Almost one in 10 women in Buckinghamshire smoke while pregnant, despite Government efforts to reduce smoking rates.
The Government said too many women are at risk of suffering a stillbirth or complications as a result of smoking, particularly those from deprived areas, and recognised it must do more to tackle the issue.
According to NHS Digital data, eight per cent of the mums who gave birth during the first three months of 2019 in the Buckinghamshire Clinical Commissioning Group area were smokers - which equates to 97 out of the 1,267 women who gave birth during that time.
This was the same as the rate seen the previous year, and higher than the six per cent target the Government wants CCGs to meet by the end of 2022.
Across England, a total of 145,876 mothers gave birth during the same three months.
Of these, 10 per cent were self-reported as smokers, down from 11 per cent one year earlier.
The NHS said only 33 out of 191 CCGs in England met the national target.
It warned that smoking during pregnancy can cause serious health problems, including complications during labour and an increased risk of miscarriage, premature birth, still birth, and sudden unexpected death in infancy.
Vicky Salt, policy manager at charity Action on Smoking and Health said: “These figures show a slight decline in rates of smoking during pregnancy compared to last year, however much more must be done to address the big variations in prevalence rates between local areas.
"Government must go further, and faster, if it is to achieve its national ambition to reduce smoking at time of delivery.
“This should include greater use of financial incentive schemes to support quitting and action to reduce smoking rates in women of childbearing age.
“Any delay will have a real cost in babies’ lives.”
A Department of Health and Social Care spokeswoman said: “While the number of women smoking in pregnancy is at a record low, too many women from deprived areas are still at risk of suffering the tragedy of a stillbirth or complications as a result of smoking.
“We know we must do more.
"We are determined to reduce these levels to six per cent by 2022 and as part of the NHS long term plan, every smoker admitted to hospital will be offered specialist support to quit smoking, with an emphasis on pregnant women and their partners.”