I once had a very dominant French Marans hen whose offspring for 7 consecutive years was always male.
Apart from that I noticed that any kind of stress (cold, overcrowding, malnutrition, disharmonious combination of breeding stock, dislike of the cock etc.) would lead to lots of male offspring while a harmonious combination, balanced diet, agreeable weather conditions, generous space and a good and caring cock which is actually sought-after by the hens will lead to 80-100% female offspring.
Of course these are just my observations with my various chicken breeds and flocks over the period of several decades.