A hens breed will usually give you an average timeframe for when they will lay and after that it then comes down to the individual. Some breeds are known to start laying early such as the Leghorn which can start laying as early as 4 months. Then there are breeds like the Brahma which usually do not start laying until at least 6-7 months. Another thing to consider is what season the hen sexually matures in and how many hours of daylight there are. For example, if a hen reaches sexual maturity in the fall when the daylight hours start to get shorter then she may not start laying until spring when the daylight hours start to increase again. As for egg size yes it is fairly common for new layers to lay smaller eggs at the start as well as there being some āglitchesā (odd shapes, irregular laying patterns, shell inconsistencies etc.).