* If the ovum is [[Reproductive_System_- Anatomy & Physiology#Fertilisation.2C_Implantation_and_Early_Embryonic_Development|fertilised]], the corpus luteum remains fully developed and active throughout at least part of the pregnancy. | * If the ovum is [[Reproductive_System_- Anatomy & Physiology#Fertilisation.2C_Implantation_and_Early_Embryonic_Development|fertilised]], the corpus luteum remains fully developed and active throughout at least part of the pregnancy. |