McKinson chalked up a 40-35 points success over Duane Green to take his record to 10-0 on Saturday.
The 22-year-old’s partner witnessed the victory before the pair dashed off to hospital in readiness for their new arrival.
McKinson said: ‘My girlfriend’s being induced – that’s why I had to box first.
‘I had to concentrate on the fight, but my girlfriend was here watching me and then had to go to hospital!
‘It’s a girl and she’s a week overdue so they are starting her off.
‘So it was tough to think of the fight but I had to get in there and do it.
‘I’ve been training hard and that’s probably my best win to date.
‘I spoke to the ref after and he said he was close to jumping in – and this guy doesn’t get stopped.’
Danny Couzens was a wide 40-35 points win over Hungarian Istvan Orsos
He said: ‘It was a good performance against a tough boy. I used the jab well and I stuck to my boxing and kept my concentration.
‘I just enjoyed it and I felt I beat him comfortably.
‘I thought the ref had jumped in to wave it off in the final round but he gave him a standing count.
‘But he took the shots and I was throwing some serious leather in there.
‘I felt strong and now want to push for a title in March.’
Dave Birmingham got his second career stoppage as he took out Dave Miko in five rounds.
He said: ‘The gameplan went out of the window a bit.
‘They said they wanted me to feel him out – but that doesn’t happen with me!
‘I realised early on the body shots were hurting him, and I love a body shot.
‘The corner said to pepper him rather than look for big shots. I felt he was going to go in the fourth but it was just a matter of time.
‘This sets me up for a good Christmas and then I’m looking for titles in 2017.’
In other contests, Southampton pair Charlie Quinn and Jimmy Cooper grabbed points wins with Bournemouth’s Sam Jones doing likewise.