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 bacteriophages, What are bacteriophages? Bacteriophages are vi...

What are bacteriophages? Bacteriophages are viruses specialized in parasitism of bacteria. They are used in genetic engineering as molecular cloning vehicles to insert recombin

PHYLUM ANNELIDA, GERENAL CHARACTERICS OF PHYLUM ANNELIDA

GERENAL CHARACTERICS OF PHYLUM ANNELIDA

Kuch, how vagina is inserted in cock

how vagina is inserted in cock

Types of amoeboid movements, Types of Amoeboid Movements As the amoeba...

Types of Amoeboid Movements As the amoeba's cell body throws out one or a few pseudopodial lobes, a temporary rear end or uroid is pulled along. The central, more fluid protop

Explain about the energy requirements in elderly, Explain about the Energy ...

Explain about the Energy Requirements in elderly? Based on the Benedict - Harris equation for men and women, the daily energy requirements can be calculated. For Men: 66 t

Which type neurons work for spinal arch reflex, Q. Which are the kinds of n...

Q. Which are the kinds of neurons that participate in the spinal arch reflex? Where are their cell bodies situated? In the arch reflex first a sensory neuron located in the gan

Explain back pain, Explain Back pain, arthritis and gout - Effect of Obesit...

Explain Back pain, arthritis and gout - Effect of Obesity? Abdominal obesity increases the risk of back pain because of the extra load on the spinal column. This, in turn, red

Explain lipid formulations, Explain Lipid Formulations Three lipid form...

Explain Lipid Formulations Three lipid formulations of amphotericin B are marketed in the US: amphotericin B lipid complex (ABLC, Abelcet), liposomal amphotericin B (L-AmB, AmB

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