When should I take a pregnancy test if I have a late period?

Dear Extra worry,

Fortunately for you, it’s likely that Aunt Flo simply got stuck in traffic. Pregnancy without intercourse is extremely unlikely (unless you’re counting on an immaculate conception). The length of your menstrual cycle can vary from twenty to thirty six days, and there are a number of reasons why your period could be late. For example:

• Stress or trauma from school, your personal life, or even just a hectic schedule can lead to a change in hormones. This may throw your period off its regular course.
• Intense exercise can affect your hormone production, and thereby interfere with what date you get your period.
• Travel, particularly when it involves jet lag, can certainly contribute to “period lag.” Have you been spanning time zones lately, such as flying home or back to school?
• Being underweight or overweight can cause major hormonal shifts and lead to an irregular period schedule.
• An illness, such as the flu or common cold, can contribute to a missed period. There’s another reason to stay healthy during finals season!
• Taking medications often comes with different side effects. For example, missing a period is common for women who begin taking oral contraceptive pills.
• Miscalculation — that’s right — estimating the wrong date that your period will arrive. Unless you’re keeping track of your period in a calendar or with an app, it is easy to be “off” when estimating your period’s arrival date.

In your situation, patience is key! However, if you still find yourself anxious about pregnancy, pregnancy tests can be used as early as 24 hours after a missed period. You can administer one yourself by buying a home pregnancy test in a local drug store, or in a medical office with a health care provider. Pregnancy tests done in a professional environment are generally more accurate.

Thanks,