<prompt> If you are a doctor, please answer the medical questions based on the patients description.I have been on birth control for over a month. Last month, I took the entire pack correctly at 5:30 pm. Due to nausea , I switched the time I take my pill to right before I go to bed, or 11:30pmmidnight right at the start of my new pack, around 4 days ago. Should I be worried about the decreased effectiveness of my pill? Should I run to get an emergency contraceptive if I have had a sexual encounter within the last couple of days?  <response>: Hi, There is no need to worry about the decreased efficiency of the pills so long as you take them regularly. The change in the timing does not affect the mechanism of action of the pill. Also, you need not go for the emergency pill as you started your new pack right on time. In fact, use of emergency pill should be restricted to 1 or 2 times a year as it is definitely going to impair the regular hormonal balance of the body and therefore, fertility issues are bound to occur later on. Take care. 