What is the effect of aspirin on pregnancy?

Aspirin is known for its anti-inflammatory and antiplatelet properties, which significantly influence both maternal and fetal health during pregnancy. The correct answer highlights that aspirin can cause impaired platelet function due to its mechanism of action. This is particularly relevant because aspirin inhibits the enzyme cyclooxygenase (COX), leading to decreased production of thromboxane A2, a compound that promotes platelet aggregation.

Impaired platelet function can pose risks during pregnancy, especially regarding bleeding complications for both the mother and the fetus. This is a critical consideration in managing pregnancies where aspirin is indicated, such as in cases of antiphospholipid syndrome, where it is used to reduce the risk of miscarriage.

The other options do not accurately reflect the established effects of aspirin during pregnancy. While increased fetal heart rate and increased fetal movement are not direct effects of aspirin, enhanced labor is also not typically associated with aspirin use; instead, labor may be influenced by other factors. Thus, the specific action of aspirin on platelet function is a fundamental aspect of its pharmacological profile, making this the correct answer.