00:00 / 00:00
0 / 18 complete
Amenorrhea means no menstruation, and that’s normal in females before puberty, during pregnancy and lactation, and after menopause.
Now, for menstruation to happen, a female must normal anatomy and a functioning hypothalamo-pituitary-ovarian axis.
In other words, the hypothalamus must secrete gonadotropin releasing hormone, or GnRH, to stimulate pituitary production of FSH and LH.
And, finally, the ovarian follicles must secrete estrogen and progesterone in response to FSH and LH stimulation.
In childhood and early adolescence, estrogen leads to the development of secondary sex characteristics - like the development of breasts, and the appearance of axillary and pubic hair.
And eventually, usually 2 to 3 years after the breasts have started developing, the first menstruation, or the menarche, occurs.
Menstruation marks the beginning of the menstrual cycle, and that cycle repeats every 28 days on average from puberty until menopause. Ovulation happens on day 14 of this average 28 day cycle.
If the oocyte is fertilized by a sperm, then the remains of the follicle keep secreting estrogen and progesterone to help with pregnancy until the placenta develops, and no menstrual bleeding occurs.
In the absence of pregnancy, estrogen and progesterone levels gradually decrease, and when they get really low, on day 28, this leads to menstruation, and the beginning of a new cycle.
So physiology aside, primary amenorrhea is when a female has not begun breast development by age 13 or hasn’t had menarche by age 15.
Amenorrhea is the absence of menstrual periods in a woman of reproductive age. There are two types of amenorrhea: primary and secondary. Primary amenorrhea is the failure to menstruate by the time a girl has reached 16 years of age. Secondary amenorrhea is the absence of menstrual periods for six months or more in women who have previously had at least one menstrual period.
Amenorrhea can be caused by a number of things such as stress, exercising too much, hormonal problems, and pregnancy.
Latest on COVID-19
Nurse Practitioner (NP)
Physician Assistant (PA)
Create custom content
Raise the Line Podcast
Copyright © 2024 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Cookies are used by this site.
Terms and Conditions
USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.