30 weeks u/s measurements. bpd: 70mm, femur: 61mm, hc: 250 ac: 236, hl/bpd 0.7, humerus: 48.8. is this bad if so, to what extent

Measurements: Consult your OB gyn. This data is charted to assign a % rank for growth, as related to your dates. It will also calculate a "fetal weight". This data should be used with caution as 3rd trimester us is only accurate to within +/- 3 wks and +/- a pound (which is a huge margin of error for a 4lb fetus!) . This is only one factor of many to eval a pregnancy, so don't place too much emphasis on it.