Repeated Pre reqs Help : Personal Statement

My school never had this but whenever I did retake pre-reqs it was always due to stress or classroom environment.

I had a repeat because I had to move to another town due to my pregnancy being very difficult and needing additional support. 
 

I wish the schools I applied to had this generous offer, to explain! One school subtracted 2 points from my application for having a W in Microbiology.

Is there a word limit? I would try to keep it short. Maybe half a page or 3/4 of a page. Admissions offices have to go through a lot of applications, so I am sure they would appreciate students who are concise. The statement should start out explaining what hardships you suffered that caused you to have to retake the prerequisites and then end with you discussing what you learned from the experience and how it has made you a better student/person.