Primary Amenorrhea

Primary Amenorrhea: The age is over 14 or 16 years, and have no menstrual cycle, no secondary sexual characteristics. In general, menstruation period can occur in two years after secondary sexual characteristics.

Classification of primary amenorrhea base on the causes:

1. The genital abnormalities:

1) imperforate hymen: result in the urogenital sinus epithelium no through to the vulva, vestibular. The normal ovary growth and secondary sexual characteristics. In adolescent often found cyclical abdominal pain, vaginal cavity have blood mass, serious can cause frequent urination, urinary retention and constipation.

2) congenital absence of vagina: Vice mesonephric duct dysplasia.

3) congenital absence of the uterus.

2. Endocrine disorder:

1) low thyroid hormone: thyroid stimulating hormone TSH> 10μIU/ml. Adolescent low thyroxine can cause slow metabolism, slow down mature gonadal axis, the extension of late menstrual. Early stage low thyroid hormone could be combined with Gonadal dysgenesis, a poor prognosis.

2) high prolactin hyperandrogenism: prolactin PRL> 30-40ng/ml, may be accompanied by galactorrhea, a giant pituitary adenoma or microadenoma or empty sella syndrome. High PRL can suppression of FSH and GnRH to cause low estrogen and amenorrhea, if adolescent onset, is primary amenorrhea.

3. Others:

1) inflammation: childhood meningitis, encephalitis affecte hypocretin. Or tuberculous peritonitis cause endometrial tuberculosis, endometrial scar, result in the uterus primary amenorrhea.

2) injury: early surgical resection of malignant ovarian tumor of the uterus, in particular germ cell tumor, the prognosis is better, can survive, but lead to primary amenorrhea. Or radiation therapy cause pituitary and ovarian damaged.

3) nutritional: Poor nutrition can cause amenorrhea, cause poor development.