very good and i wish that all the gyanacology doctors must do the blood group and RH test first to see if the Rh is negative or not before requesting for the indirect coomb's test ( rh antibody test) becouse as you said if the rh is positive no need to do the test and this is a waste of money for the pregnant female ...the test must be done for the pregnant female with rh negative in the blood test may be repeated between 24
and 28 weeks of pregnancy. If the test still shows that you are not sensitized,
you probably will not need another antibody test until delivery. (You might
need to have the test again if you have an amniocentesis, if your pregnancy
goes beyond 40 weeks
titer less than 1:16 is considered insignficant