The Conservatives have highlighted official figures that show after a decrease, the number of deaths is beginning to rise again.
Jackson Carlaw, the party's health spokesman said screening facilities need to be made as accessible as possible.
Official NHS statistics show that in 2012, the last year with full numbers available, there were 1063 deaths from breast cancer in Scotland, the third consecutive annual increase. The figure for 2009 was 1002.
Cervical cancer deaths also increased for the second successive year to 112.
Mr Carlaw said the hard work and improvements of previous years must not be lost: "Terrific work has been done over the years by charities and the NHS to raise awareness around these two potentially deadly diseases," he said.
"But it's important, as numbers have improved over the long-term, we don't allow complacency to creep in."
High profile cases of celebrities diagnosed with cancer like Jade Goody, who died in 2009 and Kylie Minogue who survived breast cancer following surgery and treatment in 2005, have been credited with increasing awareness.
However, the Tories say screening targets have still not been met.
They want women to be able to access screening at hours which can fit in with work and family commitments and allow more to get checked.
The breast cancer death rates went from 1105 in 2002 to a high of 1144 in 2005, before dropping to a low of 1002 four years later.
Cervical cancer mortality rates also peaked in 2005 before dropping the following year to a low of 92.
Since then the number has gone up and down but the trend has been upwards till the latest figure of 112 across Scotland last year.
Mr Carlaw added: "It's important we redouble our efforts, particularly around screening, to make sure we can return to the downward trend.
"By making screening facilities more accessible, particularly at evenings and weekends, we would surely be able to encourage more through the door.
"It would be extremely regrettable if decades of hard work on this issue were allowed to slip."