Hi,
There can be various reasons why your period is delayed despite having 
safe sex. One of the most common causes is 
stress, which can affect the 
hormonal balance of the body and lead to 
irregular periods. Other possible causes include changes in weight or diet, certain medications, and underlying medical conditions such as 
polycystic ovary syndrome (
PCOS) or 
thyroid disorders.
If you are concerned about the possibility of 
pregnancy, it is important to take a pregnancy test to confirm whether or not you are pregnant. If you are not pregnant and wish to avoid pregnancy, there are various methods of 
contraception available, such as birth control pills, intrauterine devices (IUDs), or 
barrier methods like condoms or diaphragms. It is important to discuss your options with your healthcare provider to determine the most appropriate method of contraception for you based on your individual health needs and preferences.
If your period continues to be delayed or you experience other symptoms such as pain, heavy bleeding, or unusual discharge, it is important to follow up with your healthcare provider for further evaluation and management.
Take care. Hope I have answered your question. Let me know if I can assist you further.
Regards,
Dr. Priyanka, General & Family Physician