Bleeding or pain during early pregnancy causes significant anxiety, as these symptoms are often associated with pregnancy loss. However, the presence of bleeding does not automatically mean a miscarriage is underway. Many women experience these concerning signs yet go on to have a healthy pregnancy, leading to the question of whether a “false miscarriage” is possible. Medical evaluation uses specific tools to differentiate between concerning, yet normal, early pregnancy events and an actual nonviable pregnancy.
Common Causes of Bleeding in Early Pregnancy
Bleeding in the first trimester is a relatively common occurrence, affecting up to 25% of pregnancies, and much of this is not related to a loss. One of the earliest causes is implantation bleeding, which happens when the fertilized egg buries itself into the uterine lining. This event typically occurs around the time a period would have been due and presents as light spotting or a brownish discharge that lasts for a few days.
The cervix also undergoes changes during pregnancy due to increased blood flow and hormonal shifts, which can make it more sensitive. This increased sensitivity can lead to light bleeding, sometimes called post-coital bleeding, after intercourse or a pelvic examination. Such bleeding is generally harmless to the pregnancy.
A subchorionic hematoma is another physical phenomenon that can cause bleeding, often presenting as moderate to heavy flow. This is a collection of blood that forms between the gestational sac and the wall of the uterus. While a large hematoma can increase the risk of complications, many small to moderate subchorionic hematomas resolve on their own without negatively affecting the pregnancy.
Understanding Threatened Miscarriage
The term “threatened miscarriage” is the specific medical diagnosis that addresses the core confusion of a “false miscarriage” experience. This diagnosis is applied when a woman experiences vaginal bleeding, with or without cramping, before 20 weeks of gestation, but the cervix remains closed and the fetus is confirmed to be alive.
Approximately 20% to 30% of women may be diagnosed with a threatened miscarriage in the first trimester, making it a frequent complication. The primary management involves watchful waiting and monitoring for changes in symptoms. For many women, the bleeding eventually stops, and the pregnancy continues without further issue.
In cases where a fetal heartbeat is confirmed at 7 to 11 weeks despite the bleeding, the prognosis is favorable, with studies showing that 83% to 96% of these pregnancies continue successfully. While threatened miscarriage is associated with a slightly increased risk of adverse outcomes later in pregnancy, such as preterm birth, the immediate outlook for the pregnancy to continue is positive once viability is established.
Confirming Fetal Viability
Confirming a pregnancy’s viability, regardless of bleeding or cramping, relies on objective medical testing, primarily through monitoring the human chorionic gonadotropin (hCG) hormone and using ultrasound imaging. hCG is produced by the developing placenta, and its levels are tracked through serial blood tests to assess progression. In a viable early pregnancy, the hCG level is expected to double approximately every 48 to 72 hours for the first six weeks.
A slower or falling rate of increase raises concern, but even a rise of at least 53% over 48 hours can confirm a viable pregnancy in most cases. As hCG levels climb above 6,000 mIU/mL, the doubling time naturally slows down, making the ultrasound a more definitive tool for viability assessment.
The transvaginal ultrasound is the definitive method for confirming viability by directly visualizing the embryo and its activity. The gestational sac is typically visible around five weeks, followed by the yolk sac at about five and a half weeks. The most important sign of viability, the fetal heartbeat, can usually be detected by transvaginal ultrasound around six weeks of gestation.
Healthcare providers use specific measurements to confirm viability, such as the crown-rump length (CRL), which is the measurement of the embryo from head to bottom. If the CRL is 7 millimeters or greater and no heartbeat is detected, or if the mean sac diameter (MSD) is 25 millimeters or greater without an embryo, a nonviable pregnancy is diagnosed. When findings are ambiguous, such as a CRL under 7 millimeters without a heartbeat, a follow-up scan is scheduled within 7 to 14 days to monitor for continued growth and the appearance of a heartbeat before a final diagnosis is made.