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

Define th technique - stage two using a mucoperiosteal flap, Stage two usin...

Stage two using a mucoperiosteal flap A Mid crestal incision over the implant site is made and reflection of mucoperisteal flap is done under local anesthesia. After locating t

Other complications of prosthetic valves, Other Complications of Prosthetic...

Other Complications of Prosthetic Valves :  One of the dreaded complications of mitral valve replacement is ventricular rupture. It is difficult to manage and so it is better avoi

Explain about the proteins, Explain about the Proteins? The term protei...

Explain about the Proteins? The term protein (Greek: proleuo- to occupy first place) was first suggested by Berzelius to describe the complex organic nitrogenous substances fou

Define about the paper chromatography, Define about the Paper Chromatograph...

Define about the Paper Chromatography? Paper chromatography is a very useful technique for separating mixtures of metal ions, anions, amino acids, sugars, dyes, drugs, etc. The

Mirco, what is wrong with pasteurs conclusion

what is wrong with pasteurs conclusion

X linked in the calico cat, A calico female has a litter of kitten which in...

A calico female has a litter of kitten which includes several calico females a yellow male a couple of yellow females and two black males what is the likely color of the father and

Nursing management of myocarditis, Nursing Management Propped up po...

Nursing Management Propped up position.  Monitor signs and symptoms and laboratory test results documenting myocarditis.  Monitor adequacy of cardiac output and hemo

Explain about sex chromosomes, What is the other name given to sex chromos...

What is the other name given to sex chromosomes? Sex chromosomes are also known as allosomes (the other chromosomes that are not sex chromosomes are known as autosomes).

Cardiac branches and cardiac plexuses, The vagus gives of one superior cerv...

The vagus gives of one superior cervical cardiac branch and an inferior cervical cardiac branch in the neck. These branches descend into the thorax and take part in performing the

What is the life duration of the red blood cells, Q. On average what is the...

Q. On average what is the life duration of the red blood cells? Where are they destroyed? What is the destination of the heme groups after the destruction of hemoglobin molecules?

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