpartum bleeding...but if you have not had any complications in pregnancy or labor to suggest that you may be at risk for this...then you dont have to have it...but do let your doctor know in advance, and write it in your birth plan so the midwives at the hospital are aware as well

yep its true that breaking your waters van help move labor along, and sometimes this is necessary if your labor has been overly prolonged and you are tired. Generally speaking though the body will move at its own pace...which is the pace which is perfect for you and your baby

once you have anything done at all to you in labor...intervention...it sets off a snowball affect (called the cascade of intervention)...basically one thing gets done...then another...then another

hope this helps...feel free to ask any questions...I LOVE talking all things, belly birth and baby

x