Type of Pituitary apoplexy (infarction or haemorrhage of pituitary gland)
The specific association with postpartum shock or haemorrhage was described in 1937 by the British pathologist Harold Leeming Sheehan (1900–1988). The initial distinction was made in the research article “Post-Partum Necrosis of the Anterior Pituitary”. In his research, Dr Sheehan reviewed (through autopsy) the effects of pituitary necrosis on 12 cases of patient’s that experienced postpartum necrosis. He observed cases where lesions and death occurred during or after pregnancy, as well as cases where death occurred in the late stage of necrosis (years later). This started the initial distinction of Sheehan’s syndrome from Simmonds’ disease (also known as hypopituitarism). Dr Sheehan noted that significant features of these patient cases were haemorrhaging, which in his experience was most commonly caused by either: placenta Previa (low placenta), uterine rupture, cervical or uterine tears, post-partum atony, or retained placenta. Simmonds’ disease, however, occurs in either sex due to causes unrelated to pregnancy.
However, in his 1939 publication: “Simmonds’ Disease due to Post-partum Necrosis of the Anterior Pituitary”, Dr Sheehan displays post-partum necrosis as a cause of Simmonds’ disease, thus establishing the relationship between the two conditions. According to Sheehan in 1939 approximately 41% of survivors of severe postpartum haemorrhage (PPH) and/or hypovolemic shock experienced severe or partial hypopituitarism.
Small sella turcica
Anatomy of pituitary gland:
Adenohypophyseal ischaemic necrosis following hypoperfusion
At least 75% of pituitary must be destroyed before clinical manifestations become evident.
Prolactin and growth hormone: M/C hormones affected by selective pituitary necrosis and hypofunction
Characteristic manifestations include failure to lactate or to resume menses, genital and axillary hair loss, asthenia and weakness, fine wrinkles around the eyes and lips, signs of premature aging, dry skin, hypopigmentation and other evidence of hypopituitarism.
Usually present in the postpartum period with lactation failure or after many months to years following the inciting delivery.
Agalactorrhoea (lack of prolactin) or amenorrhoea (lack of LH & FSH)
Lack of growth hormone:
Asthenia and weakness
Dry skin, hypopigmentation
Signs of premature ageing
Genital and axillary hair loss
Fine wrinkles around the eyes and lips
2° Adrenal insufficiency:
Pituitary hormone levels:
Pituitary ring sign: Ring enhancement or halo around sella turcica
Aggressive management of PPH & other causes of blood loss