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How do anovulation and oligoovulation differ?
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infertility
Major structures and hormones involved in the initiation of pregnancy. Also seen, at right, is the development of an egg cell (ovum) from follicle to embryo.
Anovulation and oligoovulation are both common disorders of ovulation that contribute to female infertility, but they differ in the frequency of the ovulatory process:12
- Anovulation is defined as the complete failure to ovulate. In this condition, an egg is not released from the ovary, making natural conception impossible without medical intervention.12
- Oligoovulation refers to the occurrence of very irregular ovulatory cycles. While ovulation still takes place, it happens infrequently, which significantly reduces the window of opportunity for conception and often leads to difficulty in achieving pregnancy.12
Both conditions are frequently linked to hormonal imbalances or underlying dysfunctions involving the hypothalamus, pituitary gland, or ovaries. Clinicians may use various diagnostic tools, such as tracking basal body temperature, monitoring luteinizing hormone levels, or performing pelvic ultrasound examinations, to distinguish between these disorders and determine the appropriate course of treatment.31