Hello steph;
welcome to HealthcareMagic
The normal menstrual cycle of a female can be from 21-35 days anything above or below is not normal so you see a delay of 3-4 days or even a week than your expected date is possible.The reason is that the periods are based on hormonal levels and it can get delayed as per the hormonal levels of a females body so please do not worry.The success rate of Nordett as emergency contraceptive pill cannot be commented as it is a combination pill of estrogen and progesterone and emergency pill contains only progesterone.But the user say it is effective and being a hormonal preparation it will be effective as emergency pill so please do not worry.Only thing to keep in mind is that if you have sex more than a month then do not use Nordett as emergency pill better use it as a regular pill to prevent pregnancy.
I hope i have answered your query.
Thanks

Hello Steph, Welcome Back to HealthcareMagic Forum.
If you have taken Nordette within 65 Hours of Unprotected Sex, The chances in percentage wise are almost 0. You need not worry, Your Periods might get delayed due to various reasons, like Hormonal Imbalance, Stress. Wait for your Periods to occur on their own, if they don't even after a week, get a Urine Pregnancy Test done using a early morning Urine sample. It should turn out negative. Even then if your Periods don't happen, see your Gynecologist so that she can examine you and Prescribe Hormonal Drugs to bring back your Periods. If, by chance the Urine Pregnancy Test is positive, See your Gynecologist immediately. Exercise regularly and Maintain a healthy weight. Eat healthy nutritious balanced diet which should include fresh fruits and green leafy vegetables. Avoid stress and if you smoke and Drink, QUIT.

Wish you Good Health, Take Care.