In a case of twin pregnancy, the risk of postpartum hemorrhage (PPH) is highest due to which underlying cause?

JIPMER Nursing Officer-2024

Obstetrics & Gynaecology

Medium

Appeared in: JIPMER Nursing Officer-2024

Explanation

A twin pregnancy is a major risk factor for uterine atony because it causes significant overdistension of the myometrium (uterine muscle).
This overstretching compromises the muscle fibers' ability to contract and retract effectively after the delivery of the placentas.
Effective uterine contraction is the primary mechanism for controlling bleeding from the placental implantation site by compressing the spiral arteries.
Failure of the uterus to contract (atony) is the leading cause of primary postpartum hemorrhage (PPH), accounting for approximately 80% of cases.
Therefore, in the context of a twin pregnancy, the physiological consequence of overdistension makes atonic uterus the highest risk for PPH.

Option A: Placenta previa, where the placenta implants low in the uterus, is a major cause of antepartum (before delivery) hemorrhage, not the primary cause of postpartum hemorrhage related to uterine overdistension.
Option C: Abruptio placentae is the premature separation of the placenta. While it can cause severe bleeding and may lead to coagulopathy (a 'Thrombin' issue), it is an acute placental complication, not a direct result of the uterine overdistension characteristic of a twin pregnancy.
Option D: Retained placenta is a cause of PPH (classified under 'Tissue' in the 4 T's), where placental fragments prevent the uterus from contracting fully. However, uterine atony ('Tone') is a much more common cause of PPH, especially in the setting of an overdistended uterus from a twin pregnancy.

Visual 1: Diagram - A comparison showing a well-contracted, firm postpartum uterus versus a large, boggy, atonic uterus. This helps visualize the mechanical failure in uterine atony.
Visual 2: Infographic - A chart illustrating the 'Four T's of PPH' (Tone, Tissue, Trauma, Thrombin) with representative icons and percentages for each cause, highlighting that 'Tone' is responsible for 80% of cases.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Etiology of Postpartum Hemorrhage in Multiple Gestation as background academic context rather than a clinical decision trigger.
Nurses must anticipate a high risk of PPH in patients with multiple gestations. Proactive management includes ensuring IV access, availability of cross-matched blood, and having uterotonic drugs readily available at delivery.
The primary nursing intervention for a boggy, atonic uterus is immediate and vigorous fundal massage to stimulate contraction, while simultaneously calling for help and initiating the PPH protocol.
What if? - If fundal massage and initial oxytocin administration fail to control bleeding from an atonic uterus, the nurse should anticipate the administration of second-line uterotonics like carboprost (Hemabate), methylergonovine (Methergine), or misoprostol (Cytotec), and prepare the patient for potential escalation to procedures like balloon tamponade or surgical intervention.

How to Approach the Question

First, identify the key elements in the question: 'twin pregnancy' and 'highest risk' for 'postpartum hemorrhage (PPH)'.
Recognize that 'twin pregnancy' is a condition that leads to uterine overdistension.
Think about the normal physiological process that stops bleeding after delivery: uterine contraction (involution) compressing blood vessels.
Connect uterine overdistension to a potential failure of this process. Overstretched muscles have a harder time contracting effectively.
Evaluate the options based on this physiological link. 'Atonic uterus' directly describes the failure of the overstretched uterine muscle to contract.
Consider the other options: Placenta previa is an antepartum issue. Abruptio placentae is a placental separation issue. Retained placenta is a possible cause, but atony is the most direct and common consequence of overdistension.

Concept Tested & Keywords

Concept Tested: Etiology of Postpartum Hemorrhage in Multiple Gestation
Stem keywords: twin pregnancy, postpartum hemorrhage, PPH, highest risk, underlying cause
Lead-in keywords: highest due to
Clinical cues: The key clinical detail is 'twin pregnancy', which points towards uterine overdistension as a primary factor.

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