What is HPO axis dysfunction?

The hypothalamic-pituitary-ovarian (HPO) axis is a tightly regulated system controlling female reproduction. HPO axis dysfunction leading to ovulation disorders can be classified into three categories defined by the World Health Organization (WHO).

When does the HPO axis mature?

With futher maturation of the HPO axis a pattern of regular ovulatory cycles emerges, and in women 11 years after menarche by age 18 but a basic evaluation is indicated if menarche does not occur by age 16 or if secondary sexual development does not being by age 14.

What is immature HPO axis?

One cause or anovulation may be an immature hypothalamic-pituitary-ovarian axis. The fact that initial menstrual cycles are usually irregular and often anovulatory implies that a maturation process is taking place in the HPO axis and that cyclic ovulatory menstruation begins only when adequate maturation occurs.

What is HPG axis?

The hypothalamic-pituitary-gonadal (HPG) axis coordinates a tightly regulated feedback loop that consists of gonadotropin-releasing hormone (GnRH) produced by the hypothalamus; follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary; and the sex steroids estrogen, progesterone, and …

What are the 3 types of HPO axis disorders?

HPO axis dysfunction leading to ovulation disorders can be classified into three categories defined by the World Health Organization (WHO). Group I ovulation disorders involve hypothalamic failure characterized as hypogonadotropic hypogonadism. Group II disorders display a eugonadal state commonly associated with a wide range of endocrinopathies.

Is the HPO axis part of the maturation process?

The fact that initial menstrual cycles are usually irregular and often anovulatory implies that a maturation process is taking place in the HPO axis and that cyclic ovulatory menstruation begins only when adequate matur … One cause or anovulation may be an immature hypothalamic-pituitary-ovarian axis.

Is the immature HPO axis a cause of anovulation?

The immature HPO axis One cause or anovulation may be an immature hypothalamic-pituitary-ovarian axis. The fact that initial menstrual cycles are usually irregular and often anovulatory implies that a maturation process is taking place in the HPO axis and that cyclic ovulatory menstruation begins only when adequate matur …

How are FSH and LH levels related to HPO axis?

FSH and LH levels in prepubertal and pubertal females offered no statistical data by which to measure the maturity of the HPO axis, although consistently low levels may be meaningful. Data support the concept that idiopathic sexual precocity is a premature maturation of the HPO axis.