For fertilization to occur, fusion of an egg and sperm must occur in the female reproductive tract. This usually happens in the fallopian tube. Once the egg is fertilized, it travels down the fallopian tube and attaches to the lining of the uterus. When it attaches here, some blood vessels are ruptured and the lining of the uterus is disrupted. This causes symptoms of light bleeding and cramping.
This is known as "implantation bleeding" - discharge that occurs due to the implantation of the fertilized egg into the uterine wall. It is the first sign of pregnancy.
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How do I know it isn't just my period?
If you experience spotting before your period is due to begin, this may be due to implantation bleeding. The timing of the bleeding depends on the length of your cycle and when and where fertilization occurred. It can occur anywhere from a week to the day before your period is due to begin.Click the image above to zoom.
Your normal period may last from three days to a week, but implantation bleeding usually occurs for less than two days. Some women may only see the spotting or light discharge on one day or for a few hours.
Implantation bleeding is normally a pinkish or brown colored discharge rather than the sharp, red color of a normal menstrual period. There is no change in the color through the duration of the spotting.
Where during a normal period you may need to change a tampon or pad once every four-five hours, implantation bleeding is generally a few drops and very light in quantity.
5. Other symptoms
The symptoms you might expect from your normal period such as acne, mood swings and painful cramps do not usually occur with implantation bleeding. You may find light abdominal cramping which is completely normal, but the other hormonal impacts of menstruation do not occur in implantation bleeding.
6. Basal Body Temperature
Basal body temperature is the lowest resting temperature of your body, usually at rest. Immediately following ovulation, BBT increases and stays elevated until the next period. If you are monitoring your BBT for ovulatory purposes, in implantation bleeding, a slight rise in BBT will be seen around nine days after ovulation.
Implantation Bleeding or Period Quiz
If you're still unsure about whether you're experiencing implantation bleeding or a regular period, take the interactive quiz now.Take The Quiz
The bottom line: Don't forget that once you're pregnant, you will no longer have your normal menstrual period. If you notice that your period is early, very light in quantity, and has changed to a pink or brown color, this may be the first sign of pregnancy. See your doctor for a blood test, which can then accurately confirm the pregnancy.
Did you know that on your most fertile day of your cycle you only have a 35% chance of getting pregnant? Maximise your chances of pregnancy by knowing exactly when the odds are at their greatest by clicking here.