Evaluation of follicular growth patterns by ultrasound combined with measurement of circulating reproductive hormones has allowed designation of three functionally critical follicular sizes during the final stages of follicular growth: emergence (-4 mm), deviation (-9 mm), and ovulation (variable from 10 to 20 mm). Classification of anovulatory conditions on the basis of these three critical points is logical and provides for rational diagnosis and treatment of the underlying physiological condition. In extreme undernutrition, there is growth of follicles to emergence but not to deviation; however, the underlying pathophysiology is not defined because of relatively few scientific investigations of this condition. Anovulatory conditions with growth of follicles to deviation but not to ovulatory size have been extensively studied. Undernutrition and/or suckling can cause this @entity558 . It is characterized by a greater negative feedback effect of @entity53 on @entity1176 /LH pulses than found in normally cycling @entity291 . Another @entity558 that is common in high producing lactaing dairy @entity291 is characterized by growth of follicles to larger than ovulatory size, such as is observed in @entity291 with @entity7979 . This condition is characterized by an insensitivity of the hypothalamus to the positive feedback effects of @entity53 . Thus, these last two common anovulatory conditions appear to be primarily due to changes in the responsiveness of the hypothalamus to @entity53 . Treatments that increase circulating @entity1420 concentrations can help in the treatment of these two conditions by potentially altering GnRH/LH pulses and allowing the final stages of follicular growth or resetting the hypothalamic responsiveness to the positive feedback effects of @entity53 .

Physiological classification of anovulatory conditions in XXXX .

@entity558 :: ('MESH:C536528', 'Disease') :: ['anovulatory condition'] @entity7979 :: ('MESH:D005497', 'Disease') :: ['follicular cysts'] @entity1420 :: ('MESH:D011374', 'Chemical') :: ['progesterone'] @entity53 :: ('MESH:D004958', 'Chemical') :: ['estradiol'] @entity1176 :: ('MESH:D007987', 'Chemical') :: ['GnRH'] @entity291 :: ('9913', 'Species') :: ['cows']
@entity291 :: (9913,Species) :: ['cattle']
