how long should heaprin injections be given to a pregnant female who is in her 8 weeks of pregnancy. She already has had 15 doses of heparin. units .5cc low molecular wt heparin 0.3 mg. anti phospholipid anti body negative ANA negative. TSH 4.5.

she has been prescribed to take heparin till 8 th month of gestation along with asprin. the girl is 24 years old and had one abortion. US abd scan showed scanty ovarian tissue. can some one suggest any alternative treatment and aslo whether heaprin is safe for such a prolonged usage.?