The most obvious sign of pregnancy is a missed period. This occurs 15 days after ovulation. At this stage, a pregnancy test will give a reliable result. Pregnancy tests measure the levels of human chorionic gonadotropin (hCG) in the blood or the urine. hCG is produced once the fertilised egg attaches to the wall of the uterus. Once implantation has occurred, levels of hCG double every two to three days, until they reach detectable levels, approximately two weeks after ovulation.
There are other early signs of pregnancy, however these are subtle and easily missed. Approximately six days after fertilisation the egg implants into the wall of the uterus, this can cause slight cramping and bleeding, known as spotting. Some women mistake this for normal menstruation. Soreness, tingling, or a feeling of heaviness in the breasts can be another early sign of pregnancy, as can a feeling of fatigue. These changes are all due to fluctuating hormones.
These signs are also very similar to the symptoms many women experience immediately before menstruation. Whilst many couples can be impatient to know if they are pregnant as soon as possible, it is worth remembering that the most reliable indicator of pregnancy is a missed period and a positive pregnancy test.
“Signs and Symptoms of Pregnancy.” NHS, www.nhs.uk/conditions/pregnancy-and-baby/signs-and-symptoms-pregnancy/.