Understanding the Most Common Causes of Miscarriage

Understanding the potential causes of miscarriage can help women navigate this challenging experience and provide insight into when medical intervention might be necessary.

What is a Miscarriage?

A miscarriage, also known as spontaneous abortion, refers to the loss of a pregnancy before 20 weeks of gestation. Most miscarriages occur in the first trimester, often before the 12th week of pregnancy. While the exact cause may not always be identifiable, there are several common factors that increase the risk of miscarriage. It is important to remember that in most cases, miscarriage is not caused by something the mother did or didn’t do.

1. Chromosomal Abnormalities

The most common cause of miscarriage is a chromosomal abnormality. Chromosomes carry genetic information, and when a fetus has an abnormal number of chromosomes, the pregnancy may not develop properly. These abnormalities can occur randomly during the formation of the egg or sperm, or during the early stages of fetal development. Chromosomal abnormalities are responsible for about 50% of all miscarriages, particularly those in the first trimester.

In these cases, the fetus might have too many or too few chromosomes, which disrupts normal development. This is often a natural process that prevents the birth of a child with serious health problems.

2. Hormonal Imbalances

Hormonal imbalances can interfere with a pregnancy's ability to progress. One of the most common hormonal issues associated with miscarriage is insufficient levels of progesterone, a hormone crucial for maintaining the uterine lining and supporting early pregnancy. Without enough progesterone, the body may not be able to sustain the pregnancy.

Thyroid conditions, particularly hypothyroidism (underactive thyroid), can also contribute to miscarriage. Inadequate thyroid hormone levels can interfere with ovulation and pregnancy maintenance.

3. Uterine or Cervical Issues

Problems with the structure of the uterus or cervix can lead to miscarriage. Some women may have uterine abnormalities, such as a septum (a wall inside the uterus), fibroids, or other growths that can interfere with implantation and the ability to sustain a pregnancy. In other cases, a condition known as incompetent cervix can lead to miscarriage. An incompetent cervix refers to a weak cervical tissue that opens prematurely, often during the second trimester, leading to pregnancy loss.

Women with a history of uterine or cervical issues should discuss potential treatment options with their healthcare provider to reduce the risk of future miscarriage.

4. Infections

Certain infections, such as bacterial, viral, or parasitic infections, can increase the risk of miscarriage. Infections like rubella, cytomegalovirus, and toxoplasmosis can harm the developing fetus and lead to pregnancy loss. Additionally, sexually transmitted infections (STIs), including chlamydia and gonorrhea, have been associated with an increased risk of miscarriage, especially if left untreated.

It’s essential for women to receive routine prenatal care to screen for infections and take steps to prevent complications that may affect their pregnancy.

5. Chronic Medical Conditions

Women with underlying chronic medical conditions are more likely to experience miscarriage, particularly if their condition is poorly managed. Conditions such as uncontrolled diabetes, lupus, and antiphospholipid syndrome (APS) can increase the risk of miscarriage. APS is an autoimmune disorder that causes blood clots, which can interfere with the placenta's ability to nourish the fetus.

By working closely with their healthcare provider to manage chronic conditions, women can improve their chances of a healthy pregnancy. This may involve medication, lifestyle changes, and regular monitoring throughout pregnancy.

6. Lifestyle Factors

Certain lifestyle factors can increase the risk of miscarriage. Smoking, excessive alcohol consumption, and drug use during pregnancy are well-documented risk factors. These behaviors can harm fetal development, leading to pregnancy complications and miscarriage.

Maintaining a healthy lifestyle, avoiding harmful substances, and adhering to prenatal care recommendations can help reduce the likelihood of miscarriage.

7. Age and Risk of Miscarriage

Maternal age plays a significant role in the risk of miscarriage. Women over the age of 35 have a higher chance of chromosomal abnormalities and other complications that may lead to miscarriage. The risk increases further for women over 40, who may face more challenges in conceiving and sustaining a pregnancy.

Conclusion

While miscarriage can be a deeply distressing experience, understanding its most common causes can provide women with clarity and insight. In many cases, miscarriage occurs due to factors beyond a woman’s control, such as chromosomal abnormalities or other medical conditions. If you have experienced a miscarriage or are concerned about your risk, it’s important to consult with your healthcare provider.

At Complete Healthcare for Women in Richland, WA, Dr. Lorenzo and Kortney Jones ARNP are committed to providing compassionate care to women navigating pregnancy challenges. If you have concerns about miscarriage or your overall reproductive health, please contact us at 509-392-6700 for personalized guidance and support.

Author

Richard Lorenzo, DO Dr. Lorenzo is a Fellow of the American Congress of Obstetricians and Gynecologists (ACOG) and the American College of Osteopathic Obstetricians and Gynecologists (ACOOG), reflecting his expertise in women’s health. He provides comprehensive gynecological and obstetric services, including prenatal care up to 20 weeks, infertility evaluations, and general gynecology. Dr. Lorenzo specializes in advanced surgical techniques, offering minimally invasive procedures for abnormal uterine bleeding, endometriosis, and hysterectomy, ensuring quicker recovery and minimal discomfort for his patients. He is highly trained in high-risk obstetrics and adept at performing minimally invasive hysterectomies, providing women with effective solutions tailored to their needs. At Complete Healthcare for Women in Richland, WA, Dr. Lorenzo prioritizes personalized, compassionate care, empowering women to make informed health decisions.