I would not induce labor for any reason other than medical necessity. I would not use herbs or any other "natural" induction method unless I were overdue, and going to be transferred into a high-risk group (for medical induction in a hospital) if labor did not begin.
This month is National Prematurity Awareness Month, and the March of Dimes is very involved in this, and has a lot of information about it on their website here (http://www.marchofdimes.com/aboutus/49267_62082.asp); and specifically, stuff about late preterm and term fetal development here (http://www.marchofdimes.com/pnhec/240_48590.asp).
Among the considerations are brain development (at 35 weeks, the brain is 2/3 the weight of the brain at 39 weeks!), lung development, and from the MoD website:
Here’s why your baby needs 39 weeks:
* Important organs, like his brain, lungs and liver, get all the time they need to develop.
* He is less likely to have vision and hearing problems after birth.
* He has time to gain more weight in the womb. Babies born at a healthy weight have an easier time staying warm than babies born too small.
* He can suck and swallow and stay awake long enough to eat after he’s born. Babies born early sometimes can’t do these things.
Most first-time moms will give birth around 41 weeks 1 day. You sound like you might go a little earlier than that, but you still probably have 2-3 weeks to go -- babies tend to "drop" about 3 weeks before birth in first-time moms, but they may not drop before labor begins in subsequent pregnancies.
Induced labors (even "naturally" induced ones, if there can be such a thing!) are harder on you *and* your baby than natural labors. You have no good medical reason to try to induce labor, so just let your baby continue to grow inside you, and reach her full prenatal potential, for the easiest transition to life on the outside.
I know these last few weeks are hard to take -- you're wanting so badly to meet your little girl after all this time, and you wish you could push a fast-forward button on life! But you can't; and you may cause more harm than good if you did. And I can ***guarantee*** you, it is far easier to take care of your baby now than after she is born, so enjoy these last few weeks of her being inside you; enjoy the kicks -- they'll be gone soon enough; enjoy the rolling and rumbling of her inside you; enjoy how effortless it is to take care of her now (no crying, no gas, no diapers, no nursing) compared to after she is born.