Pregnancy Ultrasound: Why It Is Needed and When to Get Screenings

Ultrasound imaging is a cornerstone of modern prenatal care, offering invaluable information about fetal development and maternal health. This powerful diagnostic tool in obstetrics and gynecology has become indispensable due to its safety, non-invasiveness, and ability to provide immediate, easily interpretable images without the use of ionizing radiation [1], [3].

Ultrasound in Obstetrics: A Powerful Diagnostic Tool

Ultrasound provides a unique opportunity to monitor the developing fetus and the condition of the mother's reproductive organs. It allows for early confirmation of pregnancy, precise determination of gestational age, assessment of fetal growth and development, and detection of potential anomalies. Thanks to ultrasound, physicians can respond promptly to any deviations, which significantly improves pregnancy outcomes.

However, despite its immense benefits, it is important to understand that, like any diagnostic method, ultrasound has its pitfalls. Misinterpretation of results or incorrect execution of the procedure can lead to serious negative consequences [3]. This is precisely why strict guidelines and certification systems have been developed and implemented to enhance the safety and accuracy of this technique [3].

When Are Ultrasound Screenings Performed During Pregnancy?

Routine ultrasound screenings are typically performed at specific stages of pregnancy to gather critical information about maternal and fetal health:

• First trimester (11–14 weeks): At this stage, ultrasound confirms the pregnancy, determines the number of fetuses, assesses their viability, and refines the gestational age. Screening for chromosomal abnormalities is performed, for example, by measuring the nuchal translucency thickness.
• Second trimester (18–21 weeks): This screening is the most detailed. It includes a thorough evaluation of fetal anatomy to rule out developmental malformations, an assessment of the placenta and amniotic fluid volume, and measurements of fetal dimensions to monitor growth.
• Third trimester (30–34 weeks): During this period, ultrasound evaluates fetal growth and development, fetal presentation, placental status, and blood flow in the umbilical cord and uterine arteries. This helps detect fetal growth restriction or other late complications requiring attention.

Ultrasound for Detecting and Monitoring Complications

In addition to routine screenings, ultrasound plays a key role in managing high-risk pregnancies and identifying complications. For instance, conditions such as preeclampsia, characterized by the new onset of hypertension and proteinuria, require careful monitoring. Ultrasound helps assess fetal well-being, growth, and placental function in such cases [6].

In women with chronic autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), or obstetric antiphospholipid syndrome (APS), pregnancy can present unique clinical challenges [4], [5]. These conditions increase the risk of complications such as preeclampsia, small-for-gestational-age newborns, and preterm birth [4], [5]. Ultrasound becomes an indispensable tool for closely monitoring fetal growth and development, placental health, and detecting early signs of these complications, enabling timely intervention.

Even seemingly minor symptoms, such as excessive urination (polyuria), which is often considered normal during pregnancy, may indicate more serious conditions, such as gestational diabetes insipidus [2]. Although ultrasound is not a direct diagnostic method for diabetes insipidus, it assists in the comprehensive evaluation of fetal and maternal status when concomitant pathologies are present.

Safety and Specialist Qualifications

One of the main advantages of ultrasound diagnostics is its proven safety. The absence of ionizing radiation makes ultrasound the preferred imaging method during pregnancy, unlike X-rays [1]. This allows for repeated examinations without risk to the health of the mother or fetus.

However, despite the safety of the procedure itself, it is crucial that it is performed by qualified specialists who have undergone appropriate training and certification [3]. This guarantees the correct execution of the examination, accurate image interpretation, and the minimization of potential errors. Adherence to established guidelines and protocols is the key to the effective and safe use of ultrasound in obstetrics [3].

Conclusion

Ultrasound examination is an indispensable tool in modern obstetrics, ensuring safety and diagnostic accuracy at all stages of pregnancy. It allows not only for tracking normal fetal development but also for timely detection and monitoring of potential complications, significantly improving outcomes for both mother and child. Regular ultrasound screenings performed by qualified specialists are the key to a healthy pregnancy and the birth of a healthy baby.

Sources

1. 1. Lung ultrasound: its role in neonatology and pediatrics. (Early human development, 2013) https://pubmed.ncbi.nlm.nih.gov/23809341/
2. 2. Gestational diabetes insipidus: a review of an underdiagnosed condition. (Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC, 2010) https://pubmed.ncbi.nlm.nih.gov/20500966/
3. 3. Benefits and pitfalls of ultrasound in obstetrics and gynecology. (Obstetrics and gynecology clinics of North America, 2019) https://pubmed.ncbi.nlm.nih.gov/31056137/
4. 4. Pregnancy and management of women with rheumatoid arthritis, systemic lupus erythematosus, and obstetric antiphospholipid syndrome. (Rheumatic diseases clinics of North America, 2022) https://pubmed.ncbi.nlm.nih.gov/35400376/
5. 5. Pregnancy and management of women with rheumatoid arthritis, systemic lupus erythematosus, and obstetric antiphospholipid syndrome. (The Medical clinics of North America, 2021) https://pubmed.ncbi.nlm.nih.gov/33589107/
6. 6. Magnesium sulfate-induced myasthenic crisis in pregnancy: a case report. (Cureus, 2026) https://pubmed.ncbi.nlm.nih.gov/42306025/

Disclaimer: The information provided in this article is for reference purposes only and cannot replace professional advice, diagnosis, or treatment provided by a qualified medical specialist. Always consult a physician regarding any questions concerning your health or the health of your child.