70 is extreamly low and would be very rare to be normal in anyone, are you sure you are talking about platelets and not something else, like heamoglobin? 70 would be considered to be a moderate case of amaemia. As Beema said normal is between 150-400. Problems with low platlets would be increased risk of bleeding and briusing.
I have been to many specialists for my condition and yes I am talking about platelets. I know i am lower than normal. My point was that I am normally 70 (which is extremly low) however in pregnancy i went up to 112 and above.