It would mean that shared parental leave is extended from the current year to 64 weeks, in a move which the SNP leader described as a “gamechanger”.
The additional 12 weeks would be ring-fenced for the father on a “take it or leave it” basis in order to encourage take-up. SNP MPs would push for the policy to be introduced at Westminster, which has control over parental leave system.
Research suggests a link between longer paternity leave and greater involvement of fathers in the early lives of their children, but a minority take up their full entitlement.
Ms Sturgeon said: “The SNP in government is taking radical action to help young families – almost doubling free childcare, the baby box, our new Best Start Grant and Scottish Child
Payment and the women returners scheme to help women back into the workplace.
“But we also need to change societal expectations and make it easier for new dads to take time off with their children.
“Shared parental leave is a good thing, but take up remains stubbornly low. Based on international examples, our plan for ‘use-it-or-lose-it’ months available only to the dad – in addition to the year available to new mums – could be a gamechanger.”
It is among a package of parental rights which Nationalist MPs will fight for in the next election, including increased maternity pay to 100 per cent of average weekly earnings for the first 12 weeks, then 90 per cent for 40 weeks or £150, whichever is lower.
The party is also calling for an increase in statutory paternity leave, with the weekly rate of Paternity Pay at 100 per cent of average weekly earnings for one week then 100 per cent for two weeks or £150, whichever is lower.
Fathers should also be given the right to take paid leave for six antenatal appointments, rather than the current right of unpaid leave for two appointments.
An extension of legal protection against redundancy for pregnant mothers is also being called for, as well as those on shared parental leave, and adoption leave, and new parents for up to six months after their return to work.
Ms Sturgeon added: “Alongside our proposal for an increase of statutory pay, phased in over time, and stronger protections against redundancy for new parents, this plan could have a radical impact.
“A vote for the SNP is a vote to escape Brexit, end austerity and help families across Scotland.”
Less than a third (31 per cent) of eligible new fathers used paternity leave in the past year UK-wide compared to 32 per cent the previous year, according to research based on HMRC figures which emerged earlier this year.
The figures contrast with the rising number of women choosing to take maternity leave, which has risen by approximately 5 per cent in the past four years.
Low rates of statutory pay are believed to among the main reasons for the low take-up.
Nationalist MPs will also step up their campaign for powers over drugs laws to be handed over to Holyrood.
This will include a fresh call for legal drug consumption rooms to be piloted in Scotland, a move that has already been rejected by the UK Government.
Figures published earlier this year showed there were 1,187 drug-related deaths in Scotland in 2018 - 253 more deaths than in 2017 – an increase of 27 per cent.
Alison Thewliss, SNP candidate for Glasgow Central, said: “We are facing a public health crisis in Scotland and current UK drugs law is not working– that’s the reality. We desperately need a fresh approach to tackle this issue head on but Westminster politicians continue to stand in the way of progress.
“The Tories have consistently displayed a shocking lack of empathy towards people struggling with addiction.
“With a strong group of SNP MPs at Westminster, we will be able to turn the heat up on the UK government and demand that vital action is taken to tackle addiction and drug-related deaths in Scotland.
“Devolve drugs law to the Scottish Parliament now so that we can step in and save lives before anymore are lost. Vote SNP next month and together we can build a better, more progressive Scotland that works for everyone.”
Meanwhile, SNP Deputy leader Keith Brown has said votes in Scotland could be pivotal to “locking Boris Johnson out of power”.
A weekend poll showed the Tories had recovered after a dip in Scotland and could retain all or most of their 13 seats in Scotland. The SNP, though, is poised to make significant gains and could take upwards of 40 of the country’s 59 seats.
Mr Brown hit the campaign trail in Auchterarder, along with SNP candidate John Nicolson who is seeking to win the Ochil and South Perthshire seat.
“Only a vote for the SNP can help Scotland escape Brexit, lock the Tories out of power and put Scotland’s future in Scotland’s hands,” Mr Brown said
“And only the SNP can beat the Tories in Scotland. The prospect of five more years with Boris Johnson as Prime Minister will fill most Scottish voters with horror.
“After a decade of Tory austerity, Boris Johnson’s miserable plan is for more of the same – plus dragging Scotland out of the EU against our will.”
The SNP will launch their manifesto this week. Although they have ruled out a coalition with other parties, Ms Sturgeon has indicated that her MPs could be ready to back a Labour administration if Labour leader Jeremy Corbyn grants a transfer of power to Holyrood for a second referendum on independence.
Mr Brown added: “If we face another hung parliament, Scottish votes could determine who forms the next government.
“And, with the SNP as the challengers in every Tory held seat – and polls showing Labour trailing behind in third place – only SNP MPs can deprive Boris Johnson of a majority.
“Voting SNP is the key to locking Boris Johnson out of power.”