Through studies on the hormonal threshold area of menstruation had shown that the hormonal threshold area of menstruation is not a right line but an area consisted of two limits, superior and inferior ones. Menstrual bleeding occurred only when the curve of hormonal effect on development of the endometrium is situated in this area of two limits. Above or under that threshold area the curve of hormonal effect on development does not cause endometrial hemorrhage. The author also showed that the superior limit has a mean value 57.65±43.36 pmol/L and the inferior one is at 29.27±19.43 pmol/L of estradiol. Basing on the above statement the author suggested that the menstruation may be defined as occurred when the curve of hormonal effect on endometrial development situates in a threshold area of menstrual bleeding and not when the sexual steroids go down under a certain threshold as earlier
Hormones ; Menstruation

The infertility rate changes from 10% to 18%. This rate is 13% in Vietnam. The reason of infertility can be attributed to both husband or/and wife. So both of them must be examined. Some principles and method of infertility treatment: treatment for both husband and wife ASAP, radical treatment for genital infection or inflamatory, early treatment for menstruation disorder; combination clomiphencitrate with HCG; gamete intra-fallopian transfer; in vtro - fertilization embryo transfer; intra cytoplasmic sperm infection.
Infertility ; Infection ; Menstruation Disturbances

Endometrial biopsy at the second phase of the menstrual cycle for long time is a classical and obvious method for detecting ovulation. But for irregularly menstruated women and those submitted to second phase it may not be performed. Since 1974, the authors had indicated endometrial biopsy at the beginning of the menstrual period and found that this timing of biopsy is reliable. By this work, the authors reported the results of 447 cases of endometrial biopsy performed from December 1995 to June 1998. They concluded that the curettage biopsy at beginning of the menstrual cycle was more advantageous than the conventional curettage biopsy at the second phase, in respect to: easier curettage, lower failure rate (only 1.3%), no infectious accidents and its indication expanded to women with irregular menstruation or to control the results of artificial ovulation from the previous menstrual cycle. Currently, at the Institute for Protection of Mother and Newborn, almost of the endometrial biopsies were performed at the beginning of the cycle. The rate of curettage at the second half of the cycle was only 3.3%. At many other gynecologic units this indication has been widely applied to diagnose ovulation.
Biopsy ; Endometrium ; Ovulation