As per your horoscope 5th house is the weakest one which signify unhappiness on account of children. So is your sixth and seventh house. Sun, Venus is responsible for this. Read Srimad Maha Bhagavatam with devotion and perhaps you will get favours from the Lord Almighty. Here is the link http://srimadbhagavatam.org/contents.html
Needless to say you should take medical help since your uterus is not able to carry the weight of the baby.