Introduction

Chiari-Frommel syndrome, Sheehan syndrome, and pituitary adenomas are three different medical conditions that affect the pituitary gland, a small but powerful gland in the brain responsible for regulating key hormones involved in growth, stress, fertility, and metabolism. 

Chiari-Frommel syndrome typically occurs after childbirth and involves prolonged milk production and absent periods due to high prolactin levels.¹ Sheehan syndrome is caused by severe blood loss during or after delivery, which damages the pituitary gland and leads to low hormone levels.² Pituitary adenomas are benign tumours that may either produce too many hormones or press on nearby brain structures, causing symptoms such as headaches, vision problems, and menstrual irregularities.³ 

Understanding the differences between these conditions is essential to ensure accurate diagnosis and proper treatment. This article will explain the key differences between all three conditions, looking at their causes, symptoms, diagnosis, and treatment.

What is the pituitary gland?

The pituitary gland is a small, pea-sized gland located at the base of the brain, just behind the bridge of the nose. Despite its size, it plays a big role in controlling many of the body’s important functions. It’s often called the “master gland” because it releases hormones that tell other glands in the body what to do.⁴ The pituitary gland helps regulate:

• Growth
• Reproduction and menstrual cycles
• Milk production after childbirth
• Thyroid function
• Stress response

It does this by producing several hormones, including prolactin (which stimulates milk production), follicle-stimulating hormone (FSH) and luteinising hormone (LH) (which control reproductive hormones), adrenocorticotropic hormone (ACTH) (which stimulates the adrenal glands), thyroid-stimulating hormone (TSH) (which controls the thyroid), and growth hormone.⁵

Because the pituitary gland is responsible for so many body functions, damage or disruption, as seen in Chiari-Frommel syndrome, Sheehan syndrome, or pituitary adenomas, can lead to a wide range of symptoms. 

Chiari-frommel syndrome 

Chiari-Frommel syndrome usually develops after childbirth when the hormone prolactin remains too high for too long. In this condition, prolactin levels stay elevated even when the person is not breastfeeding, leading to ongoing milk flow (galactorrhoea) and missed periods (amenorrhoea). Other symptoms may include anxiety, headaches, abdominal pain, backaches, impaired vision and emotional distress. 

Although the exact cause is not fully understood, it is thought to involve a disruption in the normal hormonal feedback between the hypothalamus and the pituitary gland, which interferes with the body’s ability to regulate prolactin levels.¹

Sheehan syndrome 

Sheehan syndrome occurs when a person experiences severe blood loss during or shortly after childbirth. This significant loss of blood can reduce blood flow to the pituitary gland, which is particularly vulnerable during pregnancy because it enlarges and becomes more sensitive to changes in blood supply. 

When the gland doesn’t receive enough oxygen and nutrients, parts of it can die. As a result, the damaged pituitary gland is no longer able to produce enough of the hormones it normally releases. This condition is called hypopituitarism, and it can affect many of the body’s essential functions.^2,6

People with Sheehan syndrome may have difficulty producing breast milk after delivery  (agalactorrhoea), miss periods (amenorrhoea), and experience symptoms such as: ^2,6

• Extreme fatigue 
• Low blood pressure 
• Sensitivity to cold
• Weight gain
• Dry skin

These symptoms may appear soon after birth or develop slowly over months or even years, which can delay diagnosis.^2,6

Pituitary adenomas 

Pituitary adenomas are non-cancerous (benign) tumours that develop in the pituitary gland. Although these growths are not cancerous, they can still have a significant impact on health due to the important role the pituitary gland plays in regulating hormones that control growth, reproduction, stress, and metabolism.³

Some pituitary adenomas are known as functioning tumours, meaning they produce excess amounts of hormones. For example:⁷

• Prolactin-secreting tumours (prolactinomas) can cause missed periods, infertility, and unexpected milk production (galactorrhoea)
• Tumours that produce growth hormone may lead to a condition called acromegaly, where the hands, feet, and facial features become enlarged
• If the tumour makes ACTH, it can lead to Cushing’s disease, which causes symptoms such as weight gain, high blood pressure, and easy bruising

Other pituitary adenomas are non-functioning, meaning they don’t produce hormones themselves. However, they can still cause problems by growing large and pressing on nearby parts of the brain, especially the optic nerves, which can lead to headaches and vision problems, often affecting peripheral (side) vision.⁷

Diagnostic criteria

To make an accurate diagnosis, doctors don’t rely on just one test or symptom; they take a step-by-step approach that includes checking hormone levels through blood tests and using MRI scans to assess the structure of the pituitary gland. 

Blood tests

In these three conditions, doctors often check key hormone levels to look for clues, especially prolactin, FSH, LH, TSH, cortisol, and oestrogen. 

Imaging studies

Doctors often use magnetic resonance imaging (MRI) to look at the structure of the pituitary gland when a pituitary disorder is suspected. This scan helps confirm or rule out physical changes that could explain symptoms and abnormal hormone levels.

Chiari-frommel syndrome

In Chiari-Frommel syndrome, MRI findings are often normal, as it is usually a functional disorder without structural damage. However, in some cases, a small pituitary tumour (microadenoma) may be present, particularly if prolactin levels are very high. These tumours are usually too small to cause headaches or vision problems, but can still affect hormone regulation.¹

Sheehan syndrome

In Sheehan syndrome, the MRI may show that the pituitary gland is shrunken or missing, a finding known as an empty sella, which is seen in about 70% of cases. A partially empty sella appears in around 30%. In early stages, MRI may detect central pituitary infarction without bleeding, especially if the gland is enlarged during pregnancy. Over time, this can lead to pituitary atrophy.^2,8

Pituitary adenomas

In pituitary adenomas, MRI often reveals a clearly visible tumour. These may be microadenomas (less than 10 mm) or macroadenomas (more than 10 mm), and larger tumours may press on nearby structures such as the optic nerves, causing headaches or vision problems.^3,9

Treatment approaches

Chiari-frommel syndrome

Chiari-Frommel syndrome is usually treated with medication aimed at lowering prolactin levels, which are often too high after childbirth. Doctors commonly prescribe dopamine agonists such as bromocriptine.

These medications work by stimulating dopamine receptors in the brain, which helps reduce prolactin production. This can stop milk production and allow menstrual cycles to return. In most cases, medication alone is enough. However, if a prolactin-secreting tumour (such as a microadenoma) is found and does not respond well to medication, surgical removal may be considered.¹

Sheehan syndrome

Since Sheehan syndrome results from damage to the pituitary gland, the body can no longer make enough of several essential hormones. Treatment focuses on replacing what’s missing.

Lifelong hormone replacement therapy may include:

• Corticosteroids (e.g., hydrocortisone): to  replace cortisol
• Thyroxine: for thyroid hormone balance
• Oestrogen and progesterone: to manage menstrual health and support fertility
• Growth hormone: sometimes used, especially in younger patients

Patients need regular monitoring to adjust medication doses and prevent symptoms from returning.^2,6,8

Pituitary adenomas

Treatment depends on the size of the tumour and whether it is producing hormones. For hormone-producing tumours (e.g., prolactinomas), dopamine agonists are often effective. These medications can shrink the tumour and normalise hormone levels without surgery.^3,9

For larger or non-responsive tumours:^3,9

• Surgical removal is often recommended, especially if the tumour is:
  • Causing vision problems
  • Pressing on nearby brain structures
  • Not responding to medication
• The most common operation is transsphenoidal surgery, done through the nose and sinuses

Other treatments may include:^3,9

• Radiotherapy: if the tumour cannot be fully removed or grows back
• Hormone replacement therapy: if the tumour or surgery affects normal pituitary function 

Summary

• Chiari-Frommel syndrome, Sheehan syndrome, and pituitary adenomas are three conditions that affect the pituitary gland and can present with similar symptoms, like missed periods, milk production, and fatigue
• Chiari-Frommel syndrome is a postpartum condition caused by prolonged high prolactin levels and is usually treated with medication to restore hormone balance
• Sheehan syndrome results from severe blood loss during or after childbirth, which damages the pituitary gland and leads to multiple hormone deficiencies requiring lifelong replacement therapy
• Pituitary adenomas are benign tumours that may produce excess hormones or cause pressure-related symptoms, and are treated with medication, surgery, or radiotherapy, depending on their size and activity
• Diagnosis is based on clinical history, hormone blood tests, and MRI scans to identify hormonal imbalances or structural abnormalities
• Early and accurate diagnosis is essential for effective treatment and to reduce the risk of long-term complications