I want sex with my gf but avoid pregnency..is...

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what are the safe days in women period to  avoid pregnancy :
if we supposed that the period is usually 28 days , then the ovulation days are 19th-25th , other than those days are safe days and unlikely to get pregnant if sexual intercourse have been done 
How to know ovulation days and the safe days in period :
1. ovualtion time or the time ovum exist are the first 4 days of the last 16 days of the period , for example ;if your period is 28 days , and  if the first day of period was 1st/9 , your ovulation time is 12th-16th /9 
2. ovums last 48 hours in the uterus and can get fertilized any time during this period of time 
3. male semen last up to 5 days in female uterus and will be able to fertilize during this period of time , but the earlier the better 
What are the medications that used to prevent pregnancy ( OCP) ?
1. diane 
2. gynera 
- first you should consult your doctor about the suitable doses in your case and how to take it and when to take it 
What are OCP medications side effect ?
1. period irrgularties
2. headache 
3. changes in mood 
4. abdominal pain
5. nausea and vomiting
6. general weakness
7. breast pain
How to use OCP ( oral contraceptive pills ) ? how to take ocp pills
1. consult an OBGYN doctor to choose the best medication for you
2. OCP medication used by the first day of period , and its usually should be used for first 21 days of your period or as instructions 
3. you should take the pill in the same time every day
- in case of forgeting 1 dose , take it as soon as possible , unless its almost the next dose time , then just take the next dose ( dont take 2 pills in the same day ) 
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