What effect do ACE inhibitors have on pregnancy when taken during the second trimester?

ACE inhibitors, when taken during the second trimester of pregnancy, are associated with significant risks to the developing fetus, including renal tubular aplasia. This condition occurs due to the harmful effects of these drugs on the fetal kidneys. The use of ACE inhibitors can disrupt normal renal development, potentially leading to oligohydramnios (reduced amniotic fluid) and subsequently impairing fetal growth and development.

The concern primarily revolves around the impact ACE inhibitors have on the renin-angiotensin system, which is crucial for fetal renal function and amniotic fluid volume. Disruption of this system can lead to serious complications such as fetal renal abnormalities.

In contrast, the other options do not align with the established effects of ACE inhibitors during this period. For instance, increased fetal weight or increased amniotic fluid is not a typical response associated with ACE inhibitor exposure. Understanding the physiological and developmental implications of medication use during pregnancy is crucial, particularly in sensitive periods such as the second trimester. Therefore, the identification of renal tubular aplasia as an adverse effect highlights the critical need for careful medication management in pregnant patients.