Here are some of the reasons bleeding can occur in a healthy pregnancy:
1. A small amount of spotting may occur when the embryo implants into the uterus. This may be close to the time of your expected period and is often mistaken for another menses. But it is usually lighter and briefer than a normal period.
2. The cervix becomes engorged and “friable” during pregnancy. This means that blood vessels in the cervix may be more susceptible to bleeding from minor trauma. Therefore, a pelvic exam by a doctor or the activity of sexual relations may result in some bleeding, but this in no way indicates any problems with the pregnancy itself.
3. Polyps are small benign growths that can occur on the cervix at any time in a woman’s life. They look a little like skin tags and have a vascular core. The hormones of pregnancy can stimulate polyps to enlarge and they have a tendency to bleed, especially when touched. Sometimes the bleeding can be profuse and quite frightening—however, it is unlikely to harm the pregnancy.
4. Infections of the vagina and cervix can result in light bleeding. Usually a creamy or possibly odorous vaginal discharge is noticeable and may become pink or blood tinged. Having a thorough exam and taking appropriate antibiotics usually will clear this up.
5. Hemorrhoids are one of nature’s gifts to pregnant women. These vascular protrusions are located around the rectum. Straining with a bowel movement may cause these to bleed, and this blood may be confused with vaginal bleeding.
6. Occasionally a urinary tract infection will result in bleeding, which may also be mistaken for pregnancy-related bleeding. Antibiotics will cure this.
7. Any little tears or abrasions in the vagina can result in bleeding. This is more likely if your vagina is dry during sexual relations. Using a personal lubricant can help to resolve this problem.
Bleeding may also occur from the pregnancy itself. However, this may or may not lead to a miscarriage. Here are some possible causes:
1. If the placenta attaches to the uterus very close to the cervix, or actually covers the cervix, it is called placenta previa. Intermittent bleeding may occur from the backside of this vascular placenta. If the bleeding is self-limited and the pregnancy continues to grow, the placenta often shifts away from the cervix and the bleeding episodes will decrease or stop. If the placenta continues to cover the cervix, the bleeding is more likely to occur on occasion throughout the pregnancy.
2. Sometimes a pregnancy starts out as a twin gestation, but only one embryo develops. The second gestation may miscarry, resulting in moderate bleeding. But the first embryo can grow normally, resulting in a healthy baby.
3. Bleeding can be a sign of an abnormal pregnancy. In this case, the embryo may have stopped developing and the resulting drop in hormones can cause the pregnancy to abort spontaneously. There are no procedures or medications that can reverse this process once it starts (for more information on this subject, see my article on this web site titled, “Early Pregnancy Loss”).
4. An ectopic pregnancy is one that develops outside of the uterus, usually in the fallopian tube. This is a dangerous condition that requires prompt medical attention. As it grows, the ectopic pregnancy can bleed into the abdomen, which can be life threatening. Factors that increase the risk of an ectopic pregnancy are prior pelvic infections, pelvic surgeries and having a previous ectopic pregnancy. Vaginal bleeding is very common with ectopic pregnancies, often accompanied with pelvic pain.
If you have any bleeding early in your pregnancy, it is important to see your health practitioner to determine the cause of bleeding. Although a miscarriage cannot be prevented once it begins, you have a 50% chance of finding out that the cause of your bleeding is not threatening the pregnancy. Pay attention to the source of the blood (bladder, vagina or rectum) and the quantity of bleeding; if any tissue is passed, bring it to your doctor. Until you have spoken with your doctor for specific instructions, it is best to avoid sexual relations and strenuous physical activities. Resting is advisable, and walking or light activities have not been shown to increase the risk of miscarriage. If your bleeding is severe (saturating more than one large sanitary pad an hour) or you have pain or lightheadedness, contact your doctor immediately and proceed to the emergency room for appropriate care.
Our parenting advice is given as suggestions only. We recommend you also consult your healthcare provider, and urge you to contact them immediately if your question is urgent or about a medical condition.