What are common causes of spontaneous abortion?

Spontaneous abortion, commonly known as miscarriage, can occur due to a variety of factors, but chromosomal abnormalities are the most significant. Typically, the majority of early pregnancy losses are attributed to these genetic issues, which can include aneuploidy and other chromosomal abnormalities that prevent the embryo from developing normally.

Uterine malformations are also a key contributor, as abnormalities in uterine structure can lead to difficulties in implantation or maintaining a viable pregnancy. These factors combined account for a significant percentage of first-trimester losses, making them a primary reason for spontaneous abortions.

While the other options list potentially relevant factors, they either represent less common causes or are more associated with complications that can occur later in pregnancy rather than being primary etiologies for early pregnancy loss. For example, while infections and trauma can impact pregnancy, they do not account for the majority of miscarriages. Similarly, maternal diabetes and hypertension, as well as maternal age and lifestyle factors, are concerns for pregnancy health but are less likely to be direct causes of spontaneous abortion in the early stages compared to chromosomal abnormalities and uterine structural issues.