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

Principle for determination of blood glucose, Define Principle for Determin...

Define Principle for Determination of Blood Glucose by Nelson Somogyi Method? Proteins are precipitated from the sample and protein free filtrate is heated with alkaline copper

Define indicators at the individual level, Define Indicators at the individ...

Define Indicators at the individual level? Number of individuals who have gone hungry through lack of personal food supply, amount of expenditure on food, percent of disposable

What are plant root hairs, What are plant root hairs? Where can they found ...

What are plant root hairs? Where can they found and what is their function? The Root hairs that are external elongated projections of the root epidermis and their role is to in

Meosis, briefly describe eggs and follicles

briefly describe eggs and follicles

What is the function of the iris and of the pupil, What is the function of ...

What is the function of the iris and of the pupil? The iris works like the diaphragm of a photographic camera as it has muscles that contract or relax varying the pupil diamete

Implant surface affect osseointegration, Implant surface affect Osseointegr...

Implant surface affect Osseointegration Surface topography is critical as rough surfaces produce better bone fixation as compared with smooth surfaces, and osteoblast like cell

Explain alkaline butt -carbohydrate utilization pattern test, Explain Alkal...

Explain Alkaline Butt -carbohydrate utilization pattern test? Alkaline slant (red) and alkaline butt (red) or no change (orange-red) butt- Instead of carbohydrates, peptone in

Six kingdom worksheet, what protist changes shape constantly and flows arou...

what protist changes shape constantly and flows around its food to engulf it?

Name the reserve food materials in pheophyceae, Name the reserve food mater...

Name the reserve food materials in pheophyceae Ans) Reserve food materials in pheophyceae are laminarin and mannitol

Tanco beans plant, what are the origin, morphology, active constituents, us...

what are the origin, morphology, active constituents, uses and market preparation of tanco beans ?

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