I’m all for honesty in a relationship. If you and your beloved wish to share that information, then more power to you. I only caution you that if you ask, you had better be prepared to accept and forgive what you might hear. If you doubt your ability to avoid judgement, jealousy and holding her past against her, you would be better off not to ask in the first place. She is with you now (and hopefully forever), and what is in the past is ancient history. I would give her the same advice about you.
Now before I get flamed for that answer - you both obviously need to be responsible if you or she feel that there may be STDs or other issues from your respective pasts that you NEED to share with each other. Only the two of you can determine what amount of responsible sharing should take place in that regard.
What I’m cautioning you about is wading into every nitty gritty detail of your beloved’s (and your) past relationships in the interest of “full disclosure”. It can be cleansing, or it can also be paralyzing. It depends upon the maturity of the individuals. You can read other threads on this forum of people who have had difficulty coping with what they were told about their partner’s past. Sometimes they have worked through it, sometimes it ended the relationship (or threatened to). Like the Boy Scouts say, “Be prepared”.
You might want to ask yourself, and pray about, just why you want to know, how you would react, and what you would do with the information. The worst thing that could happen would be for one of you to ask the other to share, then freak out over the information you have asked to hear. Sometimes ignorance is bliss.
Personally, assuming you each have made suitable repentance before God for whatever you might be less than proud of in your past, I vote to leave the past in the past and look hopefully and joyously to the future.
But then again, I’m a hopeless romantic.
Blessings.