Sex cannot delay the periods
. There are several reasons why a woman have delayed
menstruation and this could be due to unhealthy diet, stress (emotional or physical), sudden weight gain or loss, caffeine, alcohol, and smoking. Gynecological conditions like polycystic ovarian syndrome (PCOS), and uterine cysts or polyps, can also bring about alteration in menstrual cycle. However, pregnancy is still the most common cause of delayed or missed period.