What is oxytocin?

Oxytocin is a hormone that's made in your brain. It's stored and released into your blood by your pituitary gland.

When oxytocin is released, it stimulates your pituitary gland to release even more.

During labour, oxytocin is released. This makes your uterus contract and more oxytocin is released. This increases the frequency and intensity of your contractions so that labour can progress.

What is the role of oxytocin?

Oxytocin plays a key role in causing uterine contractions during labour and birth. It also raises your levels of prostaglandins that also increase your contractions.

It's also involved in making and releasing milk from your breasts, so that you can breastfeed.

In males, oxytocin plays a role in sperm transport and making testosterone in the testes. It also has a role in penis erections and ejaculation.

Oxytocin also acts as a chemical messenger in your brain and influences human behaviour, such as:

• sexual arousal
• allowing people to recognise each other
• promoting trust
• building relationships and romantic attachment
• promoting bonding with your child

Oxytocin can decrease anxiety and stress.

How is oxytocin measured?

Researchers are trying to work out how best to measure our levels of oxytocin.

What happens if I have too much oxytocin?

Researchers are trying to understand how oxytocin affects your body.

It's thought that too much oxytocin could lead to benign prostatic hypertrophy (BPH) in males. This is a common condition of the prostate gland. It makes it difficult to urinate (wee).

In females, too much oxytocin can increase the muscle in your uterus.

What happens if I have too little oxytocin?

Low levels of oxytocin can:

• stop your uterus contracting during birth
• slow or stop your milk flow after your baby is born

It's also been linked to postnatal depression.

Low oxytocin levels have also been linked with autism spectrum disorder (ASD). Researchers are looking at whether oxytocin can help treat social functioning.

How can I adjust my oxytocin levels?

Research has shown that oxytocin levels increase naturally with pleasurable activities, for example:

• exercising
• music — such as singing in a group
• patting a dog
• physical touch, such as cuddling or a massage

How is oxytocin used as a medicine?

Oxytocin can be used as a medicine in some situations.

Oxytocin can be given via a drip to induce (start) or strengthen your contractions during labour.

It's also used to help:

• you deliver your placenta
• your uterus contract after childbirth — to prevent or treat postpartum haemorrhage (too much bleeding)

Oxytocin helps babies with Prader Willi syndrome to feed.

Having oxytocin is not suitable in all situations — your doctor can tell you if oxytocin is right for you.

It can also be a medicine used for termination of pregnancy.

Resources and support

Call healthdirect on 1800 022 222 (known as NURSE-ON-CALL in Victoria) for more information and advice. A registered nurse is available 24 hours a day, 7 days a week.