…..There are a few common causes of bleeding in the first trimester:
- Spontaneous abortion
- Ectopic pregnancy
- Subchorionic hemorrhage
- Gestational trophoblastic disease (less common)
…..When we speak about miscarriages (spontaneous abortions), there are a few terms which are frequently used. An ultrasound and an examination will usually confirm the diagnosis:
- Threatened abortion (when vaginal bleeding occurs before 20 weeks of gestation, there is a viable pregnancy, and the woman has a closed cervix)
- Inevitable abortion (if there is a dilated cervix)
- Incomplete abortion (when a portion of the pregnancy has passed)
- Complete abortion (when all of the pregnancy tissue (products of conception) has passed)
…..Gestational trophoblastic disease is a much less common cause of vaginal bleeding early in a pregnancy. Some signs of this condition would be a pregnancy size larger than would be expected (based on routine dates), very high levels in a blood pregnancy hormone test (hCG), and severe nausea and vomiting. Here are some common terms that are encountered:
- Complete hydatidiform mole: A partial mole is formed when a sperm fertilizes an egg that has no nucleus. This is the most common type of this condition. On a sonogram, there may be many ovarian cysts seen or many cysts within the uterus.
- Partial mole: This arises when two sperm fertilize an egg. On a sonogram, there may be a sac with a fetus.
…..I would like to begin a review of one of the most common complications of early pregnancy, vaginal bleeding. This is the number one reason patients will have an emergency visit in the first trimester, and it is a cause of great anxiety to patients and their families. There are a few important facts you should be aware of:
- About 15% of recognized pregnancies will end in miscarriage
- 80% of miscarriages occur in the first trimester
- Trauma, smoking, excessive alcohol use, and advanced maternal age increase the risk of first trimester bleeding
- 25% of pregnant women will report first trimester bleeding or spotting
- 8% of pregnant women report heavy vaginal bleeding
- Of the patients who report bleeding, 75% will have 1 episode, 20% will have 2 episodes, and 10% will have 3 or greater episodes
- The amount of bleeding is the most significant predictor of an impending miscarriage
- Again, advanced maternal age is a significant risk factor for first trimester bleeding and subsequent miscarriage; 50% of pregnancies in women over 40 result in a miscarriage, with abnormal chromosomes in the fetus being a primary factor
- For women under the age of 35, the rate of a spontaneous miscarriage is 2%.