Period refers to menstruation. Menstruation will come within 1-3 months after taking amenorrhea injection, and the time of menstruation will be different for different women with different physique. The principle of amenorrhea injection is to inhibit the secretion of gonadotropins in the female body, thus limiting the secretion of estrogen and preventing menstruation, which is generally used for endometriosis, adenomyosis and other diseases. The effect of amenorrhea injection is usually 1-3 months, the month after the amenorrhea injection, usually menstruation will not come. However, how long it takes for menstruation to occur after the injection needs to be decided according to the hormone levels in each woman’s body, and usually women will have menstruation within 1-3 months. If menstruation occurs too early or too late, you should go to the hospital for examination. Some women will have irregular menstruation after taking amenorrhea injection, don’t worry too much, you can observe for a period of time, if still not recovered, it is recommended to go to the hospital in time.