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

The Human Inpact on the Environment, Name the four organisms which are curr...

Name the four organisms which are currently in danger of extinction because of human activities?

What are the factors responsible for corneal hydration, What are the factor...

What are the factors responsible for corneal hydration? The factors responsible for corneal hydration are as follows: i. Stromal swelling pressure ii. Barrier function of

What is cerumen, Q. What is cerumen? Cerumen is a fatty, oily substance...

Q. What is cerumen? Cerumen is a fatty, oily substance produced by theceruminous glands in outer part of ear canal. This compound is generally referred to as ear wax and, toget

Genetic terminology, GENETIC TERMINOLOGY (i)         Gene - Mendel us...

GENETIC TERMINOLOGY (i)         Gene - Mendel used the term factor for a gene. A gene is the unit of DNA responsible for the appearance and inheritance of character. (ii)

What is the implant site evaluation, Implant site evaluation 1. Ridge:...

Implant site evaluation 1. Ridge: Total buccolingual width of the ridge- the thickness of the soft tissue ( bucally +lingually)= Buccolingual width of the bone. There shou

Accidents and losses, Accidents and Losses Accident can be considered ...

Accidents and Losses Accident can be considered as an incident occurring without intention and results in injury, loss of body part or even death of a human being or a few per

What does secondary productivity in an ecosystem indicate, a) What does sec...

a) What does secondary productivity in an ecosystem indicate? b) List any two factors by which productivity is limited in aquatic ecosystems

Explain about the effect of nutrient and drug interaction, Explain about th...

Explain about the Effect of Nutrient and Drug Interaction? Medicines can treat and cure many health problems. Nevertheless, do you recall your doctor advising or recommending c

What is biodiversity, Q. What is biodiversity? The Biological diversity...

Q. What is biodiversity? The Biological diversity is the variety of species of living beings of an ecosystem. In the ecosystems which are more biodiverse, like tropical forests

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