How common is haemophilia, as seen on Call the Midwife?

Lorna Pryce comes into the maternity clinic with her doting mother and later in the episode, gives birth to baby Ian. As the pair recover after the birth, Dr Patrick Turner (Stephen McGann) notices that Ian has a cephalohematoma, a birth injury caused by trauma to the infant's head. "It's simply a bruise under the scalp from where we had to give him a tug with the forceps," he explains.

Later on, Dr Turner and Shelagh (Laura Main) notice multiple bruises on Ian's body, which means Dr Turner has to refer the newborn to the paediatrician at St Cuthbert's Hospital. They later learn that baby Ian has haemophilia and when checking Lorna's medical records, find out that her father also had the rare blood condition and died from a fatal fall at age 29.

"They're bringing his bleeding under control but the diagnosis is going to hang over them for the whole of his life," Dr Turner says.

But what is the blood condition and how common is it? Read on for everything you need to know about haemophilia, as discussed in Call the Midwife episode 3.

What is haemophilia?

Haemophilia is a rare condition that affects the body's ability to clot. For example, if someone was to suffer a cut, the substances in your blood (known as clotting factors) mix with blood cells (platelets) to make your blood sticky and form a clot. This eventually makes the bleeding stop.

However, those with haemophilia do not have as many clotting factors as they should have in their blood. So, this means they bleed for longer than usual.

The symptoms can range from mild to severe but may include having nosebleeds that take a long time to stop, bleeding gums and skin that bruises easily.

How common is haemophilia?

The condition is classified as rare, with it mainly affecting the male population.

According to research done at UCL, about 6,000 people in the UK have haemophilia, with most of them being male because of the way the condition is inherited.

If you have a family history of haemophilia, like in episode 3 of Call the Midwife, the chances for male newborns to have the condition are also high but tests during pregnancy can diagnose haemophilia in the baby.

There's no cure for haemophilia, but treatments – like man-made clotting factors prescribed as medicine or injections – usually allow a person with the condition to enjoy a good quality of life.

How is haemophilia explored in Call the Midwife?

Lorna is unaware of the blood condition and the way her father died, and it's obvious that her mother shielded her from the information so as not to worry her. "You might only have had girls," she cries.

Even so, baby Ian has haemophilia and we see him with tiny bruises and bleeding in the third episode. As Dr Turner explains: "It affects boys almost exclusively... it means that if Ian hurts himself, he may bleed very badly and need hospital treatment to help his blood to clot."

The doctor has to be plain about the fact that sometimes, life expectancy is affected, adding "your father lived to be almost 30 and they're making medical advances all the time".

Call the Midwife airs on BBC One on Sundays at 8pm and is also available to stream on BBC iPlayer.

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