Kate Ferdinand feels ''so useless'' when she's not around her stepchildren due to her ''terrible'' pregnancy migraines.

The former 'Only Way Is Essex' star - who is expecting her first child with her husband Rio Ferdinand - admits she feels so much ''guilt'' when she's unable to help with her stepkids - Lorenz, 13, Tate, 11, and nine-year-old Tia.

She shared: ''Saying all of this, there are still days I feel absolutely wiped out, have terrible migraines and I do just go back to bed. In all honestly those days I feel so useless and have been having terrible guilt that I'm not around for the kids and Rio is doing everything (sic)''

And Kate admits she has been ''losing her mind'' as she doesn't know how she feels from day to day.

She wrote: ''I've been pretty quiet on here recently. Honestly, I've just been so exhausted I don't know whether I'm coming or going ... how I've been feeling has been changing daily so I've found it hard to share anything because I don't really know how I feel myself ... any other pregnant women feeling the same? Or am I losing my mind?? (sic)''

And Kate admits she ''worries about everything'' and has been feeling ''all types of confused''.

In a lengthy post on her Instagram page, she added: ''It's such an amazing feeling having a little human inside of you, our family is so excited but it's also so scary being pregnant for the first time ... I worry about everything ... having 3 big kiddies to look after and feeling like a 'mum' already but actually not being through this experience before has me feeling all types of confused! I just wanted to share the reality of how I'm feeling, also some hope that I'm not alone (sic)''