Rising numbers of women consultants could lead to a long-term decline in productivity, academics have warned.
Researchers looked at the number of hospital episodes conducted by 8,284 consultants and found that women saw around 160 fewer patients a year than men.
They warned that recent increases in medical school intake might not translate into the expected rise in NHS productivity because a growing number of students were women.
Karen Bloor, co-author of the research, published in this month's Journal of the Royal Society of Medicine, said the study did not take into account non-medical work.
"Women may just take on a different balance of management and teaching, or be spending more time with patients," she noted.
NHS Employers lead on employment issues Andrea Hester said: "Women are more likely to work part-time and have care responsibilities."
Meanwhile, figures from the Office for National Statistics released this week show NHS productivity in general has dropped by an average of 1 per cent each year from 1995-2006.
Read this week's leader for more analysis.