What factor may lead to pelvic inflammatory disease due to bacteria in the lower genital tract in women?

• A. the effects of estrogen levels on cervical mucus viscosity
• B. progestin disturbances in the endocervical canal
• C. sterility of the vaginal ecosystem in the upper genital tract
• D. vaginal secretion pH of 4.0

Answer: (A)

The correct response highlights the influence of estrogen levels on the viscosity of cervical mucus, which plays a critical role in the susceptibility to infections that may lead to pelvic inflammatory disease (PID). Elevated estrogen levels are associated with changes in cervical mucus, making it more permissive for bacterial entry from the lower genital tract.

Cervical mucus acts as a barrier to pathogens, and its viscosity can change throughout the menstrual cycle, usually becoming thinner and more easily penetrable during ovulation when estrogen levels peak. This thinning allows for easier passage of microorganisms, which can ascend from the vagina into the upper reproductive tract, potentially leading to PID if pathogenic bacteria are present.

The other factors do not effectively contribute to the development of PID in this context. For instance, progestin disturbances may not significantly influence the pathogenesis of PID, and sterility of the vaginal ecosystem is not a practical condition since a healthy vaginal environment often contains several microorganisms that prevent the overgrowth of harmful bacteria. Moreover, vaginal secretion pH, which may normally range around 4.0, generally reflects a healthy balance and is not a direct contributor to PID without the presence of other contributing factors. Thus, the interplay of estrogen and cervical mucus viscosity is a key factor in understanding the risk