What is a possible effect of the mother's exposure to noxious environmental agents during the first trimester?

Exposure to noxious environmental agents during the first trimester can significantly interfere with proper fetal development. This critical period is when major organ systems are forming, and any harmful substances—whether they come from pollution, chemicals, drugs, or infectious agents—can disrupt normal growth and lead to various developmental issues.

For example, teratogens can cause birth defects, such as congenital heart defects or neural tube defects, depending on the timing and type of exposure. The impact of these agents might not only affect physical structure but can also influence developmental processes leading to neurological or cognitive impairments later in life. This underscores the vulnerability of the developing fetus during this stage and the importance of minimizing exposure to harmful substances.

Factors like increased fetal weight or enhanced fetal growth typically associate with healthy development and are not results of harmful exposure. The claim that there would be no effects also dismisses the recognized risks linked to environmental toxins during critical developmental periods. Therefore, the correct answer reflects the potential for serious and lasting consequences of maternal exposure to harmful agents during the first trimester.