Lancashire Police have referred themselves to the police watchdog over contact the force had with missing Nicola Bulley prior to her disappearance.
The Independent Office for Police Conduct (IOPC) said it was assessing the information to determine whether an investigation would be necessary over the contact officers had with the mother-of-two on January 10.
The referral comes after Ms Bulley’s family called for an end to the “speculation and rumours” about her private life.
Police were criticised for disclosing that she suffered “some significant issues with alcohol” in the past, which had resurfaced over recent months.
After the force revealed her issues with alcohol “brought on by her ongoing struggles with the menopause”, they were strongly condemned by MPs and campaign groups.
Confirming a referral had been made to the watchdog, a spokesman for the IOPC said: “This afternoon we received a referral from Lancashire Constabulary regarding contact the force had with Nicola Bulley on January 10, prior to her disappearance.
“We are assessing the available information to determine whether an investigation into that contact may be required and if so, who should conduct that investigation.”
A source close to the Home Secretary said Suella Braverman was “concerned” by the disclosure of Ms Bulley’s personal information and “asked the force for an explanation”, which the source said was received on Thursday evening.
The Home Office said it was receiving regular updates from the force about its handling of the case – including “why personal details about Nicola was briefed out at this stage of the investigation”.
The Conservative police and crime commissioner for Lancashire, Andrew Snowden, said the force was being “as transparent as they can be” following the press conference.
Ms Bulley vanished after dropping off her daughters, aged six and nine, at school on January 27 in St Michael’s on Wyre, Lancashire.
She was last seen at 9.10am taking her usual route with her springer spaniel Willow, alongside the River Wyre.
Her phone, still connected to a work call for her job as a mortgage adviser, was found just over 20 minutes later on a bench overlooking the riverbank, with her dog running loose.
In a statement issued on Thursday, Ms Bulley’s family said people needed to stop “making wild theories up” about her private life.
The statement, issued through the force, said: “We, as a family, believe that the public focus has become distracted from finding Nikki, and more about speculation and rumours into her and Paul’s private life.
“As a family, we were aware beforehand that Lancashire Police, last night, released a statement with some personal details about our Nikki.
“Although we know that Nikki would not have wanted this, there are people out there speculating and threatening to sell stories about her. This is appalling and needs to stop.”
It continued: “The public focus has to be on finding her and not making up wild theories about her personal life.
“Despite what some media outlets and individuals are suggesting, we are being updated daily and receive support from our family liaison officers.”
Concluding their statement, Ms Bulley’s family issued a direct plea for her to return, saying: “Your girls want a cuddle.”
The statement read: “Nikki is such a wonderful daughter, sister, partner and mother and is missed dearly – we all need you back in our lives.
“Nikki, we hope you are reading this and know that we love you so much and your girls want a cuddle. We all need you home.
“You can reach out to us, or you can contact MissingPeople.org.uk. Don’t be scared, we all love you so very much.”