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

Types of surgery-pulmonary regurgitation, Types of Surgery :  Pulmonary va...

Types of Surgery :  Pulmonary valve replacement using pulmonary or aortic allograft is the procedure of choice. It increases R.V. ejection fraction, decreases R.V. end diastolic p

Qualitative test for specific sugars, what is another test for pentoses? wh...

what is another test for pentoses? what is the positive result for this test?

Importance of forests - habitat and food, Importance of Forests - Habitat a...

Importance of Forests - Habitat and Food Forests provide habitat, and food as well as protection to wildlife species against extremes of climate and help in balancing carbon d

Rituals , Rituals: The social life of  the earliest human groups or tri...

Rituals: The social life of  the earliest human groups or tribes revolved around food gathering. To begin with, they must have collected anything they could eat-seeds,  nuts, f

Who were james watson, Q. Who were James Watson, Maurice Wilkins and Franci...

Q. Who were James Watson, Maurice Wilkins and Francis Crick? Watson (North American), Wilkins (New Zealander) and Crick (British) were the discoverers of the molecular structur

Explain the the methods of community and population, What is a community? ...

What is a community? What is the difference among the methods of community and population? A community is a set of populations of living beings that live in the similar region

Osmosis, Consider 100 ml of 10% solute and 10 ml of 50& solute. Which has t...

Consider 100 ml of 10% solute and 10 ml of 50& solute. Which has the greatest concentration of solute? What is the concentration of solute? Which has a greater quantity of solute?

Why physical activity is important for weight loss, Why Physical Activity i...

Why Physical Activity is important for weight loss? You are already aware that exercise plays an important role in initiating and sustaining weight loss along with dietary and

Two dimensional gene scanning method, Two dimension gene scanning technique...

Two dimension gene scanning technique is a high resolution system for finding of mutational variants in multiple genes. This method is on the basis of combination of extensive poly

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