Just curious, why prenatal as opposed to a good two a day women's multi? Breast development perhaps?
Personally I lean towards doing what I can in terms of longevity so I take a mishmash of supplements.
Men's two a day multi (pre-HRT will switch when I start changing up my body chemistry)
--contains resveratrol -an antioxidant found in grape skins that has been shown to produce life expectancy increases similar to that of caloric restriction
Fish oil high in EPA & DHA
Calcium/vitamin D
Red yeast rice - natural source of lovastatin which is a cholesterol reducing drug
Coenzyme Q10 - required as part of cell metabolism and when combined with good fats has been shown to increase life expectancy in rats
Phosphatidylcholine - essential component in cellular membranes, sagging skin tends to be low in content
Grape seed extract - antioxidant and anti-inflammatory, also has a bunch of other benifits to cardiovascular health
I have looked into biotin and most of the research I've seen suggests that it's normal biosynthesis pathway is sufficient for the body to maintain good heath, and is usually only supplemented in cases of deficiency or diabetes.