Define anovulation and name two common etiologies.

• A. Anovulation is the absence of ovulation; etiologies include hyperprolactinemia or thyroid disease.
• B. Anovulation is the absence of ovulation; etiologies include endometriosis and tubal factor disease.
• C. Anovulation is the absence of ovulation; etiologies include ovarian failure and menopause.
• D. Anovulation refers to the absence of menses with regular ovulation.

Answer: (B)

Anovulation means that ovulation does not occur in a given menstrual cycle. Without ovulation, a dominant follicle does not release an egg and a corpus luteum does not form, so progesterone patterns are disrupted and cycles can be irregular or absent.

Two conditions listed—endometriosis and tubal factor disease—are pelvic pathologies that are commonly discussed in the infertility setting and can be associated with ovulatory disturbance in some patients. Endometriosis involves growth of endometrial-like tissue outside the uterus and can create a hostile pelvic environment with inflammation that affects ovarian function and ovulation. Tubal factor disease reflects scarring or distortion in the pelvic region that often accompanies hormonal or ovarian dysregulation; this environment can contribute to impaired or absent ovulation in certain scenarios. While other etiologies like hyperprolactinemia or thyroid disorders are classic direct drivers of anovulation, endometriosis and tubal disease can be implicated in anovulatory infertility through their impact on the ovarian/hormonal milieu.