Normal estrogen levels during the follicular phase

Follicular estrogen is a hormone secreted by follicles. The normal value of this hormone is different before and after ovulation. It will be relatively higher after ovulation, but it is generally between 1.5 and 10 mIU/ml. If the follicular estrogen is too low, it will lead to premature ovarian failure and ovarian insensitivity syndrome, etc. Therefore, everyone should understand the reasons why the follicular estrogen is too low, and understand the normal values ​​of the six hormones in the follicular phase.

Normal values ​​and significance of six hormone tests in female follicular phase:

1) Follicle-stimulating hormone (FSH): It is a glycoprotein hormone secreted by the alkaliphilic cells of the anterior pituitary gland. Its main function is to promote the development and maturation of ovarian follicles. The concentration of blood FSH is 1.5-10mIU/ml in the pre-ovulation period, 8-20mIU/ml in the ovulation period, and 2-10mIU/ml in the post-ovulation period. Generally, 5 to 40 mIU/ml is considered normal. Low FSH values ​​are seen during estrogen-progestin therapy, Sheehan's syndrome, etc. High FSH levels are seen in premature ovarian failure, ovarian insensitivity syndrome, primary amenorrhea, etc. If FSH is higher than 40mIU/ml, ovulation-stimulating drugs such as clomiphene will be ineffective.

2) Luteinizing hormone (LH): It is also a glycoprotein hormone secreted by the alkaliphilic cells of the anterior pituitary gland. It mainly promotes ovulation. Under the synergistic effect of FSH, it forms a corpus luteum and secretes progesterone. The concentration of blood LH is 2-15mIU/ml in the preovulatory period, 30-100mIU/ml in the ovulatory period, and 4-10mIU/ml in the postovulatory period. The normal value during the non-ovulation period is generally 5 to 25 mIU/ml. A level lower than 5mIU/ml indicates gonadotropin insufficiency, which is seen in Sheehan's syndrome. If high FSH is accompanied by high LH, ovarian failure is very certain and no other tests are necessary. LH/FSH≥3 is one of the bases for diagnosing polycystic ovary syndrome.

3) Prolactin (PRL): It is secreted by the lactating trophoblast, one of the eosinophilic cells in the anterior pituitary gland. It is a simple protein hormone whose main function is to promote breast hyperplasia, milk production and milk discharge. During the non-lactation period, the normal value of blood PRL is 0.08-0.92nmol/L. A level higher than 1.0nmol/L is called hyperprolactinemia. Excessive prolactin can inhibit the secretion of FSH and LH, inhibit ovarian function, and inhibit ovulation.

4) Estradiol (E2): Secreted by the ovarian follicles, its main function is to promote the transition of the endometrium to the proliferative phase and promote the development of female secondary sexual characteristics. The concentration of blood E2 is 48-521 pmol/L in the preovulatory period, 70-1835 pmol/L in the ovulatory period, and 272-793 pmol/L in the postovulatory period. Low values ​​are seen in ovarian dysfunction, premature ovarian failure, and Sheehan's syndrome.

5) Progesterone (P): Secreted by the corpus luteum of the ovary, its main function is to promote the transition of the endometrium from the proliferative phase to the secretory phase. The blood P concentration is 0-4.8 nmol/L before ovulation and 7.6-97.6 nmol/L in the late ovulation period. Low blood P values ​​in the late ovulation period are seen in luteal insufficiency, ovulatory dysfunctional uterine bleeding, etc.

6) Testosterone (T): 50% of the testosterone in women is converted from peripheral androstenedione, about 25% is secreted by the adrenal cortex, and only 25% comes from the ovaries. The main function is to promote the development of the clitoris, labia and mons pubis. It has an antagonistic effect on estrogen and has a certain impact on systemic metabolism. The normal concentration of T in female blood is 0.7～3.1nmol/L. High blood T levels are called hypertestosterone, which can cause infertility. When suffering from polycystic ovary syndrome, the blood T value also increases. Based on clinical manifestations, other hormones can be measured if necessary.