How do i get rid of dark marks on my skin safely and quickly,no surgeries?i survived steven johnson syndrome.?

i miraculously survived steven johnson syndrome abt6 years ago and have had severe marks all over.they wer gradualy fading,no harmful chemicals or surgeries involved.but nw im expectng my 1st child next month and the pregnancy darkened the marks again.im a woman of colour.i nid help for after i deliver what can i use to permanently fade away thz marks.they r al over my body head to toe and its so bad i dnt wear shorts or sleeveles tops.i react to many chemicals so smthn natural wd b rly apreciated.please help im desperate.