Over the last 10 years, the prevalence of major postpartum haemorrhage (PPH), defined as over 1000 ml (Mavrides et al, 2016), has increased greatly. An audit of three independent UK units showed increases in PPH rates (> 1000 ml) of over 500% in the period 2003–2013 (Oberg et al, 2014). It has been estimated that a major PPH (> 2500 ml) affects 0.6% of all births (Lennox and Marr, 2013).
Midwives and obstetricians have become adept at identifying and managing major obstetric haemorrhages. The commonly associated morbidity with major PPHs is well documented, and includes multiple transfusions, invasive surgery, intensive care unit admission, acute kidney injury and post-traumatic stress. However, many midwives are not aware of the potential complication of Sheehan's syndrome following a PPH.
Sheehan's syndrome—also known as Simmond's syndrome—is partial or complete pituitary failure in the postpartum period. It is a rare complication of pregnancy, estimated to affect 1/10 000 pregnancies (GPnotebook, 2017). Ninety per cent of cases are seen following a PPH with associated hypotension (Nelson-Piercy, 2015). It is thought that the pituitary gland is particularly susceptible to postpartum necrosis, predominantly owing to its increased in size in pregnancy to facilitate breastfeeding without an increase in its blood supply. Following a major PPH, there can be systemic hypotension resulting in a reduced blood supply to the pituitary gland from acute blood loss. Sheehan's has also been seen following disseminated intravascular coagulation and amniotic fluid embolism. British pathologist Harold Leeming Sheehan first described Sheehan's syndrome in 1937, whereas Simmond's syndrome can occur in either sex, completely unrelated to pregnancy complications.
Common clinical features of Sheehan's syndrome (Nelson-Piercy, 2015) include:
Sometimes it can take years before Sheehan's syndrome is diagnosed. However, it can uncommonly present acutely following birth with hyponatraemia (Schrager and Sabo, 2001) resulting in seizures and confusion post-delivery.
Midwives may often be the first health professional to whom a woman may report difficulty in lactation. Of course, tiredness and breastfeeding problems are common in the postnatal period, so do not necessarily indicate Sheehan's syndrome, which is extremely rare. However, it is important to be aware of the signs, and midwives should refer women to an obstetrician for further evaluation if they are concerned.
Most cases of Sheehan's syndrome are successfully treated with hormone replacement therapy.