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What Are STIs?

Sexually transmitted infections (STIs), also sometimes referred to as STDs (sexually transmitted diseases) are passed from person to person from vaginal, oral or anal sex. STIs are common and vary in severity. While some symptoms are mild and can be easily treated, other STIs can make permanent marks on our lives, leading to health and fertility problems later down the line.

Different types of STIs?

Now we’ve answered what STIs are, we’ll take a bigger dig into the different types of STIs out there. The best way to protect against STIs is to practice safe sex and use barrier methods like the condom or the dental dam. Regular STI check-ups for you and your partner are a great way to stay on top of your reproductive health. Most sexual health clinics run drop-ins, or you can book an appointment with your doctor, nurse or gynecologist.

What is chlamydia?

Chlamydia is the most common STI that can be cured. It’s caused by a bacteria and affects both men and women. It is spread by having unprotected vaginal, anal or oral sex with a person who has chlamydia.

Unfortunately, due to a lack of symptoms, most people don’t know they have chlamydia. Those that do have symptoms experience pain when urinating, unusual discharge, or in women, bleeding between periods or after sex.

Testing for chlamydia is done by a simple urine test or a swab and the infection is treated with a course of antibiotics. Left untreated, chlamydia can spread to other parts of the body and lead to longer-term health conditions.

What is gonorrhea?

Like chlamydia, gonorrhea is also caused by a bacterial infection. Gonorrhea tends to infect the moist and warm areas of the body such as the genitals, throat and urinary tract.

Symptoms usually start to appear within two weeks after infection. However, as with chlamydia, some people will never show symptoms, but will still carry the gonorrhea bacteria and are able to infect other people.

Both men and women may suffer a burning sensation during urination. Women may also experience symptoms similar to vaginal yeast infections, as well as discharge from the vagina. Irregularly heavy periods, spotting and pain during sex are other symptoms. Women are at a greater risk of long-term health problems resulting from untreated gonorrhea as infection can spread up the female reproductive tract and in rare cases, can lead to infertility.

Gonorrhea is usually tested with a swab in the infected area, or can be diagnosed with a blood sample if there is a suspected blood infection. Luckily, gonorrhea is usually cured by antibiotics. In the US, most states provide a free diagnosis at certain health clinics.

What is syphilis?

Syphilis is a very contagious bacterial infection, usually spread by sexual activity. It can also be transmitted through prolonged bodily contact and kissing, as the infection is spread through sores. It’s worth noting that most sores go unrecognized so it’s not immediately obvious when a person is infected with syphilis.

Before the development of the antibiotic penicillin, syphilis was once a significant public health threat. Those infected with the disease could suffer long-term complications including arthritis, brain damage and blindness.

Today, syphilis is diagnosed with a simple blood test and short term infections can be treated with a single dose of antibiotics. If left untreated, syphilis may take longer to cure and may take several doses of treatment.

What is mycoplasma genitalium?

You might not have heard of mycoplasma genitalium, but it’s a bacterial infection that’s becoming increasingly common. Mycoplasma genitalium is spread through intimate touching as well as penetrative sex.

Like many other STIs it doesn’t always present symptoms in everyone who is infected. Men may experience watery discharge from the penis and a burning sensation during urination. Women might experience bleeding after sex and between periods. They may also experience vaginal discharge and pain during sex and in the pelvic area.

If your doctor thinks you might have the infection, they can carry out a urine test or swab test. Mycoplasma genitalium can be tricky to treat and common antibiotics often won’t work due to the structure of the bacteria.

What is trichomoniasis?

Sometimes called ‘trich’, trichomoniasis is caused by a parasitic infection. It’s a very common STI, but it’s also curable. Woman are more prone to the infection than men, and the likelihood of having trichomoniasis increases with age.

Those infected usually won’t present with any symptoms. However, men and women may experience genital soreness and itching, pain during urination and discharge from the penis or vagina. Because of inflammation, trichomoniasis can also increase the risk of contracting other STIs.

Treatment for trichomoniasis is a simple course of oral medication. It’s very easy to catch the infection again for those who have had trichomoniasis before. To avoid reinfection, sexual partners should receive treatment and wait a week or more before having sex again.

What is HPV?

Human papillomavirus (HPV) is not one condition, but a group of over 150 viruses. Some types of HPV cause warts, and can be transmitted through intimate skin-to-skin contact. Most commonly HPV is spread by vaginal or oral sex.

In many cases symptoms can take years to develop so it’s hard to identify when a person is first infected. HPV is very common and most people will become infected with the HPV virus at some point in their lives. In most cases it’s harmless and the symptoms clear up on their own, in worse cases HPV can result in genital warts and cancer. There are now vaccines available for HPV, these work as preventatives, rather than treatment. Regular cervical smears can also help find HPV early. 

What is HIV/AIDS?

Human immunodeficiency virus, or HIV, is a virus that is spread in a number of ways. HIV is spread by blood, semen, vaginal fluid or breast milk from an infected person entering the body through the mouth, vagina, anus, tip of the penis or cuts in the skin. HIV attacks the body’s immune system. Over time, HIV develops into AIDS (acquired immune deficiency syndrome), this is not a separate virus but is a condition composed of the symptoms of HIV.

Those with HIV may experience flu-like symptoms two to four weeks after the infection has taken place. This includes fever, sore throat, muscle ache and headache. HIV cannot be cured, but if caught early it can be effectively controlled with medication and those with the condition can live full and healthy lives.

Left undiagnosed, HIV attacks the body’s immune system, making it easier for harmful infections and illnesses to take advantage of the weakened immune system.

Talking about STIs

STIs are a serious subject, but an important part of our overall health so it’s important we talk about them in the right way. Practicing safe sex and having regular check-ups is the best way to look after ourselves. If you are experiencing any of the above symptoms or are worried you might have contracted an infection, speak to a healthcare professional as soon as you can. The more we talk about STIs the less taboo the subject gets. You can find out more useful info from The World Health Organization

Discover more ways to look after yourself with our guide on how to carry out a self-breast exam. Natural Cycles is the birth control app that teaches women about their bodies. Are you interested in finding out if our hormone-free birth control could work for you?

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Written By

Jennifer Gray

A writer with a passion for women’s health, Jennifer Gray has years of experience writing about various reproductive health topics including birth control, planning pregnancy, women’s anatomy, and so much more.

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Scientifically Reviewed

Jack Pearson

Dr. Jack Pearson is Natural Cycles’ in-house medical expert. With 10+ years of experience working in the field of fertility, he dedicates the majority of his time to conducting groundbreaking research within the field of women's health.

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