One in eight mums in Kirklees smoked through their pregnancy, figures reveal.
But the latest data shows north Kirklees continues to have a far worse record than Huddersfield.
Continuing to smoke while pregnant has long been known to harm babies and increase the chances of still birth, cot death and breathing problems such as asthma.
Cigarettes can restrict the essential oxygen supply to the baby, so their heart has to beat harder.
Figures published by the Health and Social Care Information Centre (HSCIC) show about one in seven pregnant women in north Kirklees carried on smoking.
Huddersfield mums-to-be were less likely to smoke with about one in ten still smoking when they gave birth.
Overall the figures for 2014/15 show another year-on-year improvement by pregnant mums with the lowest levels since records began in 2006/07.
But the north still has a long way to go match the healthiest areas of the country, such as London, where fewer than one in 20 pregnant mums smoke.
The worst area was Blackpool where more than a quarter of babies born were to mums who smoked.
A spokesman for Kirklees Council, said: “We are working very closely with maternity services in both north and south Kirklees to support women who are smoking while pregnant.
“We now have a specialist stop smoking advisor who is focussing only on north Kirklees, she has previously worked as a midwife and can provide excellent intensive one to one support to these women.
“There is a range of support available at home, phone, online and text.
“We are also going to re-launch The Pharmacy Stop Smoking Service and concentrate on areas with the highest prevalence such as north Kirklees and there are other projects such as Smokefree Play Areas which will begin this summer in Crow Nest Park, Dewsbury and Wilton Park, Batley.
“The aim of these is to make smoking feel less normal and for parents and adults to understand that evidence tells us that one reason children and young people take up smoking is because they see the adults doing it.
“We hope that all the programme of work makes it easier for those thinking about quitting and those wanting to stay smokefree.”
The improved figures come amid government threats to cut £200m from public health budgets at local authorities.
Louise Silverton, director for midwifery at the Royal College of Midwives, said: “Targets for reduction are fine but they need to be backed up with resources.
“What is needed is retention of local authority funding for family based smoking cessation to include pregnant women.
“We know that women in poverty are more likely smoke so extra help and support needs to be given.”
Support is available by calling freephone 0800 612 00 11, 0330 660 116 from a mobile or 01484 434675 there is information available online.
