I’d be very wary about overdosing on Vitamin C to try and boost the effects of oestrogen. I’ve also heard warnings that as well as increasing the effects of some drugs it is just as likely to increase the unwanted side-effects of them.
Personally I am a great believer in getting all one’s nutrients from food, maybe I’m just a bit of a hippie. I love my food, and I eat loads of fruit, so I avoid vitamin supplements. Also some vitamin tablets may contain phyto-oestrogens which bind to estrogen receptors and inhibit the effectiveness of the oestradiol that we are taking. Phyto-oestrogen occupied receptors can't be triggered by the thousands of times stronger oestradiol (each receptor has only one slot for one molecule of hormone).
Grapefruit has been found to extend the half-life of oestradiol, the effective ingredient being a certain type of bio-flavonoid present in the inner peel and pulp of the grapefruit, but not other citrus fruits. This inhibits one of the reactions in the cytochrome p-450 steroid metabolism pathway which de-activates oestrogen. It’s also been suggested that grapefruit can inhibit enzymes created in the liver which can lead to clotting/DVT risks. Such risks though are EXTREMELY low (and possibly non-existent) from bio-identical oestradiol.
A glass of grapefruit juice or two is unlikely to do you any harm, chucking yet more tablets down your throat, well it’s not for me.
Strawberries – I love ‘em, I even grow them myself, hundreds of them. But they’re not the most vitamin C rich fruit, I know I’m being pedantic, but not by a long way. Actually I have a list of vitamin C contents in fruit (I’m such a geek) and strawbs are 22nd on the list, just above oranges, which are only slightly less rich in Vitamin C - 57 and 53mg per 100gr of fruit respectively. Rosehips contain up to 2500mg (over 40 times more!) but don’t go eating them straight off the bush, the furry seeds won’t do you any good at all. Blackcurrants, tropical guava, kiwi fruit, lychee, redcurrants, persimmon and papaya are all higher in C than strawbs, as are several other fruits which you probably will never have heard of. Give me that lot on plate over a laboratory-created tablet any day.
If I wanted to increase the effects of oestrogen though, I’d just take more oestrogen.
xx

Estradiol is good for you. So is vitamin C. I personally don’t believe more C would mean you will need less E.
Forget about substitutes for estradiol, go bio-identical (it is also made from plants, so there’s no reason to think that “herbals” are any safer), eat well, and take the dose that is right for you.
Believe the following statement:
“The only way to truly impact hormone levels is to take hormones.”
From: http://www.aeron.com/news[...]er_.htm
Soy is not a hormone, nor is liquorice, black cohosh or kwao quack krap.
Reports which tell us hormones are potentially risky are based on old studies conducted using Premarin and Provera, which should be avoided. They are not bio-identical, and are no longer the only choice of hormone available.
Human oestrogen is what causes women to feminise, estradiol is the strongest of the 3 types of oestrogen. The term bio-identical means it is identical to human oestrogen. It’s not dangerous, it does exactly what it says on the tin:
E S T R A D I O L
Half the planet can’t be wrong.
xx