One woman doesn’t want to buy the moon theory described, though she will look into the herbal solution. The thing is, the moon theory only works after you’ve made it work, and there are things you can do to become synchronized with the moon phases (unless you have insurmountable menstrual glitches.) Looking at the moon a lot (sounds freaky, but it’s true) and regulating the light in your bedroom are just 2 things. If it could work for you, you’d simply have more confidence in your birth control because you’d know more assuredly when you are ovulating.
The book “Herbal for the Childbearing Year” deals a lot with herbal contraception. There are herbs that promote temporary sterility, like stonessed root, jack-in-the-pulpit root, and thistles (some of these are very powerful so you would have to first research exactly how to use them); and there are “implantation preventers” which make the uterus unsuitable for a fertilized egg to grow in.
Carrot seed, Rutin, and smartweed leaves all prevent implantation. It may be very worthwhile for you to look into these options, if having a baby is not possible for you right now. There are also ecbolics listed (herbs that cause abortions) but if you are against abortion, you want to stay away from them.