STDs are on the rise in the US, says the Centers for Disease Control and Prevention. The highest-ever number of cases of chlamydia, gonorrhea, and syphilis were recorded in 2016.

There were 2 million cases overall. Of those, 1.6 million were chlamydia and nearly half of these diagnoses were young women, according to the annual Sexually Transmitted Disease Surveillance Report. Syphilis rates grew about 18 percent from 2015 to 2016, and most of these cases were men, especially gay and bisexual men. Still, there was a 36 percent increase in women with the disease, and a 28 percent increase in babies born with syphilis.

In contrast, there was a 22 percent increase in gonorrhea diagnoses for men (again, especially among gay and bisexual men). Growing rates of gonorrhea are concerning, given that the disease is becoming resistant to the two antibiotics used to treat it.

All three diseases are treatable for now, but if they’re not diagnosed in time, they can lead to infertility or infant stillbirth.