Sheehan syndrome is a condition that happens when the pituitary gland is damaged during childbirth. It’s caused by excess blood loss (hemorrhage) or extremely low blood pressure during or after labor. A lack of blood deprives the pituitary of the oxygen it needs to work properly.

The pituitary gland sits at the base of the brain. It produces hormones that oversee the function of your body’s other glands. That’s why it’s nicknamed “the master gland.” This gland is more vulnerable to injury in labor, because it grows bigger during pregnancy.

When the pituitary doesn’t work as well as it should, the glands it controls — including the thyroid and adrenal glands — can’t release enough of their hormones. Sheehan syndrome affects production of these pituitary hormones:

  • Thyroid-stimulating hormone (TSH) directs your thyroid gland to produce its hormones, which regulate your metabolism.
  • Luteinizing hormone (LH) helps regulate your menstrual cycle and egg production, together with FSH.
  • Follicle-stimulating hormone (FSH) helps regulate your menstrual cycle and egg production, together with LH.
  • Growth hormone (GH) controls organ and tissue growth.
  • Adrenocorticotropic hormone (ACTH) stimulates your adrenal glands to release cortisol and other stress hormones.
  • Prolactin stimulates milk production.

Sheehan syndrome is also called postpartum hypopituitarism.

The symptoms of Sheehan syndrome sometimes start right after childbirth. Or, they can come on gradually months or even years later. Women who have very little damage to their pituitary gland might not develop symptoms for several years.

Symptoms of Sheehan syndrome include:

  • difficulty breastfeeding or an inability to breastfeed
  • irregular menstrual periods (oligomenorrhea) or no periods (amenorrhea)
  • weight gain
  • intolerance to cold
  • slowed mental function
  • loss of pubic and underarm hair
  • fatigue or weakness
  • fine wrinkles around the eyes and lips
  • breast shrinkage
  • dry skin
  • joint pain
  • decreased sex drive
  • low blood sugar
  • low blood pressure
  • irregular heartbeat

A lack of oxygen to the pituitary gland during childbirth causes Sheehan syndrome. Excess blood loss or very low blood pressure in labor can deprive the pituitary of the oxygen it needs to function.

Sheehan syndrome is most common in developing nations like India. Today it’s rare in the United States and other developed nations, thanks to better medical care during delivery.

Factors that make you more likely to have severe blood loss include:

  • placental abruption, when the placenta that nourishes the unborn baby detaches from the uterus
  • placenta previa, when the placenta partly or totally covers the cervix (the bottom part of the uterus that connects to the vagina)
  • giving birth to a large baby, who weighs more than 8.8 pounds (4,000 grams), or having multiples, like twins
  • preeclampsia, high blood pressure during pregnancy
  • assisted labor, a forceps or vacuum-assisted delivery

Sheehan syndrome can easily be confused with other conditions that cause similar symptoms — especially if the symptoms don’t start for many months after you deliver.

Your doctor will start by asking about your symptoms. Your memory of related symptoms — like trouble producing breast milk after delivery — will help your doctor diagnose you.

Tests that help your doctor diagnose Sheehan syndrome include:

  • Blood tests. You’ll have tests to check levels of hormones that your pituitary gland makes. The pituitary hormone stimulation test checks how well your pituitary gland responds to different hormones.
  • Magnetic resonance imaging (MRI) or computed tomography (CT) scans. These imaging tests check for tumors or other problems with your pituitary gland that can cause similar symptoms.

Treatment for Sheehan syndrome is to take the hormones your body no longer produces. You’ll need to stay on most of these hormones for life:

  • Corticosteroids. Prednisone or hydrocortisone replaces adrenal hormones.
  • Levothyroxine (Levoxyl, Synthroid). This medication increases the levels of the hormones your thyroid gland makes.
  • Estrogen plus progesterone (or estrogen alone, if your uterus has been removed). These female hormones help normalize your menstrual cycle. You can stop taking them once you reach the age of menopause.
  • LH and FSH. These hormones stimulate ovulation and can help you get pregnant.
  • Growth hormone. This hormone helps maintain bone density, improves your body’s ratio of muscle to fat, and lowers cholesterol levels.

A specialist called an endocrinologist will oversee your treatment. You’ll have regular blood tests to check your hormone levels.

Can it be prevented?

Good medical care during childbirth can prevent severe bleeding and low blood pressure. Once severe bleeding happens, Sheehan syndrome isn’t preventable.

Complications of Sheehan syndrome include:

  • adrenal crisis, a life-threatening condition in which your adrenal glands don’t produce enough of the stress hormone, cortisol
  • low blood pressure
  • unexpected weight loss
  • irregular periods

Sheehan syndrome can be life-threatening if you don’t get treated. With long-term hormone therapy, you should be able to live a healthy, normal life.