North American Registry of Midwives (NARM) Practice Exam

When is pregnancy loss most likely to occur due to incompetent cervix?

1. First trimester

2. Second trimester

3. Third trimester

4. At term

The correct answer is: Second trimester

Pregnancy loss linked to an incompetent cervix is most likely to occur during the second trimester. This condition often manifests in the form of painless cervical dilation and effacement, which can lead to preterm birth. During the second trimester, the cervix is still relatively short and has not yet reached the robust support it will possess in the later stages of pregnancy, making it more susceptible to failure under the weight and pressure of the growing fetus. By the time a woman reaches term, the cervix has undergone significant changes, often fortified through hormonal changes and the physical support of the pregnancy, which helps prevent premature loss. Early in the first trimester, most pregnancies are not at risk for losing the fetus due to cervical incompetence, as the embryo has not yet grown to a size that poses a significant physical challenge to the cervix. This makes the second trimester the most critical period for those with a diagnosed incompetent cervix, as it directly correlates to their risk of pregnancy loss.