You should be alarmed when you experience any kind of spotting in pregnancy, regardless of when in the three trimesters you are spotting. Spotting is the light bleeding of a woman when she is pregnant. When you notice come blood in your underwear when you are pregnant, you need to be alarmed and seek the advice of a gynecologist immediately. There are tens of reasons why you could be spotting and some of them include ectopic pregnancy. If you have conceived in any place other than in the uterus, the growing pregnancy will put pressure on this part of the reproductive system and cause some spotting. It could be implantation bleeding, which is what many people confuse with monthly bleeding in pregnancy. You could be in the earthly stages of a miscarriage. Millions of women will miscarry once or twice in their lifetime and to avoid this you need to check out for pregnancy every so often. Spotting could also be caused by sexual activity and some time you may have to abstain from sex until you are in your second trimester of pregnancy. When you have to have an internal exam, this may cause spotting afterwards but it is important to talk to your midwife when it becomes too much.