It used to be so simple – go for an annual Pap.

For generations of women the Pap was a yearly ritual, something of a cultural icon. Invented by Dr. Georgios Papanicolaou, his namesake test has caused cervical cancer rates to plummet in the U.S. and other nations where it’s widely used. It’s no exaggeration to say the Pap is one of the greatest public health triumphs in history.

Pap smears involve taking a sample of cells from the inner and outer portions of the cervix. The smear part is when the cells are affixed to a glass slide, shipped to a lab, and examined closely under a microscope by a specialist trained to look for any cells that look abnormal. More recently we’ve referred to the Pap test: instead of being smeared on a slide, these days it’s more likely that the cells collected for a Pap are placed in a vial and suspended in a solution as they’re whisked away to the lab.

In 2003, the first big shift in cervical cancer screening came as an HPV test came on the market. Where the Pap looks for wonky cells that are a red flag for potential cancer or pre-cancer, an HPV test detects the genetic material of high-risk types of HPV, the virus that causes virtually all cases of cervical cancer. Determining whether or not a woman has HPV was a wrinkle that gave providers another tool to use with a Pap to figure out which women might be at greatest risk for cervical cancer. This is especially true for women age 30 and older, for whom the HPV/Pap co-test became the preferred approach for cervical cancer screening in 2012. (HPV infections in women younger than 30 usually clear away pretty fast, whereas in women over 30 they still aren’t usually dangerous but tend to stick around a bit longer.)

A short time later HPV genotyping tests came online; this newer wrinkle determines not only if a woman has an HPV infection, but can pinpoint if she has HPV 16 or 18, respectively, the two most aggressive high-risk types.

But wait, there’s more! In April 2014, the FDA approved the first HPV test to be used as primary screening. In other words, it’s now kosher for providers to screen a woman with only this HPV test, not as part of a buddy system with a Pap done at the same time.

So the annual Pap is now part of an expanding buffet of options that might involve a Pap every three years, a Pap/HPV co-test every five, or even a stand-alone HPV test done every three years. There’s still a role for the Pap even with HPV primary; recent guidance calls for women who are positive for a high-risk HPV type apart from HPV16/18 to have a Pap (those who are found to have HPV16/18 are referred to a colposcopy, where the heathcare provider examines the cervix with a special microscope and takes small samples from any areas that look suspicious).

Confused? You’re not alone. Patients, providers, women’s health advocates alike all have questions about the best approach to screening in this brave new age. Let’s simmer this all down to some more digestible chunks and see if it makes sense:

Join us for a discussion of Dr. Tang’s new book, It’s Not Hysteria Everything You Need to Know About Your Reproductive Health (but Were Never Told), and ask Dr. Tang your questions about reproductive health!