**Core Concept**
The underlying concept here is the management of recurrent thromboembolism in pregnancy, specifically the use of anticoagulants to prevent recurrence in a high-risk patient.

**Why the Correct Answer is Right**
The correct answer involves the use of warfarin as a form of anticoagulation to prevent recurrent thromboembolism in a patient with a history of puerperal embolism. Warfarin is a vitamin K antagonist that inhibits the synthesis of vitamin K-dependent clotting factors, thereby reducing the risk of thrombosis. In the context of pregnancy, warfarin is typically started after delivery, when the risk of bleeding is lower, to minimize the risk of fetal complications. This approach is particularly relevant in patients with a history of recurrent thromboembolism, as they are at increased risk of another event during the next pregnancy.

**Why Each Wrong Option is Incorrect**
**Option A:** Compulsory prophylaxis with warfarin starting at 10 weeks is incorrect because it does not take into account the risk of warfarin-induced fetal complications, such as warfarin embryopathy or fetal bleeding, which can occur during the first trimester. Warfarin is typically avoided during the first trimester of pregnancy.

**Option B:** This option is not explicitly incorrect, as it is the correct answer. However, we will address the other options to provide a comprehensive explanation.

**Option C:** The chance of thromboembolism increasing by 12% in the next pregnancy is not a specific recommendation or management strategy, but rather a general statement. While it is true that the risk of thromboembolism is increased in patients with a history of recurrent events, this option does not provide any guidance on how to manage the patient.

**Option D:** This option is incorrect because it suggests that no additional measures are necessary to prevent recurrent thromboembolism in a patient with a history of puerperal embolism. In reality, patients with a history of recurrent thromboembolism require ongoing management and prophylaxis to minimize the risk of another event.

**Clinical Pearl / High-Yield Fact**
In patients with a history of recurrent thromboembolism, it is essential to balance the risk of thrombosis against the risk of bleeding when selecting an anticoagulant. Warfarin is often used as a form of anticoagulation in these patients, but it must be carefully managed to minimize the risk of fetal complications.

**✓ Correct Answer: B. To take warfarin after delivery**