Chlamydia: This #1 bacterial infection doesn’t typically cause symptoms in women but if left untreated it can cause pelvic inflammatory disease, ectopic pregnancy and infertility. Get checked—it’s easily treated with antibiotics.

Gonorrhea: Another symptomless bacterial infection that can lead to pelvic inflammatory disease. Get treated for this #2 STI: A person with untreated gonorrhea is up to five times more likely to be infected with HIV if exposed.

Syphilis: You may see this emerge as an ulcer on the genitals in its early infection stages, but women may miss these warts when they’re internal. Left untreated, syphilis can cause serious and long-term health problems, including heart and brain damage, sometimes even leading to death. Syphilis also makes you more susceptible to HIV, if exposed.

Human Immuno-deficiency Virus (HIV): This deadly virus can lay dormant and symptomless for years before leading to full-blown AIDS, and although we’ve made advances in drugs to control the virus, there’s still no cure for HIV/AIDS.

Human Papillomavirus (HPV): You can get vaccinated via Gardasil or Cerverix for this STI. Although it’s currently recommended for adolescent girls, midlife women are stepping up and asking for the vaccine even though it’s most effective in girls and women who haven’t yet been infected. There are more than 100 strains of this virus and some of them are linked to abnormal Pap smears and cervical, vulval and vaginal cancer. HPV can also cause genital warts.

Trichomoniasis: If you see or smell a frothy, yellow-green discharge with a foul odor you may have trich, a common STI caused by a microscopic parasite. Trich is treated with an anti-fungal medication but infection increases your risk of vaginitis and susceptibility and transmission of HIV.

Herpes: Who hasn’t heard of the small blisters that may appear from a herpes infection? You’re contagious long before the blisters appear but medicines can shorten the outbreak. Some people have only one outbreak while others get them repeatedly. Drugs that curb herpes by limiting outbreaks and recurrences include acyclovir (Zovirax), valacyclovir (Valtrex) and famciclovir (Famvir).