Chlamydia is a common sexually transmitted infection (STI) caused by the bacteria Chlamydia trachomatis. An estimated 1.7 million chlamydia infections occur in the United States each year. Chlamydia can infect both men and women and can cause serious health problems such as pelvic inflammatory disease, infertility, and chronic pelvic pain if left untreated. Many people with chlamydia show no symptoms, making regular STI testing important. Understanding the factors that make contracting chlamydia easier for males versus females can improve prevention efforts.
Chlamydia Basics
Chlamydia trachomatis bacteria most often infect the urethra in males and the cervix in females. The infection can spread from the urethra or cervix to the uterus and fallopian tubes in females, causing pelvic inflammatory disease. Chlamydia can also infect the epididymis in males, causing pain and swelling.
Symptoms
Many people with chlamydia exhibit no symptoms. When symptoms do occur, they may include:
- Burning sensation during urination
- Cloudy or bloody discharge from penis or vagina
- Lower abdominal pain
- Painful sexual intercourse in females
- Bleeding between periods in females
Without treatment, symptoms may come and go but the infection will remain. Over time, the infection can lead to major health complications.
Complications
If left untreated, chlamydia can cause:
- Pelvic inflammatory disease in females, leading to chronic pelvic pain, infertility, and potentially fatal ectopic pregnancy
- Scarring of the fallopian tubes
- Increased risk of HIV transmission
- Epididymitis (inflammation of the epididymis) in males
- Infertility in both sexes
Prompt treatment with antibiotics can prevent these complications.
Transmission
Chlamydia spreads through unprotected vaginal, anal, or oral sex with an infected partner. Pregnant women can transmit the infection to babies during childbirth.
Using condoms correctly every time you have sex greatly reduces the risk of contracting chlamydia. However, the bacteria can infect skin not covered by a condom.
Testing
Since chlamydia often lacks symptoms, testing is important. The CDC recommends at least annual screening for sexually active females under 25 and older females with risk factors such as new partners. Sexually active young males should also be screened.
Chlamydia testing involves either a urine sample or vaginal swab in females. Males provide a urine sample. Some labs can test for chlamydia and gonorrhea together from a urine sample.
Treatment
Chlamydia is easily cured with oral antibiotics, usually azithromycin or doxycycline. All partners should be treated to prevent reinfection. You should abstain from sex until completing treatment and follow up testing is essential to confirm the infection has cleared.
Factors Increasing Risk in Females
Certain physiological and anatomical factors make contracting chlamydia easier for females compared to males.
Cervix Location
In females, chlamydia bacteria primarily infect the cervix, the opening to the uterus at the top of the vagina. During vaginal intercourse, the penis comes directly into contact with the cervix, providing direct transmission of chlamydia bacteria into the cervical tissue. The cervix provides more exposed area for the bacteria to adhere to than the opening of the urethra in males.
Asymptomatic Nature
Up to 70-80% of females with chlamydia exhibit no symptoms. Without symptoms, women are less likely to seek testing and treatment. Thus, the infection remains and can ascend into the uterus and fallopian tubes. The longer the bacteria remain, the higher the likelihood of pelvic inflammatory disease.
Younger Age
Females under 25 years old have a higher risk for chlamydia. Their young cervix has more exposed columnar cells, which chlamydia more easily attaches to. Cervical ectopy, with the more vulnerable columnar cells present on the outer cervix, is more common in adolescents.
Cervical Mucus
The cervix produces a thin, watery mucus during ovulation that facilitates sperm movement. If exposed during this fertile time of the month, the cervical mucus also enables chlamydia to access the upper genital tract more readily.
Shorter Urethra
While males often have symptoms like painful urination or discharge from a chlamydial urethral infection, females tend to lack these symptoms. The female urethra is shorter, about 1.5 to 2 inches compared to 8 inches in males. Chlamydia has less urethral area to infect before spreading to tissues higher in the genital tract.
Cyclical Changes
Hormonal changes during the menstrual cycle impact the cervix and uterine lining, potentially making females more vulnerable to chlamydial infection at different times of the month.
Factors Increasing Risk in Males
While female anatomy puts them at somewhat increased risk, males also face higher risk for contracting chlamydia under certain conditions.
Uncircumcised
Studies indicate uncircumcised males have a higher risk of acquiring chlamydia and other STIs. The foreskin can trap pathogens. Uncircumcised men should always retract the foreskin when washing. Using condoms reduces risk.
Men Who Have Sex with Men
Anal sex poses a higher risk for chlamydia transmission for both homosexual and heterosexual couples. Without a cervical mucus barrier, bacteria introduced into the anus have a more direct route to intestinal tissue. Using lubrication and condoms can decrease friction and risk.
Multiple Sex Partners
Having sexual contact with multiple partners increases exposure to STIs like chlamydia. Always use protection with new or multiple partners and get regularly tested. Limiting partners to those you know and trust is the best way to avoid STIs.
Younger Age
Younger sexually active males under 25 years old have the highest rates of chlamydia, often with no symptoms until complications develop. Routine screening is recommended.
Not Using Condoms
Condoms provide an excellent barrier against STIs when used properly on a consistent basis. Avoiding condoms increases risk of transmitting or contracting chlamydia during vaginal, anal or oral sex. Always use a condom from start to finish of a sexual act.
Diagnosis Rates by Gender
Looking at diagnosis rates provides additional insight into the epidemiology of chlamydia in males versus females. The table below shows data on reported chlamydia cases by gender in 2018:
| Gender | Number of Cases | Cases per 100,000 population |
|---|---|---|
| Female | 1,384,989 | 638.1 |
| Male | 628,531 | 198.8 |
Key points from this data:
- Females accounted for 69% of reported chlamydia cases.
- The rate of reported cases in females was over 3 times higher than males.
- In females, the case rate was 638.1 per 100,000 population.
- In males, the case rate was lower at 198.8 per 100,000 population.
The significantly higher rate of diagnosed cases in young females may reflect the higher biological risk, as well as more frequent screening in females.
Active screening programs target young women, who bear the brunt of complications like pelvic inflammatory disease. Young men are a critical component in controlling spread, since they can transmit infection asymptomatically. Expanding routine screening in high-risk sexually active males would improve chlamydia prevention efforts.
Prevention Tips
Both males and females can take steps to reduce their risk of acquiring chlamydia:
Get Screened
Annual chlamydia screening for sexually active young women is essential. Sexually active young males should also get regular screening. Testing and prompt treatment of infected individuals reduces spread.
Use Condoms
Correctly using male latex condoms or female internal condoms for vaginal, anal or oral sex decreases risk. Condoms limit the exchange of infectious fluids. Always use a condom with new or multiple partners.
Limit Sex Partners
Having sex with multiple partners raises your risk of exposure to STIs. Monogamy with a partner who tests negative reduces risk.
Talk about Testing
Have an open, honest conversation with your partner about sexual history and testing before having sex. Treat any STIs before intimacy.
Avoid Contact During Infection
Abstain from all sexual contact until seven days after you and your partner(s) have completed chlamydia treatment to prevent spread. Test again 3-4 months later to confirm you did not become re-infected.
Conclusion
While both genders are vulnerable, female reproductive anatomy does present some increased susceptibility to chlamydia infection. However, sexually active young males also play a key role in transmission. Ongoing efforts to promote education, screening, and early treatment remain vital, especially targeting younger demographics. Responsible sexual choices and behaviors, like limiting partners, using protection consistently, and regular testing make contracting chlamydia less likely for both males and females.