eta- also, having read the reviews on the MMH site (I love MMH products, btw), I do have to mention that my labors WITHOUT any pre-birth formulas have been very similar to a lot of the ones written about...I'm always VERY dilated and effaced once I start (5-6cm...actually VERY high overall Bishop scores), contractions are quite manageable, I labor quietly and in control, no bleeding during birth and then once placenta is out I have very minimal bleeding compared to many others, and I've loved each birth experience because they were so awesome. So I'm not sure if a formula would even change anything for me? However, I've never gone "on my own" (without castor oil...which has worked great and easily for me without complication, and is not up for discussion ) before 40+ weeks.
Me (27) DH (30)...9 Years
DD (7) ~ DD (4) ~ DS (3)
Babies in Heaven... 9/04 2/05 3/11 4/11 6/11 11/11 2/12 (along with my tube )
Sounds like you don't really need a birth prep. I don't think I need one this time either. My last labor (2nd child, a VBAC, so first vaginal birth) was 2 hours. I took the birth prep and went into labor at 39 weeks, hours after doing rebozo sifting to get her better situated. I take EPO and will do that again, but I wouldn't mind a slightly slower labor so it'll be easier on myself and my baby.
I'd never heard of it lengthening gestation. I don't believe at all that it makes you go into labor sooner than your body is ready, but I believe taking it can help to have "all systems go" so that when the right things kick in to start labor, labor will be efficient.
I used Dr. Christopher's 6 week birth prep. At most, I'd take it for a couple weeks but no longer, since I want to slow things down a little.