Correct Answer: D. Uterine artery – Ovarian artery – Internal iliac artery
The stepwise ligation of uterine blood vessels in atonic postpartum hemorrhage follows a proximal-to-distal approach, progressing from the primary source of bleeding to increasingly proximal vessels. The uterine artery is ligated first because it is the primary direct blood supply to the uterus and accounts for the majority of uterine perfusion; this is the most effective initial intervention. If bleeding persists, the ovarian artery (which arises from the abdominal aorta and anastomoses with the uterine artery via the ovarian branch of the uterine artery) is ligated next to cut off collateral supply. Finally, if hemorrhage continues despite these ligations, the internal iliac artery (anterior division) is ligated as the ultimate proximal vessel—this is the parent trunk supplying both uterine and vaginal arteries and represents the final hemostatic measure. This stepwise approach preserves ovarian function and fertility when possible while ensuring complete hemostasis. The internal iliac ligation is the last resort because it sacrifices more distal structures but provides the most reliable control of pelvic hemorrhage. This sequence aligns with the principle of selective vascular ligation taught in Indian obstetric training (AIIMS, PGIMER protocols) and is the standard of care before resorting to hysterectomy.
Why the other options are wrong
A. Uterine artery – pudendal artery – Vaginal artery — This is incorrect because the pudendal artery does not supply the uterus; it supplies the external genitalia and perineum. The pudendal artery is a branch of the internal pudendal artery (from internal iliac) and is not part of the uterine vascular cascade. This option confuses perineal bleeding control with uterine hemorrhage management. B. Uterine artery – Ovarian artery – Vaginal artery — While the first two vessels are correct, the vaginal artery is too distal and minor a vessel to be the final step in controlling massive postpartum hemorrhage. The vaginal artery is a small branch of the internal iliac and does not provide sufficient hemostatic control when uterine and ovarian ligations fail. The internal iliac artery (the parent trunk) must be ligated instead for definitive control. C. Uterine artery – Ovarian artery – External iliac artery — The external iliac artery is incorrect as the final vessel because it does not supply the uterus or pelvic organs; it is the continuation of the common iliac artery and supplies the lower limb. Ligating the external iliac would cause limb ischemia without controlling pelvic hemorrhage. The internal iliac (anterior division) is the correct proximal vessel.
High-Yield Facts
- Uterine artery ligation is the first-line vessel ligation in atonic postpartum hemorrhage; it supplies 90% of uterine blood flow.
- Ovarian artery (from abdominal aorta) provides collateral supply via anastomosis with the uterine artery and must be ligated if uterine ligation fails.
- Internal iliac artery ligation (anterior division) is the final hemostatic measure; it is the parent trunk of uterine, vaginal, and other pelvic vessels.
- The stepwise ligation sequence preserves ovarian function and fertility compared to hysterectomy, which is reserved for uncontrolled hemorrhage.
- Uterine artery arises from the anterior division of the internal iliac artery at the level of the internal cervical os.
Mnemonics
UOI – Uterine Ovarian Internal iliac Remember the stepwise ligation order: Uterine → Ovarian → Internal iliac. This reflects distal-to-proximal progression, preserving fertility at each step before resorting to the final proximal ligation. Proximal Progression Rule Start at the bleeding site (uterus), then move to collateral sources (ovarian), then to the parent trunk (internal iliac). Each step is more proximal and more effective if the previous step fails.
NBE Trap
NBE may lure students into choosing the vaginal artery (option B) by pairing it with the correct uterine and ovarian arteries, making it seem like a complete distal-to-proximal sequence. However, the vaginal artery is too minor and distal to provide definitive hemostasis when major uterine and ovarian ligations fail; the internal iliac artery (the actual parent trunk) must be the final step.
Clinical Pearl
In Indian tertiary centres (AIIMS, PGIMER), the uterine artery ligation is performed first via a transverse lower segment incision or laparotomy, with the vessel identified just lateral to the uterus at the level of the internal cervical os. If bleeding persists despite this, ovarian artery ligation is added, and only if hemorrhage remains uncontrolled is internal iliac ligation considered—this stepwise approach has reduced hysterectomy rates in resource-limited settings where blood products may be scarce.
_Reference: DC Dutta's Textbook of Obstetrics (7th ed.), Ch. 22 (Postpartum Hemorrhage); Bailey & Love's Short Practice of Surgery, Ch. 71 (Obstetric Surgery)_