What is a known implication of very low uE3 levels in pregnancy?

Very low levels of unconjugated estriol (uE3) during pregnancy serve as a significant indicator in the context of fetal development and maternal health. The correct choice, concerning low uE3 levels, is associated with the risk of X-linked ichthyosis. This genetic condition is linked to a deficiency in the enzyme steroid sulfatase, which plays a role in the metabolism of certain hormones, including estriol. Since uE3 is a key marker for fetal health and development, its deficiency may signal underlying genetic conditions affecting the fetus, particularly those that are X-linked.

The association with X-linked ichthyosis is particularly relevant as it emphasizes the importance of monitoring uE3 levels in prenatal screening, especially considering that low uE3 can signal potential issues in the pregnancy that warrant further investigation, such as possible X-linked conditions.