How does menstrual cycle begin, Biology

Assignment Help:

Does the hypophysis-ovaries endocrine axis work in the same way during pregnancy as in non-pregnant women? If pregnancy does not occur how does another menstrual cycle begin?

The functioning of the hypophysis is changed during pregnancy. As estrogen and progesterone levels remain elevated during the gestational period the production of GnRH (gonadotropin-releasing hormone) from the hypothalamus is inhibited. The lack of GnRH therefore inhibits the secretion of FSH and LH from the hypophysis and a new menstrual cycle does not start.

If pregnancy does not happen the lowering of estrogen and progesterone levels stimulates the production of GnRH by the hypothalamus. This hormone then hastens the adenohypophyseal secretion of FHS and LH that in their turn stimulate the maturation of follicles and the starting of a new menstrual cycle.

 


Related Discussions:- How does menstrual cycle begin

Do plants have tissue organization and specialized organs, Do plants have t...

Do plants have tissue organization and specialized organs? Plants have specialized organs (as reproductive organs, roots, limbs, leaves) and differentiated tissues (vascular t

Vitamin C, What is pasteurization of fruit juice?

What is pasteurization of fruit juice?

Define body building functions of proteins, Define Body Building functions ...

Define Body Building functions of proteins? The primary functions of proteins, as you might be aware, is tissue growth and maintenance. Protein contains amino acids - the build

Statistical investigation, Meaning of Statistical Investigation: An inv...

Meaning of Statistical Investigation: An investigation means a systematic search for the knowledge or the truth. In statistical investigation the search for the knowledge is do

Define briefly about the nutrition security, Define Briefly about the Nutri...

Define Briefly about the Nutrition security? Nutrition security can be briefly defined as a balance between biological requirements in energy and nutrients and the quantity and

What happens at the molecular level, An enzyme isolated from a mutant bacte...

An enzyme isolated from a mutant bacterium grown at 20 degrees celsius works in a test tube at 20 degrees celsius but not at 37 degrees celsius( 37 degrees celsius is the temperatu

Drowning - paediatric emergencies, Drowning: Drowning is a cause of a...

Drowning: Drowning is a cause of accidental death  in children Accidental drowning may occur because children  do not  have adequate protective supervision.  It may be defined

Protozoa, What spices is protozoa

What spices is protozoa

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd