Well, they don't have rusty nails in them... or dirty needles... or broken pieces of glass, so I wouldn't call them DANGEROUS ... lol. (sorry, my brain is stuck on funny today)
Any substance no matter how safe can be used in a way that can cause harm. You can poison yourself by drinking too much water for instance (don't panic... you have to drink gallons for this to happen). So, yes, used incorrectly both of these herbs can be a problem.
Side effects are always going to happen. You will never take an herb or a drug that just has one action. They always produce several actions.
To be specific to the herbs you have mentioned:
Saw Palmetto... it is used by men for the health of their prostate gland. It does this by reducing testosterone (that is the simple explanation). It can also lower testosterone levels in women. This is why some women find it helpful in NBE. It can cause acne in some and I think the most common side effect is weight gain. Those are not very 'happy' side effects, but they are not dangerous.
Fenugreek... it is used by women to enhance milk production, so it is considered a galactogogue. Galactogogues stimulate the production of glandular tissue in the breast, so they can be useful for NBE. One of the other things fenugreek has been used for is lowering blood sugar. Some women feel this effect with rather low dosages and some women are not bothered by this at all. However, low blood sugar can be an issue - so although I do not consider this a dangerous herb, it can be dangerous for the wrong person.
So, basically these are not dangerous herbs unless you take them at higher than normal levels, you are allergic to them or you have a problem with low blood sugar.
thanks for your answers..
i heard that SP causes cellulite and some people prefer not ot take them so i have decided to not take SP.
I want to take only fenugreek capsules and wild yam cream..is this enough or should i also take fennel with it?
Do the hormone test to see what sort of imbalance you have and therefore what sort of herbs you need. If you have excess testosterone you could add nettle root which works the same as SP but dosn't cause weight gain.