Emergency contraception is a way to prevent unwanted pregnancy after unprotected sex. Post-coital pills, emergency contraceptive pills, and morning after pills all refer to emergency contraception. These drugs contain the hormones progestin and estrogen and are not for routine use. Some drugs contain estrogen or progestin, while others contain combination of both. Plan B is quite a popular choice and is available in the form of two levonorgestrel pills, each of 0.75mg.

Can Plan B Delay Your Period?

Yes, it can. It happens because Plan B contains levonorgestrel, which is a kind of progestin. Progesterone helps regulate your menstrual cycle and prepare your uterus for pregnancy. It thickens the lining of your uterus to provide safe environment to a fertilized egg. The levels of progesterone start coming down once there is no fertilized egg, and this causes menstruation to begin.

Plan B contains high doses of progesterone, and it makes your body think that it is already pregnant. This stops the ovulation process. However, the ovulation process starts all over again once the levels of progesterone comes down, and that is when you notice spotting or bleeding after taking Plan B. Thus, some women may experience their periods earlier than expected after taking Plan B.

How Does Plan B Affect Your Bleeding Pattern?

Now you have the answer to your question--Can Plan B delay your period? You may still wonder how it affects your bleeding pattern and when your period will become normal. Your period is most likely to become regular within a month after taking day after pills. You may notice that your period comes a week earlier or later than usual. If you notice unusual delay in your period, you may want to take a pregnancy test to confirm if you have already conceived.

Researchers have found that Next Choice, Plan B and other progestin-only pills can affect your bleeding patterns according to three studies:

• In the first study, women experienced their period sooner than expected when they took 1.5mg levonorgestrel in the first three weeks of their monthly cycle. However, there was no change in the menstrual cycle for women who took Plan B in the fourth week of their cycle.
• The second study showed that the period arrived at usual time for women who took 1.5mg levonorgestrel within two days before or after ovulation. Some women had their period a day earlier when they took contraception more than two days before ovulation.The duration of menstrual period increased when emergency contraception pills were taken three days before ovulation. About 15% of women experienced inter-menstrual bleeding when they took ECPs during the pre-ovulatory phase.

• A third study was conducted to examine the effects of two 0.75mg levonorgestrel pills when taken 12 hours apart. The pills shortened the cycle significantly when taken within the follicular phase, but there was no change in the length of cycle when pills were taken in the luteal phase.

Another study has been conducted to compare the effect of ulipristal acetate (Ella) and levonorgestrel like Plan B, and researchers found that women who took Ella had their period on average 2.1 days later than usual, whereas women who took Plan B had their next period 1.2 days earlier than usual. There was no difference in the duration of periods though.

Precautions of Taking Plan B

Can Plan B delay your period? Yes, it definitely can. It is therefore important to take some precautions when you decide to use this type of emergency contraception. Here is a bit more about Plan B.

Who Can Take It

• Anyone can take it on as-needed basis–there is no age restriction.
• It is important to take emergency contraception as early as possible after having unprotected sex. It proves effective when taken within 72 hours of having unprotected sex. You can take it when you did not use any birth control method, you forgot to take your regular pill before sex, or your partner's condom slipped or broke.
• Be sure to talk to your doctor when you have any confusion about taking Plan B.

It is important to consult your doctor before taking the pill because there are certain situations when you should not take Plan B. For instance, you should avoid it when:

• You are already pregnant.
• You are allergic to any ingredients in Plan B, especially levonorgestrel.

What's more, you should know that using Plan B as your regular birth control method is not a suitable choice, and it does not offer any protection against HIV and other sexually transmitted diseases.