**Core Concept**
Oestrogen therapy can cause a temporary increase in the number of clotting factors and antithrombin III, leading to a hypercoagulable state. This is known as the "oestrogen effect" on coagulation. Withdrawal of oestrogen can lead to a decrease in these clotting factors, potentially resulting in bleeding.

**Why the Correct Answer is Right**
The correct answer is related to the concept of estrogen's effect on coagulation. Estrogen increases the production of clotting factors, such as Factor VII, Factor VIII, Factor IX, and Factor X, and antithrombin III, which are proteins involved in the coagulation cascade. When estrogen is withdrawn, the levels of these clotting factors decrease, leading to a state of hypocoagulability. This can manifest as bleeding or bruising after withdrawal of estrogen.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not relevant to the context of estrogen's effect on coagulation and bleeding.
* **Option B:** This option is incorrect because it does not directly relate to the concept of estrogen's effect on coagulation and bleeding.
* **Option C:** This option is incorrect because it is not a direct consequence of estrogen withdrawal.

**Clinical Pearl / High-Yield Fact**
When managing patients on estrogen therapy, it is essential to consider the potential effects of estrogen withdrawal on coagulation, particularly in patients with a history of bleeding disorders or those taking anticoagulant medications.

**Correct Answer:** D.