Mittlesmirz

Has your doctor ruled out PCOS (polycycstic ovarian syndrome)? That pain might be a symptom of that.I've just found out I have PCOS but I'm not having any more babies. Just google PCOS and look at the symptoms - irregular periods (or not), hair thinning, acne, weight gain, etc. PCOS makes it harder to get pregnant. Hope that helps.

I have no experience with the mittlething but I am RH negative as well. Do you already have a child and looking to get pregnant again? Did you get the Rhogam shot? If so, no worries and no issues getting pregnant except that it is harder to get pregnant as you age. This is true for anyone. If you didn't get the shot and your baby was RH positive there could be a problem.

I., mittlesmirz simply means pain at ovulation. This does not keep you from getting pregnant, it's your body signalling you that you are ovulating - ding ding ding, time to make a baby. Knowing when you are ovulating should make conception easier, not harder.
Many people have a negative blood type, it isn't a cause for illness, some people are A positive, some are A negative (same with B, AB and O blood types) but if your baby's father is rh+, you must speak with your doctor about Rhogam injections - future pregnancies can be at risk.

I'm not sure what the problem is - mittlesmirz means pain during ovulation (in the middle of your cycle). It is not an illness in itself. Being rH negative has nothing to do with your fertility or illness either. Care to elaborate?

Neither should be a problem at any point in your life.