I M 27 Weeks Pregnant And Have Been Diagnosed With

I m 27 weeks pregnant and have been diagnosed with two vessel cord(single umblical artery) but all fetal measurements are in the normal range.fetal heart rate is 138 and weight is 1060 gm. Placenta is posterior wall upper utrine segment with grade 2 maturity. Is my baby growing normal and healthy.i am very nervous and concerned about this two vessel cord..please advise..