Brief Answer:
No problem because you (future mother)are positive

Detailed Answer:
Hi XXXXXXX,
Thanks for writing in to us.

I have read through your query in detail.
The positive and negative part of blood group is decided by the presence of a protein on their red blood cells called D antigen. If the man is A -ve (negative) then he does not have the D antigen. Since you are O +ve (positive) you have the D antigen in your red blood cells.

The absence of D antigen in him and its presence in you will not cause any problems in your child if you both marry each other and have a child.

Only when an Rh negative mother has a baby that is Rh positive, problems can develop if the baby's red blood cells cross to the Rh negative mother. This usually happens at delivery when the placenta detaches. It may also happen, however, anytime blood cells of the two circulations mix such as during a miscarriage or abortion, with a fall, or during an invasive prenatal testing procedure such as an amniocentesis or chorionic villus sampling.

Blood group problems only take place when mother is negative and baby is positive. This will not happen to you because you are positive.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

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