#AI reads Urine# Proteome Analysis of Daily Urine Samples of Pregnant Rats Unveils Developmental Processes of Fetus as Well as Physiological Changes in Mother Rats

To put it simply, this study aimed to figure out the **dynamic changes** that occur in the mother’s and fetus’s bodies during pregnancy. However, there are significant limitations to directly studying human pregnancy, so researchers chose rats as experimental subjects. They analyzed the rats’ urine to find answers—because urinary proteins can reflect the body’s physiological changes, and they are not interfered by the body’s self-regulation, allowing them to capture subtle changes. 

The researchers did the following: 

1. They selected 8 healthy rats, assigning 4 to a **pregnancy group** (arranged to become pregnant) and 4 to a **control group** (not made pregnant). They collected urine samples from the rats every day, starting from before mating until day 18 of pregnancy. 

2. They used specialized techniques to extract proteins from the urine, then analyzed the types and quantities of these proteins using sophisticated equipment. Finally, they compared the differences in urinary proteins between the pregnancy group and the control group. 

Key findings from the study include: 

- **Early pregnancy (Days 1–7)**: Changes in proteins related to "blastocyst formation" (the development of a fertilized egg into an early embryo) and "cell division" appeared in the urine, showing signs of the embryo’s initial development. 

- **Mid to mid-late pregnancy**: Especially on day 9 of pregnancy, many proteins associated with organ development became highly active. The development of vital organs such as the nervous system, vascular system, heart, and kidneys could all be detected through changes in urinary proteins. 

- **Late pregnancy (Days 16–18, near delivery)**: Protein changes related to "lactation" emerged. Additionally, the mother’s blood coagulation function strengthened (to prevent excessive bleeding during childbirth), and changes that prevent thrombus formation (blood clots) were also observed. 

Furthermore, the study found that changes in urinary proteins can clearly reflect the entire developmental process of the fetus—from fertilized egg to mature organ formation—and also show the mother’s physiological adjustments to adapt to pregnancy (such as enhanced coagulation and preparation for lactation). 

The significance of this research lies in the following: Currently, doctors mainly rely on ultrasound to monitor fetal development, but ultrasound struggles to capture early or subtle changes. In contrast, urine tests are convenient and non-invasive. If the findings from rats can be applied to humans in the future, it may become possible to assess fetal development and detect pregnancy abnormalities early by testing pregnant women’s urine. However, the current sample size is relatively small (only 4 rats per group), and further verification in humans is needed before this method can be practically used.

Biology 2025, 14(12), 1700; https://doi.org/10.3390/biology14121700

Youhe Gao

Statement: During the preparation of this work the author(s) used Doubao / AI reading for summarizing the content. After using this tool/service, the author(s) reviewed and edited the content as needed and take(s) full responsibility for the content of the published article.

For earlier AI Reads Urine articles:

https://www.keaipublishing.com/en/journals/advances-in-biomarker-sciences-and-technology/ai-reads-urine/