# Anovulatory Bleeding Jones, K. and Sung, S. (2022) ‘Anovulatory Bleeding’, in _StatPearls_. Treasure Island (FL): StatPearls Publishing. Available at: [http://www.ncbi.nlm.nih.gov/books/NBK549773/](http://www.ncbi.nlm.nih.gov/books/NBK549773/) >[!Abstract] > Abnormal uterine bleeding associated with ovulatory dysfunction (AUB-O) or anovulatory bleeding, is non-cyclic uterine bleeding characterized by irregular, prolonged, and often heavy menstruation. It represents one of the identified causes of abnormal uterine bleeding (AUB), a frequently encountered chief complaint in the primary care setting affecting up to one-third of women of child-bearing age. Though commonly observed during menarche and perimenopause, it can present at any stage of reproductive life. AUB-O is a diagnosis of exclusion; other structural and physiologic etiologies of AUB should be ruled out by history, physical exam, or with laboratory analysis and imaging as appropriate. ## Notes - Why Ovulation Is the Key to Optimal Health - anovulatory bleeding is believed to be caused by a disturbance in the HPO-Axis - anovulation can be related to weight changes, stress or excessive exercise - Causes of Anovulation - Anovulation common in teens - anovulation common in PCOS - anovulation can occur during lactation %% [Open in Zotero](zotero://select/items/@jones2022) ## Highlights ### [[anovulatory bleeding is believed to be caused by a disturbance in the HPO-Axis]] > The etiology of AUB-O is believed to be rooted in a disturbance in the hypothalamic-pituitary-ovarian axis.[[2]](https://www.ncbi.nlm.nih.gov/books/NBK549773/#) ^gp1hi ### [[Anovulation common in teens]] > Physiologic anovulation is common at the beginning of reproductive life when the hypothalamic-pituitary-ovarian axis is not yet mature. ^5uut1 ### [[anovulation common in perimenopause]] > Near menopause, recruitment of a follicle may occur early, in the luteal phase, followed by precocious maturation of the follicle.[[4]](https://www.ncbi.nlm.nih.gov/books/NBK549773/#) This "luteal out-of-phase event" then results in high levels of circulating estradiol and increased menstrual volume.[[4]](https://www.ncbi.nlm.nih.gov/books/NBK549773/#) ### [[anovulation can occur during lactation]] > Physiologic anovulation can also occur during lactation. ^lnsya ### [[anovulation is common in PCOS]] > Pathologic anovulation often occurs secondary to an endocrine dyscrasia with polycystic ovarian syndrome (PCOS) being the most commonly implicated process.[[5]](https://www.ncbi.nlm.nih.gov/books/NBK549773/#) ^i-qlz > ### [[anovulation can be related to weight changes, stress or excessive exercise]] > AUB-O can also be related to weight loss or weight gain, psychological stress, excessive exercise, or medications that affect dopamine metabolism. ^6za78 [View Highlight](https://read.readwise.io/read/01gq006p032qvpbj4tsvb9na9e) ### [[causes of Anovulation]] > Various common etiologies of anovulation are as follows:[[3]](https://www.ncbi.nlm.nih.gov/books/NBK549773/#)[[6]](https://www.ncbi.nlm.nih.gov/books/NBK549773/#) ^a3xuu > • Hyperandrogenism (e.g., PCOS, congenital adrenal hyperplasia, androgen-producing tumors) > • Hyperprolactinemia > • Anorexia > • Excessive exercise > • Stress > • Thyroid dysfunction > • Primary pituitary dysfunction > • Premature ovarian failure > • Medications [View Highlight](https://read.readwise.io/read/01gq006z32qa5sp3sz8ffdhaq2)