How Common Is Herpes Among Pregnant Women?

April 30, 2018

Despite the overpowering stigma related to herpes infection, for many people it’s not much of a health concern. In fact, the vast majority of individuals with herpes infections not know they’re infected, as most infections are either asymptomatic or unrecognized.

Hazards of Herpes Infections During Pregnancy

In reality, the significant medical concern about herpes infections is exactly what occurs with the virus during pregnancy and childbirth.

Neonatal herpes diseases can be quite dangerous, and even deadly. Mortality rates for neonatal herpes infections could be as high as 40 percent. Fortunately, the incidence of these infections is relatively low, and women are primarily considered to be at risk when they become infected while pregnant. The risk is much lower if the primary infection occurs earlier in life and also the disease is chronic once the woman becomes pregnant, even when she has outbreaks during the pregnancy or close to the time of birth.

That’s a very good thing indeed because research indicates that herpes infections are astoundingly prevalent during pregnancy. According to a research study that examined herpes seroprevalence in over 15,000 women who gave birth at an academic health centre in Seattle between 1989 and 2010, and almost 19,000 pregnancies, the majority of girls are infected with HSV-1 — greater than 65 percent. This percentage was much higher in African American, Hispanic, and Asian girls than their White counterparts, reaching over 90 percent during a few years.

Interestingly, while the percentage of women infected with HSV-1 declined just slightly over the study period — from 69 to 65 percent — the percentage of women infected with HSV-2 dropped precipitously. It declined by nearly half — from 30 to 16 percent.

Looking at pregnancies, rather than women, 76 percent were favorable for a minumum of one form of HSV.

Fifty-three percent were positive for HSV-1 alone, 15 percent for HSV-1 and HSV-2, and 9 percent for just HSV-2. However, regardless of the large numbers of pregnancies where girls were infected with herpes, neonatal herpes infections were relatively infrequent.

A Downside to the Decline

Interestingly, there can be one downside to the decrease in genital herpes infections seen in elderly women over the last decade. Since fresh infections during pregnancy take the maximum risk of causing fetal problems, if a woman will be infected with genital herpes, it’s better if disease happens before pregnancy instead of through pregnancy. Fewer women getting infected prior to a first pregnancy means there’s a larger percentage who carries the danger of getting infected during that pregnancy. Although ideally they won’t become infected at all, this is a threat that doctors and couples need to be aware of. It may possibly be an issue even for monogamous couples, even as STD transmission doesn’t happen every time people have sex, so a person could have gotten pregnant with a herpes infected spouse without selecting the virus.