OPP-Should This Birth Mother Contact Her?

A birth mother wants to know what is the appropriate way to reach out the baby girl she gave up for adoption 23 years ago.

Mike & Kate-
I got pregnant when I was 16 and gave the baby up for adoption. It was an open adoption but I have never heard from the family or from my daughter. The family she was adopted by lived out of state. I was a peace with my decision knowing that the family she was placed with could provide a much better live for her than I could at 16.
I went on to get married and have two more children. My family knows about the daughter I gave up. There is not a day that goes by that I don't think about her. She is 23 years old and just graduated from college in December. I know this because I found her on Facebook. For the last 6 months I have been checking out her page. I haven't friended her so I can't see everything.
After doing lots of reflection over the holidays, I have decided I want to contact her. I want her to understand why I made the choice I did. I am not wanting to play Mom. I understand that she had a wonderful woman who raised her. I just want to get to know her. Now that she is an adult, I want to be friends. Even if we just meet once, maybe I can provide an answer to any questions she has. I'm even willing to meet her parents and thank them for raising such an amazing daughter. I know she knows she is adopted because I saw a post about adoptive children on her page. So I wouldn't be surprising her with this news.
I'm wondering if anyone else who has given up a child for adoption has used Facebook to find them? As an adoptive child, would you want to be contacted through Facebook by your birth parent?
Or should I contact her through the adoption agency?
Or should I wait and hope that she contacts me since it was an open adoption? I'm not sure I can't wait any longer. Any advice would be greatly appreciated.

A mother in waiting.

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