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

What are the cnidocytes, Q. What are the cnidocytes? What is the name of th...

Q. What are the cnidocytes? What is the name of the capsule inside the cnidocyte? What are the biological functions of this structure? Cnidocytes are specific cells present in

Horse diseases-epidemiology, Epidemiology Infection is transmitted   b...

Epidemiology Infection is transmitted   by direct contact between infected domestic and wild animals and susceptible livestock; by arthropod vector (Phlebotomus, Aedes and Cul

Explain about the calcium and hypertension, Explain about the Calcium and H...

Explain about the Calcium and Hypertension? Chronic inadequate intake of calcium may play some role in etiologies of hypertension. Calcium deficiency has been linked to hyperte

What is constrictive pericarditis, Q. What is Constrictive pericarditis? ...

Q. What is Constrictive pericarditis? Constrictive pericarditis is the sequelae of chronic fibrosis and thickening of the pericardium as a result of chronic inflammation. E

Types of synovial joint, TYPES OF SYNOVIAL JOINT - 1 .      BALL AND ...

TYPES OF SYNOVIAL JOINT - 1 .      BALL AND SOCKET JOINT - One bone forms a ball like head that fits into a socket formed in the other bone. Movement is possible in al

How is water''s importance to life, How is water's importance to life refle...

How is water's importance to life reflected in the normal range of internal pH values that living things are likely to have?

Why are additives used in foods?, Normal 0 false false fal...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Describe the stages of atherosclerosis, Describe the Stages of Atherosclero...

Describe the Stages of Atherosclerosis ? The process of atherosclerosis which gives rise to CAD marches in stages. The earliest recognizable pathologic lesions are the fatty st

What is a community, What is a community? What is the difference between th...

What is a community? What is the difference between the concepts of community and population? A community is a set of populations of living beings that live in the similar regi

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