The former textiles designer had wanted to join the force before her daughter Ivy, 4, was born, but had to lose 30 kilograms before she could be recruited.

"I had my goal in mind and nothing was going to stop me getting there.

"I lost 30 kilograms and I had knee problems as well, but I was able to finally start training in September 2009."

Ms Foster was among 51 recruits who graduated at the Victorian Police Academy in Glen Waverley on March 5 after 23 weeks' training.

There were 17 women and 34 men. A further 400 recruits continue training.

Ms Foster will now spend three weeks on the Safe Streets taskforce in the Melbourne CBD, followed by 10 weeks on booze buses. In May she will find out which station she will be based at and will begin duty there the following month.

"I want to make a contribution to society and go to work each day not knowing what I'm going to do. My husband, Phillip, has been very supportive but I guess he's had to be - when I put my mind to something I do it."

Ms Foster said her new job appealed because of its structure and rules.

"When I was in high school it's the last thing I would have wanted to do because of the discipline.

"I suppose I changed. I grew up and got some wisdom and maturity."

The biggest problems she expects to face are dealing with alcohol and drug crimes.

"I'm a little bit worried about how I'll be able to put my skills into practice.

"Now I'm looking forward to getting out there and making a contribution."