**Core Concept**
In the postpartum period, women with pre-existing cardiac conditions require careful contraceptive planning to avoid exacerbating their condition. The choice of contraceptive method should take into account the patient's cardiac status, potential interactions with medications, and the need for effective contraception.

**Why the Correct Answer is Right**
For a P2L2 (postpartum, second live birth) poorly compensated cardiac patient, the preferred contraceptive method is the **progestin-only pill (POP)**, also known as the mini-pill. This is because POPs are safer in patients with a history of thromboembolic events or those on anticoagulant therapy, as they do not affect blood clotting as much as combined oral contraceptives (COCs) do. Additionally, POPs are a good option for breastfeeding mothers, as they do not affect milk production.

**Why Each Wrong Option is Incorrect**
**Option A:** Combined oral contraceptives (COCs) are not recommended for patients with a history of thromboembolic events or those on anticoagulant therapy, as they increase the risk of blood clots.

**Option B:** Intrauterine devices (IUDs) are not an ideal choice for postpartum patients, as they can increase the risk of infection and may not be effective until several weeks after delivery.

**Option C:** Depot medroxyprogesterone acetate (DMPA) injections are not recommended for patients with a history of thromboembolic events, as they can increase the risk of blood clots.

**Clinical Pearl / High-Yield Fact**
When choosing a contraceptive method for a postpartum patient with a pre-existing cardiac condition, consider the patient's medical history, current medications, and the need for effective contraception. Always select the safest and most effective option to minimize the risk of adverse outcomes.

**Correct Answer:** C. Depot medroxyprogesterone acetate (DMPA) injections are not recommended for patients with a history of thromboembolic events, as they can increase the risk of blood clots.