I Am Currently 27 Weeks Pregnant And Am High Risk

i am currently 27 weeks pregnant and am high risk due to previous iugr babies at moment baby growth fine as its early days however doc dont seem to think i will be allowed to pass 36 weeks just wondering why really as all looks good and i am taking aspirin this time round also my placenta on back wall feeding down last pregnancy it was feeding wrong direction and i was induced at 35 weeks is it possible i may go further than they are saying thanks maria