A senior midwife has issued an appeal to missing Constance Marten, the aristocrat who vanished more than a month ago with her convicted sex offender boyfriend and their newborn baby.

The couple and baby have not been seen since January 8 and police believe that at the moment they could be anywhere in the UK.

Shereen Nimmo, director of midwifery for Barts Health NHS Trust, said: “Constance, my name is Shereen and I’m here to speak to you as a midwife and a mother. I am not here to judge you but here to help you and your baby.

“I know that you really love your baby, and I know what an exciting and worrying time being a mum can be. And I want to make sure that you and your baby are OK and get the care you need.

READ MORE: Police believe missing couple and newborn sleeping in tent

The Bolton News: Constance captured by CCTV in EssexConstance captured by CCTV in Essex (Image: PA/GMP)

“After you have a baby, midwives are there to check you are recovering physically and emotionally and adjusting to caring for your newborn.

“We check your baby is feeding properly and putting on weight, and they have screening tests to make sure their heart, hearing, hips and eyesight all look OK.

“We also check for some rare conditions and put care plans in place to support them if needed.

“But it’s not too late to have these checks done and to make sure your baby is healthy.

“You’re putting your baby at risk by not accessing medical care, so it’s really important that you come and see a midwife, doctor or another healthcare professional as soon as possible.

READ MORE: Mother of missing aristocrat Constance Marten tells daughter: I will support you

“Babies need a safe, warm environment and all new mums are given information about safe sleeping for their baby to prevent sudden infant death syndrome.

“We know the safest place for your baby to sleep is in a cot in the same room as you. Sleeping with your baby in an unsafe environment puts them at risk.

The Bolton News: The couple captured by CCTVThe couple captured by CCTV (Image: PA)

“We’re worried that without access to midwifery and medical care, your baby might not be getting the best start in life that we know you want for them.

“Please do the right thing for your baby and go to your nearest healthcare facility so my caring colleagues can take care of you and your baby. All we want to do is help you.”

Constance, 35, and her partner Mark Gordon, 48, have been travelling around the UK by taxi since their car was found burning on the M61 in Bolton, on January 5.

Authorities believe the couple have been sleeping rough in a blue tent, and fear for the safety of the baby who has not had any medical attention since birth in early January.

It is unknown if the baby was full-term or has any health issues, which is why officers want to find the family.

The missing couple have so far avoided being traced by the police by moving around frequently and keeping their faces covered in CCTV images.

READ MORE: £10K reward offered for Constance Marten information

Detective Superintendent Lewis Basford said around 50 officers are working on the case at any one time and more than 630 hours of CCTV has been viewed.

He said there have been more than 350 calls to police from the public with information following previous appeals.

The Bolton News: The couple captured by CCTV getting into a taxiThe couple captured by CCTV getting into a taxi (Image: PA)

Miss Marten, who is from a wealthy aristocratic family, was a promising drama student when she first met Mr Gordon in 2016.

Since then, the couple have led an isolated life, and in September, when Miss Marten was well into her pregnancy, began moving around rental flats.

Gordon served 20 years in prison in the US for rape and battery committed when he was 14.