28 weeks pregnant with thick whitish yellowish discharge with a little pink in it. what could it be?

Discharge: could be a yeast infection since it is thick. If you've had intercourse recently the pink (blood) would be a common thing to happen. Since the weekend is almost here though I would call your OB either tonight thru the answering service (usually calling the office after hours gets the service) or first thing in the morning to discuss it further.

Needs testing: Vaginal discharge requires an examination to determine the cause and treatment. Bacterial vaginosis is the most common cause and often has a vaginal odor. Vaginal itching can be a sign of a yeast infection. Sometimes vaginal discharge can be a sign of a sexual transmitted infection. Testing is important to determine the treatment and keep you and your partner safe.