Honestly, I haven't heard of any major issue with ginger shampoo during pregnancy, but since it's something that goes on your scalp and you're absorbing it, best to check with your OB muna to be safe, preggy kasi talaga, mas careful tayo sa lahat, diba? A few of my mum friends just stuck to their regular mild shampoos during pregnancy para walang hassle, pero bawat preggy rin is different, so what worked for them might not be the same sa'yo. Better safe than sorry, mamsh!