Like most new mums, Nicky Rigby was exhausted in the months following the birth of her first baby. The 26-year-old put the overwhelming tiredness, as well as her sudden weight loss, down the demands of caring for daughter Lily.

But the young mum was actually suffering from Type 1 diabetes and died as a result of not getting treatment for the undiagnosed condition.

Her grieving family is now encouraging all new mums to pay close attention to how they are feeling and to seek medical attention if they are unwell.

"Please don’t battle on through exhaustion like my brave Nicky tried to do," Nicky’s devastated fiance Mark Wilson told UK's Daily Mail.

Nicky, from Wirral in north-west England, died after Mark returned home to find her found unconscious on her bed in July 2012. An inquest was later told she had suffered from undiagnosed Type 1 diabetes. As a result her oesophagus gradually deteriorated and lead to her death.

Mark said the most difficult thing about losing his partner was knowing she would not get to see their daughter grow up.

"Nicky was a natural with Lily, cuddling and feeding her. She loved being a mum, despite the sleepless nights leaving her feeling exhausted," he said.

"She didn’t want anyone fussing over her. She just said that all mums get tired like she was."

Nicky did eventually go to the doctor, but she was only prescribed iron tablets. Mark said the tablets didn't help at all.

On Mark’s birthday in July 2012, when Lily was only five months old, Nicky was feeling unwell. She decided to have an early night but encouraged her fiance to go out with friends to celebrate.  

"Nicky wasn’t feeling great and insisted I go and enjoy myself. I kissed her goodbye then took Lily round to my mum’s house so Nicky could have a rest," Mark said.

But when Mark returned home later that night and went to check on Nicky he was faced with a horrifying scene.

"I decided to switch on the light to see if Nicky was okay, and then saw she was surrounded by black vomit," he said.

He called an ambulance and tried unsuccessfully to revive Nicky. The paramedics arrived soon after, but were unable to revive her. 

An inquest into Nicky's death heard the new mum had died from diabetic ketoacidosis, which is caused by consistently high blood glucose levels.

It occurs when a severe lack of insulin leads to the body not being able to use glucose for energy. Instead, the body begins to break down other tissue to use as an alternative energy source.

The inquest was told Nicky would be alive today if her condition had been diagnosed and treated with insulin injections to control her blood sugar levels. It is not known whether pregnancy played any part in the onset of Nicky’s condition, however Type 1 diabetes is different to gestational diabetes, which is routinely check for during pregnancy.

A grieving Mark said he's determined to make sure his daughter grows up knowing how special her mother was. He has put photos of Nicky around the house and made his daughter a memory box which contains a gold heart necklace he gave to Nicky, as well as her engagement ring.

“I want Lily to look at the pictures of her mum and know she was a brilliant, fun person,” he told the Daily Mail.

Type 1 diabetes: The symptoms to look out for

* Excessive thirst

* Frequent urination

* Weight loss

* Fatigue

* Visual disturbances, such as blurred vision

* Itching skin, particularly around the genitals

* Nausea and vomiting

See your doctor if you're worried about any symptoms.