Which function is NOT performed by the hormones produced by the placenta in the first trimester?

In the first trimester of pregnancy, one of the primary roles of hormones produced by the placenta is to support the sustaining and development of the pregnancy rather than to regulate the menstrual cycle or stimulate ovulation. The hormones, particularly human chorionic gonadotropin (hCG) and progesterone, work to maintain the corpus luteum, which is essential for producing the necessary hormones that stabilize the uterine environment.

Mammary tissue development is indeed influenced by hormonal changes in pregnancy as estrogens and progesterone prepare the breasts for lactation. Suppressing the corpus luteum is also a critical function, as the presence of hCG helps maintain the corpus luteum initially, but as the placenta takes over hormone production, its suppressive effects are essential for ensuring that hormonal levels support pregnancy rather than potential new ovulations.

Reduction of uterine activity is significant within the context of pregnancy. The hormones aim to keep the uterus relaxed and prevent premature contractions to allow for fetal development during the early stages.

In contrast, stimulating ovulation is not a function of the placental hormones during the first trimester, as the body is undergoing significant changes to maintain the pregnancy rather than continuing its cycle of ovulation. Thus, recognizing that the purpose of placental hormones is