I saw PCOS and to reply in case you may have other friends with PCOS or even try again later on. I was a good 90 lbs over weight, no periods, you know. I went on Medifast a weightless program. Each month I was on it I had my period! Soy increases Estrogen? IDK... But I lost 65lbs in 6 months and "miraculously" got pregnant. It never even occurred to me because I've had it for 17 years. So just an idea to pop into anyone's head if needed. Good luck to you! I know how excited you must be. I was 6 weeks when we had the first u/s and it was a dot. The tech said had I come in a day or 2 earlier she might not have seen it.
Any plan that makes you only consume their products and restricts you to 800 calories a day is atrocious for your body. That and it won't lead to long term weight loss because it doesn't solve your eating issues, it simply masks them for a short time while you follow the plan. You'll gain it back because that level of intake is not sustainable long term without causing some serious issues.
And yes, soy does increase estrogen. You should not take it without consulting a physician because it can severely screw up your cycles if you don't need excess estrogen.
PCOS doesn't doom you to being infertile. It's not any more miraculous that you got pregnant than anyone else.