Mrs Vincent, whose two sons are now 6 and 8 years old, said paid parental leave was tricky for employers. If people did not keep up with their "professional practice", then any training invested in them may not be as valuable when they returned.
"I became pregnant with my eldest son and I stayed at home with my children and I've just gone back to part-time work this year," Mrs Vincent said. "I went back voluntary first so I could upskill myself."
However, she felt parents needed to be given enough time to spend with their new-born children. "I think it would be vital for breast feeding, for bonding ... if one or both parents could have at least six months off with their child."
The Business NZ submission said employers struggled to find suitable temporary staff to fill parental leave vacancies.
"Employers who have been forced to bear considerable replacement costs, or to find those amongst their other employees willing to provide cover, may well think hard before again employing a woman of child-bearing age."
After the presentation, Business NZ employment relations manager Paul Mackay told reporters the additional proposed leave allowance may cost more for employers as parents would lose their sharp edge in their workplace.
Employment law specialist Blair Scotland of law firm Chen Palmer said extending the period was unlikely to make any difference to people who already discriminated against women because of leave allowances.
"Regardless of what you do, there will potentially be a very small percentage of employers out there who will do that."
Mr Scotland said it was unclear how additional training costs could be associated with longer leave allowances.
"Parents, men, women can take up to that 52 weeks [unpaid parental leave] anyway. It's difficult to see where that additional cost comes from," he said.
Ms Moroney said the Business NZ submission was outdated and unfairly singled out women.
"It is out of step with what I understand modern-day employer attitudes are towards women and I cannot explain, for the life of me, why an organisation like Business NZ would come to select committee with this type of written submission."