Your little one has been home for a couple of weeks now, and they’re a beautiful bundle of joy. But unfortunately, you haven’t been feeling too well as of late. You’ve been losing weight, you struggle to sleep, you get hot and sweaty very easily and you often feel anxious. So you have a call with your doctor and ask them what they think might be going on. And after explaining your symptoms, they tell you that they think it might be hyperthyroidism.

But what is hyperthyroidism?

Hyperthyroidism is a condition that sees the thyroid gland produce too much of the thyroid hormone, causing weight loss, insomnia, tremors, anxiety, heat rushes and sweats, and a rapid heartbeat, amongst other things. Some mothers develop postpartum thyroiditis – mild hyperthyroidism experienced in the months after the birth of their baby. But while it’s still important to speak to your doctor, postpartum thyroiditis typically resolves itself within a few weeks and so won’t necessarily require treatment.

That being said, if you were being treated for a hyperthyroid condition or Graves disease before pregnancy, or if your symptoms are severe and long-lasting, you’ll need to see your doctor so as to gain a proper diagnosis and form a plan of treatment.

But how will you know if you have hyperthyroidism?

How is hyperthyroidism diagnosed?

There are a number of different ways to diagnose hyperthyroidism, the most common of which include blood tests, ultrasounds or a needle biopsy of the thyroid. And thankfully, all are safe for both you and your baby. However, one diagnostic technique, known as a thyroid scan, involves the use of radioactive iodine. If your doctor wishes to conduct a thyroid scan it’s important that you keep from breastfeeding your baby for 48 hours, because the iodine in your system will prove unsafe for your tiny tot. During those 48 hours, feed them formula or pre-expressed breast milk that's been kept in the fridge or freezer, and then pump and dump your breast milk. That way your breasts won’t become engorged and you’ll keep up your milk supply.

So, let’s say you’ve received a diagnosis of hyperthyroidism. You’ll likely be asking, will I still be able to breastfeed my baby?

How can I breastfeed with hyperthyroidism?

Very rarely will a breastfeeding mother diagnosed with hyperthyroidism have to completely abandon breastfeeding. So long as you’re regularly seeing your doctor and you follow the treatment plan they set out for you (which will most likely involve taking medication), you can keep on breastfeeding your little one.

But there are a few things you’ll need to be aware of and keep in mind:

Radioactive iodine is sometimes used to treat hyperthyroidism. If this happens to be the case, and you want to continue breastfeeding, you’ll have to pump and dump in the meantime. But be aware that it can take months for the iodine to leave your body, so speak to your doctor and find out if another treatment might suit you better.

While most of the medication your doctor will prescribe is safe for your baby, it’s still best to time your doses so that you’re nursing beforehand.

Stress and smoking can make symptoms worse, so while it’s easier said than done, try to avoid both wherever possible.

In some rare cases, a doctor may feel that it's necessary to remove some or all of your thyroid. But once the procedure, known as a thyroidectomy, is over and you feel you’re able, you can begin to breastfeed again.

Hyperthyroidism can sometimes increase your milk production to the extent that there’s more milk than your baby will take in, and this can then lead to breast engorgement. Pumping and storing excess milk and wearing nursing bras or cooling gel breast pads can help to reduce swelling and discomfort.

Can I breastfeed with an overactive thyroid?