I think that it’s a fantastic idea to supplement your liver and digestion to prepare for future pregnancies! It just depends on how you do it. A lot of herbs are controversial/contraindicated for pregnancy/lactating moms.
If you are just supporting your liver to do what it should be already doing, that would be ideal. I wouldn’t recommend pushing detox though.
So B vitamins, glutathione, making sure you’re digesting your proteins properly (HCl), coffee enemas (for lactating moms, not pregnant moms), phosphatidylcholine, beets/Beta TCP, etc. are all great options.