**Core Concept**
Atonic postpartum hemorrhage (PPH) refers to excessive bleeding due to uterine atony, which is the failure of the uterus to contract effectively after delivery. This condition is a leading cause of maternal morbidity and mortality worldwide. Uterine atony can be caused by various factors, including hormonal imbalances, uterine trauma, and underlying medical conditions.

**Why the Correct Answer is Right**
Preeclampsia is a pregnancy complication characterized by high blood pressure and often accompanied by significant amounts of protein in the urine. While preeclampsia can lead to various complications, including placental abruption and fetal growth restriction, it is not typically associated with uterine atony. In fact, preeclampsia is more commonly linked to placental insufficiency and maternal hypertension, which can lead to preterm labor and delivery. The uterine muscle tone in preeclamptic patients is often normal or even hypertonic, making atonic PPH an unlikely complication.

**Why Each Wrong Option is Incorrect**
**Option A:** Fibroids can cause atonic PPH by distorting the uterine cavity and disrupting normal uterine contractions. The presence of fibroids can lead to uterine atony, especially in cases where the fibroids are large or multiple.

**Option B:** Multiple pregnancy increases the risk of atonic PPH due to the increased uterine distension and the potential for uterine muscle fatigue. The larger uterine size and increased blood volume associated with multiple gestations can compromise uterine contractility.

**Option C:** Multiparity, or having given birth multiple times, is a known risk factor for atonic PPH. Repeated uterine distension and stretching of the uterine muscles can lead to muscle fatigue and decreased contractility, increasing the risk of atonic PPH.

**Clinical Pearl / High-Yield Fact**
A key factor to remember when managing atonic PPH is the importance of uterotonic agents, such as oxytocin and methylergonovine, to stimulate uterine contractions and control bleeding. Administering these agents promptly and in adequate doses can significantly reduce the risk of maternal morbidity and mortality.

**✓ Correct Answer: D. Preeclamptic**