A 27-year-old woman who had massive postpartum hemorrhage requiring transfusion now reports inability to breastfeed her newborn despite normal mammary development, along with persistent amenorrhea and fatigue. MRI of the sella shows a partially empty sella. The earliest hormonal deficit responsible for the lactation failure involves:

• A Prolactin ✓
• B ACTH
• C Growth hormone
• D TSH

Explanation

Sheehan syndrome is postpartum pituitary necrosis caused by ischemia of the physiologically enlarged gland during obstetric hemorrhage. Lactation failure results from loss of prolactin, and prolactin together with growth hormone is among the first hormones lost because somatotrophs and lactotrophs are the most vulnerable cell populations. Corticotroph deficiency tends to appear later, which is why adrenal crisis is typically delayed rather than immediate.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.