Bfp on 10dpo, doubling hcg on 12dpo, but pink spotting today 16 dpo

Progesterone suppositories supplement any progesterone in your body bringing levels back to normal. It normalizes the endometrium (lining of the womb) by causing shedding of the excess layers that are built up by unbalanced estrogen. This shedding appears as spotting or what is known as breakthrough bleeding which may resemble a light period. Many women experience this as a side-effect of progesterone suppositories. There is no cause for alarm. The spotting usually subsides within 2-3 cycles.