polyovulatory

Polyovulatory refers to the occurrence of multiple ovulations within a single reproductive cycle, resulting in the release of more than one oocyte (egg). In contrast, monoovulatory cycles yield a single dominant follicle and ovum. In humans, most cycles are monoovulatory, but polyovulatory cycles can occur naturally when more than one follicle reaches maturity and ovulates. When two or more ova are released and fertilized, dizygotic (fraternal) twins may result. In many other mammals, polyovulation is common and part of normal reproductive biology, with some species capable of releasing several oocytes in a single cycle.

Causes and influences of polyovulation include hormonal factors that regulate follicle development, particularly levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Genetic factors can also predispose certain individuals or populations to higher rates of multiple ovulations. Medical or assisted-reproduction interventions that stimulate the ovaries, such as clomiphene citrate or gonadotropin injections, can increase the number of developing follicles and promote polyovulation.

Clinical and reproductive implications of polyovulation center on the potential for multiple gestations. When multiple ova are fertilized, the risk of twins or higher-order multiples rises, which is associated with heightened maternal and fetal risks, including preterm birth and complications related to multiple placentas. Not all polyovulatory cycles lead to multiple pregnancies, as fertilization and implantation of each ovum are required for a multiple-gestation outcome.

Detection of polyovulation can involve ultrasound monitoring of follicular development and hormonal assessments. After ovulation, the presence of multiple corpora lutea can indicate that more than one ovum was ovulated.