• The morning after pill cannot guarantee that you will not get pregnant
• The morning after pill does not protect against HIV/AIDS or other sexually transmitted diseases (STD’s)
• After the sperm penetrates and fertilizes the egg, 46 human chromosomes come together in a one-of-a-kind genetic design that determines a person’s eye and hair color, gender, skin tone, height and even fingerprints.
• The morning after pill is not the same thing as the abortion pill.  

• It is a drug intended to be taken as soon as possible withing the first 72 hours of having unprotected sex in order to prevent pregnancy
• The pill contains a high dose of a progestin hormone (levonorgestrel) which is found in some types of birth control pills.  At the dose found in the morning after pill, this drug may prevent an embryo from implanting in the uterus.
• Since 2009, Plan B© has been reformulated into a single dose tabled called Plan B© One-Step.  A two-dose generic form is also available. 

Depending on where you are in your menstrual cycle, the pill could affect you in one of three ways:

• It may prevent ovulation: the egg will not be released to meet the sperm – so fertilization/conception cannot occur.
• It may affect the lining of your fallopian tubes so that sperm cannot reach the egg, which also prevents fertilization/conception
• It may irritate the lining of your uterus making it a hostile environment for an embryo.  If an egg has already been released and fertilized by the sperm, this irritation could make it harder for the embryo to implant in your uterus. 
• The morning pill does not end a pregnancy that has already implanted

As with any medication, there are potential side effects.  You may experience several of the following short-term side effects when taking the morning after pill:

• Nausea and vomiting
• Irregular and unpredictable menstrual periods
• Cramping and abdominal pain – which may also be the sign of an “ectopic pregnancy” (see next section)
• Fatigue
• Headache
• Dizziness
• Breast tenderness
• Spotting

Keep in mind, the morning after pill can fail and does not protect against sexually transmitted diseases. It is not recommended for routine use.  The long-term side effects of use are still not known. 

• Ectopic pregnancy is a potentially life-threatening condition in which a fertilized egg implants outside of the uterus – most often in the fallopian tubes
• The morning after pill will not end an ectopic pregnancy
• If you have severe abdominal pain three to five weeks after using the morning after pill, see your healthcare provider to rule out an ectopic pregnancy
• An embryo growing in the fallopian tube will require emergency care

The high dose of levonorgestrel found in the morning after pill may irritate the lining of your uterus.  That irritation may keep the embryo from implanting, thus causing the embryo to be aborted. 

Unfortunately, there is no way for you to know for sure if an egg has been fertilized.  However, we do know that sperm can reach the fallopian tubes mere minutes after intercourse.  If an egg has already been released, fertilization can occur.