00:00 / 00:00
Androgen insensitivity syndrome
Hypospadias and epispadias
Benign prostatic hyperplasia
Male hypoactive sexual desire disorder
Premature ovarian failure
Polycystic ovary syndrome
Sex cord-gonadal stromal tumor
Surface epithelial-stromal tumor
Germ cell ovarian tumor
Pelvic inflammatory disease
Female sexual interest and arousal disorder
Genito-pelvic pain and penetration disorder
Fibrocystic breast changes
Paget disease of the breast
Preeclampsia & eclampsia
Intrauterine growth restriction
Congenital cytomegalovirus (NORD)
Neonatal herpes simplex
Congenital rubella syndrome
Gestational trophoblastic disease
Fetal hydantoin syndrome
Fetal alcohol syndrome
Disorders of sex chromosomes: Pathology review
Disorders of sexual development and sex hormones: Pathology review
Sexually transmitted infections: Vaginitis and cervicitis: Pathology review
Sexually transmitted infections: Warts and ulcers: Pathology review
HIV and AIDS: Pathology review
Penile conditions: Pathology review
Testicular and scrotal conditions: Pathology review
Prostate disorders and cancer: Pathology review
Testicular tumors: Pathology review
Uterine disorders: Pathology review
Ovarian cysts and tumors: Pathology review
Cervical cancer: Pathology review
Vaginal and vulvar disorders: Pathology review
Benign breast conditions: Pathology review
Breast cancer: Pathology review
Complications during pregnancy: Pathology review
Congenital TORCH infections: Pathology review
0 / 20 complete
0 / 9 complete
antiandrogens p. 682
cirrhosis p. 398
Cushing syndrome p. 354
cystic fibrosis p. 58
ectopic pregnancy and p. NaN
menopause p. 652
Müllerian agenesis p. 646
PCOS p. 670
pituitary adenoma and p. 544
pituitary prolactinomas p. 335
Turner syndrome p. 661
Amenorrhea means no menstruation.
It’s normal before puberty, during pregnancy and lactation, and after menopause.
Sometimes though, menstruation either never starts, which is called primary amenorrhea, or suddenly stops in a person who’s previously menstruating, which is called secondary amenorrhea.
Now, menstruation, and the menstrual cycle as a whole are controlled by the hypothalamus and the pituitary gland, all the way up in the brain.
The hypothalamus secretes gonadotropin-releasing hormone, or GnRH, which makes the nearby anterior pituitary gland release follicle-stimulating hormone, or FSH, and luteinizing hormone, or LH.
In the first two weeks of a normal 28-day cycle, the ovaries go through the follicular phase, meaning that out of the many follicles scattered throughout the ovaries, a couple of them enter a race to become the dominant follicle, that will be released at ovulation.
All the developing follicles secrete loads of estrogen, which negatively inhibits pituitary FSH.
In the meantime, the uterus goes through two phases: the menstrual and proliferative phase.
During the menstrual phase, the functional layer of the endometrium is shed and eliminated through the vagina, leading to menstruation, which lasts an average of five days.
Amenorrhea is the absence of menstrual periods in women during reproductive years. There are two types of amenorrhea: primary and secondary. Primary amenorrhea is when periods have never started by the time a girl reaches 16 years old. Secondary amenorrhea is when periods have stopped for at least three months, even if they had started in the past.
There are many possible causes of amenorrhea, including pregnancy, hormone problems, problems with the ovaries or uterus, eating disorders, excessive exercise, and stress.
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