15 weeks pregnant and bleach smell in panties. no abnormal amount of discharge.

Bacterial vaginosis?: The main cause of strong vaginal odor is bacterial vaginosis, overgrowth of mostly normal bacteria. Discharge can be slight or none at all. The odor is typically described as fishy, but odor is very subjective, and "bleach" may be the same. If it continues, discuss with your obstetrician. It will be quick and easy to see if anything is wrong and, if necessary, prescribe treatment. Good luck!