Nicola Sturgeon’s Scottish National party is to offer new parents in Scotland a free “baby box” of clothes, nappies and toys, with a built-in mattress allowing the box to be used as a baby’s cot, in an effort to tackle infant poverty rates.

The measure will be based heavily on Finland’s “maternity package” scheme which has run for more than 80 years. With a 95% take-up rate, it has been credited with cutting the Finnish infant death rate from 10% to 0.2%.

Sturgeon will unveil the proposal in the SNP manifesto for May’s Holyrood election this Wednesday, in an effort to cement the party’s substantial 30-point lead over Labour.

The SNP leader is also aiming to pitch for green votes by offering to increase the Scottish greenhouse gas emissions target from a cut of 42% to 50% by 2020, despite simultaneously risking an increase in air traffic by abolishing air passenger duty in Scotland.

The SNP said the boxes, which are designed to be converted into a cot for newborns, would cost about £100 each, but would not disclose at this stage how much the policy was expected to cost, or whether it was specifically targeted at parents from the poorest backgrounds.

With Scotland’s infant death rate now down to 0.37%, Sturgeon indicated the baby box strategy was chiefly part of a wider policy to tackle infant deprivation, support poorer mothers and improve Scotland’s relatively bad rates of under-attainment in deprived areas.

With all Holyrood parties pledging far heavier investment in free nursery places and in Labour’s case an additional plan to double early years grants for poorer parents to £1,030, Sturgeon is hoping to outbid her rivals with an offer of 500 more health visitors, as well as a £600 maternity grant to low-income mothers.

“By providing every newborn with a baby box, we can help child health – and by providing greater support to new families, we will also help to tackle child poverty and improve the chances of some of our most deprived children,” Sturgeon told the Sunday Mail newspaper.

With the opinion polls now showing the SNP are likely to win a large majority of Scotland’s 73 constituency seats, opposition parties including Labour is focusing heavily on securing the maximum number seats from Holyrood’s 56 regional lists – seats selected using the second vote in Scotland’s proportional system.

Prof John Curtice, leading psephologist at Strathclyde University, has warned SNP supporters that casting their second, list vote for the SNP may be wasted. Under the Holyrood system, the party would not be given list seats if it held the vast majority of constituency seats.

In a new analysis for the Electoral Reform Society, Curtice projected that the SNP’s dominance meant it was likely to win 70 seats, a figure consistent with recent polls.

Willie Sullivan, the director of ERS Scotland, said the SNPs dominance of Scotland’s political scene could potentially stifle other opposition parties”. He suggested pro-independence voters ought to consider giving pro-yes parties such as the Scottish Greens or the socialist Rise coalition their second votes.

“The polls show the SNP achieving a majority through the constituency first-past-the-post part of the election. This is a bad sign for smaller parties, and a long way from the rainbow parliament of 2003 which many consider to be the high water mark of multi-party politics in Scotland,” Sullivan said.

This article was written by Severin Carrell Scotland editor, for on Sunday 17th April 2016 18.08 Europe/London © Guardian News and Media Limited 2010