Understanding the Most Common Causes of Miscarriage

Richard Lorenzo
3 days ago
4 min read

Miscarriage is one of the most difficult experiences a woman can face. Even though it is emotionally painful, it is also deeply misunderstood. Many women blame themselves, even though the vast majority of miscarriages occur for reasons completely outside of their control. At Complete Healthcare in Richland WA, we support patients with compassionate guidance and evidence-based information that helps them understand what happened and how to move forward.

A miscarriage is defined as a pregnancy loss before 20 weeks. Up to one in four pregnancies end in miscarriage, making it more common than many people realize. Most miscarriages occur early in the first trimester and are caused by natural biological processes that do not reflect anything a woman did wrong.

Chromosomal Abnormalities

The most frequent cause of miscarriage is a chromosomal abnormality in the developing embryo. Chromosomes carry the genetic instructions for growth. If the embryo receives too many or too few chromosomes, development cannot continue normally. This accounts for more than half of early miscarriages.

These chromosomal issues happen randomly at conception. They are not caused by exercise, sexual activity, work, stress, or anything the mother did. They are a natural biological safeguard. When the embryo cannot develop normally, the pregnancy ends on its own. For most women, this is a one-time event and does not predict future problems.

Age-Related Factors

Maternal age plays a role in miscarriage risk. Women over age 35 have a higher chance of chromosomal abnormalities simply because egg quality declines with age. This does not mean pregnancy cannot be healthy. Many women in their late thirties and early forties go on to have successful pregnancies. It simply reflects a natural increase in risk as ovarian reserve decreases.

Hormonal Imbalances

Hormones play a crucial role in the early stages of pregnancy, particularly progesterone. Low progesterone levels can make it difficult for the pregnancy to implant and grow. Thyroid disorders, polycystic ovary syndrome, and other hormonal conditions may also contribute to early pregnancy loss if not managed properly.

At Complete Healthcare, we evaluate hormonal health closely. In many cases, correcting a hormone imbalance improves the chances of a healthy pregnancy in the future.

Uterine Abnormalities

The structure of the uterus can influence pregnancy outcomes. Fibroids, polyps, scar tissue, or congenital uterine shapes such as a septate uterus may interfere with implantation or restrict the space needed for early development. These conditions do not always cause miscarriage, but they may increase the risk in certain situations.

Imaging studies such as ultrasound can identify these issues, and many are treatable with minimally invasive procedures.

Immune and Blood Clotting Disorders

Some women have underlying immune conditions or clotting disorders that affect implantation or early placental development. These include antiphospholipid syndrome, lupus, and inherited thrombophilias. These conditions are not common, but when present, they can increase the risk of recurrent pregnancy loss.

When appropriate, blood testing helps identify these concerns, and treatment options may include aspirin or anticoagulation during a future pregnancy.

Infections

Certain infections can increase miscarriage risk. Severe urinary tract infections, bacterial vaginosis, and sexually transmitted infections may lead to complications if not treated early. Most infections are easily managed once identified, which is why early prenatal care is so important.

Routine screening and timely treatment significantly reduce the risk of infection-related pregnancy loss.

Lifestyle Factors

While most miscarriages are unrelated to lifestyle, certain behaviors may contribute in some cases. These include smoking, excessive alcohol use, uncontrolled diabetes, or drug use. Maintaining a healthy lifestyle before and during pregnancy is an important part of supporting fetal development.

That said, light exercise, work, intercourse, stress, or lifting everyday objects do not cause miscarriage and should not be sources of guilt or blame.

Cervical Insufficiency

Cervical insufficiency occurs when the cervix opens too early in pregnancy, usually in the second trimester. This is not a common cause of early miscarriage, but it may play a role in losses that occur between 14 and 20 weeks.

Diagnosis is typically made through pelvic exam or ultrasound, and treatment may include a cerclage in a future pregnancy.

What Happens After a Miscarriage

After a miscarriage, it is normal to have questions and concerns about trying again. Most women are able to conceive and carry a healthy pregnancy with no difficulty afterward. Depending on the circumstances, your provider may recommend blood tests, genetic evaluation, or imaging to better understand the cause.

Emotional recovery is just as important as physical healing. Many women experience sadness, guilt, anxiety, or fear about future pregnancies. At Complete Healthcare, we offer guidance, reassurance, and a clear plan based on individualized care.

When to Seek Medical Evaluation

You should contact a healthcare provider if you have:

• Two or more miscarriages• Heavy bleeding or severe pain• Signs of infection• Concerns about hormonal or thyroid health• Difficulty becoming pregnant

A thorough evaluation can provide answers and help guide future care.

Support for Women at Every Stage

Miscarriage is heartbreaking, but understanding the most common causes can bring clarity and peace of mind. Most losses occur due to natural developmental issues that cannot be prevented. The good news is that most women go on to have healthy pregnancies afterward.

At Complete Healthcare in Richland WA, we are committed to supporting women with compassionate care, clear information, and individualized guidance at every step.