Yes, slate pencil is harmful for everyone not just during pregnancy. This means you are having Deficiency of minerals like Ca And Mg.
So, try to get out of it. And have healthy diet.
If you want to know more ou can contact me through the link below
Next Steps
For more information and to contact me directly visit https://www.facebook.com/pg/doctorplanmydiet/about/
Thanks with regards
Dt.Ankita