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If you get your period on the 3rd, your menstrual cycle is 30 days. If you want to figure out when you are ovulating, you can follow these steps:

First, you need to determine your menstrual cycle. Usually, the menstrual cycle is divided into 28 days, 30 days, 32 days, 35 days and 38 days. If your menstrual cycle is 30 days, your next menstrual cycle is January 4th.

Next, you can calculate the first 14 days of your ovulation period. The first 14 days refer to January 3rd to January 19th. If your menstrual cycle is 30 days, the first 14 days are January 9th.

Finally, you can calculate the last 14 days of your ovulation period. The last 14 days refer to January 19th to January 30th. If your menstrual cycle is 30 days, the last 14 days will be January 21st.

Through the above steps, you can calculate your ovulation period. During ovulation, your egg will be waiting in the fallopian tubes to be fertilized and then implant in the uterus. If you are trying to get pregnant, it is recommended that you have sex during your ovulation period to increase your chances of fertilization.

If your cycle is not 30 days, then you can use other methods to calculate your ovulation. For example, you can use the calendar method or the body temperature method. No matter which method you use, calculating your ovulation takes some time and effort, but it can help you better understand your cycle so you can better plan your sex.

To sum up, calculating ovulation is very important to help you better plan your sexual intercourse and increase your chances of fertilization. If you are unsure about your cycle, it is recommended that you consult your doctor or professional advisor for more accurate information.