Chris Keates, general secretary from the NASUWT union, said teachers and students had battled with new syllabuses that have been introduced in this year and may impact results.
A Department for Education speaker stated: #8220;Content for the 2015 A-level subjects was printed in April 2014 following extensive consultation using the education sector which started in May 2013.
Ms Keates stated the alterations would particularly affect individuals receiving their AS-level results #8211; the first group to undergo the brand new curriculum.
The amount of boys experienceing this top A* grade could pull further in front of women this year due to the increase in the take-from maths, based on Professor Alan Smithers, director from the Center for Education and Employment Research at Buckingham College.
Experts will also be predicting a small rise in the amount of top A* along with a grades because of greater figures of pupils sitting maths and additional maths #8211; typically high-scoring subjects.
This past year, boys held b .9% lead over women in a- grade, although women had a 0.4% lead in a along with a- grade combined #8211; getting out-carried out boys every year since 2000.
Students are bracing themselves for unpredictability within the results, which teachers#8217; unions are blaming on changes towards the curriculum.