AST, ALT, GGT, Bile acids.
A clinical examination to rule out signs of liver disease should be done, and additional tests ordered if any clinical abnormalities are found.
ALP- Is raised in pregnancy because of production by placenta. Should be considered abnormal only if it is above 400 U/L in pregnancy.
Of GGT, ALT and AST , only one may be raised at the initial raised Bile Acid Level .  ALT , AST and GGT may be raised in 50%, 37% and 13 % of women at the initial raised bile acid level.
Serum Bilirubin is usually normal.
Bile acid elevation in pregnancy is diagnostic and may have prognostic value in Intrahepatic cholestasis of pregnancy.
Ideally Bile acids should be checked in fasting state but in most settings, they are not tested in fasting state.
If initial labs are normal and the symptoms persist- LFT and bile acids should be checked after one week.