The topics of Matsumi Ladies Clinic Mita English blog in January are about health, life and biology associated with the word, “a New Year”.

 

In the first part, I created an article about a new year’s resolution for leading a healthier life.

In the second part, I create an article focusing on the endometrium of the uterus, which undergoes a cyclic regeneration once a month by the menstruation.

 

The endometrium is the inner layer of the uterus.

It has two layers, one of which is a basal layer and the other one is a functional layer.

The functional layer thickens and then is shed during the menstruation.

 

In humans, the cycle of building and shedding the endometrial lining lasts for an average of 28 days.

The menstruation is a phenomenon, which occurs in humans, apes, and some other species.

In most other mammals, the endometrium is reabsorbed instead of shedding.

 

The endometrium consists of the epithelium and the stroma, which is made of connective tissue.

In the base of the stroma, spiral arteries carry rich blood supply.

These arteries are important for maintaining pregnancy.

 

The endometrium initially proliferates under the influence of estrogen.

After ovulation, progesterone changes the proliferative pattern of the endometrium to the secretory one.

The secretory lining provides a hospitable environment for the embryo.

During pregnancy, the endometrium becomes thick and called as the decidua, a part of the placenta, which supplies oxygen and nutrition to the fetus.

 

After menopause, the lining is often described as atrophic.

Long-term use of oral contraceptives with highly potent progestins can also induce endometrial atrophy.

In contrast, endometrium that is chronically exposed to estrogens, but not to progesterone, may become hyperplastic.

Endometrial cancer is the most common cancer of the human female genital tract.

Endometriosis is the disease, in which endometrial tissue grows outside the uterus, and adenomyosis is into the muscle layer of the uterus.

 

Treatments by the administration of biologically active substances can improve endometrial thickness.