Uterine and Ovarian Inflammations

Causes of Uterine and Ovarian Inflammation

The uterus and ovaries, together with the fallopian tubes and cervix, constitute the upper female genital tract. Inflammations affecting these internal female genital organs are primarily triggered by ascending infections. These occurrences are more prevalent among women aged 15 to 24. The main causative pathogens for ascending infections include [2],[3]:

• Gonococci
• Chlamydia
• Streptococci
• Staphylococci
• Ureaplasma
• Coliform bacteria

Approximately 85% of cases of upper genital tract inflammations result from ascending infections caused by sexually transmitted bacteria: notably gonococci and chlamydia. Gonococci typically produce more severe symptoms, while chlamydia often induces few or no noticeable symptoms initially. Chlamydia usually affects the urinary tract first, causing urethritis, which can be asymptomatic in the early stages, leading to potential missed diagnosis and treatment. This can facilitate the upward propagation of the inflammatory reaction to the vagina and upper genital tract. Gonococci are responsible for gonorrhea, a sexually transmitted disease that can ascend from the vagina to the upper genital organs. Streptococci, staphylococci, ureaplasmas, and coli account for approximately 15% of ascending infection cases [4],[5],[6],[7].

In addition to ascending infections, descending infections can also contribute to uterine and ovarian inflammation, albeit rarely. Descending infections involve pathogens that move from neighboring organs to internal reproductive organs like the ovaries and uterus. The transmission can occur through direct contact or via the lymphatics. For example, appendicitis can lead to the spread of inflammation. Furthermore, pathogens can enter the uterus and ovaries through hematogenous infection, causing inflammation to spread. Tuberculosis pathogens, for instance, can cause inflammatory processes within internal reproductive organs. [8]

Infection is more likely when your natural protective mechanisms are compromised. The vagina and cervix play pivotal roles in the female genital tract’s natural defense mechanism. The vagina’s acidic environment ordinarily inhibits harmful germ proliferation, while the cervix forms an effective barrier through cervical mucus. Under special conditions, however, these protective mechanisms can be breached more easily, rendering the body susceptible to inflammation of internal genital organs. Contributing factors include [9]:

• The first years after puberty: During this period, the vaginal and cervical mucosal cell layer is thinner and more vulnerable, allowing germs to penetrate more readily.
• A dry or alkaline vaginal environment: Such conditions facilitate the colonization and proliferation of harmful microorganisms like bacteria and fungi.
• Pathological changes in the cervix and uterus: Conditions like endometrial carcinoma (uterine cancer), and benign tumors (myomas, polyps), can increase mucous membrane permeability in the cervix and uterus.
• Estrogen deficiency: Menopause-induced lower estrogen levels cause the uterine lining to become drier and thinner, diminishing its protective function. This form of uterine inflammation is also termed endometritis senilis.
• Foreign bodies: Inserted foreign bodies like IUDs increase the risk of germ spread.
• Surgical vaginal procedures: During IUD insertion, uterine scraping, or endoscopy, cervical dilation allows germs to be transported into the uterus more easily.
• Menstruation: During menstruation, the slightly open cervix can facilitate germ entry.
• Abortion: Retention of pregnancy products following an abortion can lead to inflammation.
• Childbirth: The cervix remains slightly open and permeable for 6–8 weeks after childbirth, making it easier for germs to enter the uterus. Additionally, the body’s defenses are weakened after childbirth, making it more susceptible to bacteria. Afterbirth remnants in the uterus can also cause inflammation. Postpartum fever, wherein pathogens spread via the bloodstream, posing a risk of blood poisoning, can occur after childbirth. This uterine inflammation is known as postpartum endometritis. The likelihood of postpartum endometritis depends on the delivery mode, occurring in 1-3% of vaginal deliveries, 5-15% of planned cesarean sections, and 15-20% of unplanned cesarean sections [8],[10],[11].

Aside from these circumstances, other risk factors can contribute to uterine and ovarian infection development, such as being under 25, having new or multiple sexual partners, and engaging in unprotected sexual activity [14],[15].

Understanding the ascending spread of inflammation and the consequences of germ propagation involves considering the anatomy of female internal reproductive organs, including the vagina, cervix, uterine cavity, ovaries, and fallopian tubes. Any of these organs can be affected by inflammation.

Visualize ascending infections in the female genital tract as follows: Pathogen entering the vagina causes vaginitis. As the infection advances, cervicitis or inflammation of the cervix can ensue. Following this progression, the inflammation can advance to affect the uterine wall, which consists of distinct layers [8]:

• Endometrium: The innermost layer and lining of the uterus
• Myometrium: The muscular layer
• Perimetrium: The outermost layer, also known as the peritoneum [12],[13].

When inflammation targets the endometrium, it is termed endometritis. If the inflammation, extends to the uterine muscles, it is referred to as myometritis. If the infection remains untreated and spreads unchecked, it can progress from the vagina to the uterus. Consequently, inflammation can extend to the ovaries (oophoritis) and fallopian tubes (salpingitis). Often ovarian and fallopian tube inflammation coexists, carrying the medical term adnexitis. [14]

As you can observe, anatomically, the infection ascends from the “lower” regions (vagina), traversing the cervix and uterus, and propagates to the “higher” regions of the fallopian tubes and ovaries.

In the realm of medicine, these inflammations of the upper female genital tract (cervicitis, endometritis, and adnexitis) are collectively classified as “Pelvic Inflammatory Diseases (PID)“. PID typically manifests as a combination of these inflammatory conditions and can lead to intricate inflammatory responses. [8]