I am one year post partum. My last 2 periods have been heavier than usual with some thick, glob like chunks in the flow. What can cause this?

Many possibilities. If one notes a significant change in amount or character of menstrual bleeding that persists for 2 or more cycles, there can be several explanations. These can include endometrial polyps, uterine fibroids, ovarian cyst, and possibly adenomyosis. Some of these can be diagnosed with an examination and pelvic ultrasound, while others may require a procedure known as a hysteroscopy.