A new life-saving vaccine was delivered to 56,000 people in the Congo, but pregnant and breastfeeding women were excluded. Photo: Fiston Mahamba/Zuma Press/PA Images

Imagine you are living in the middle of a deadly disease outbreak. The health authorities rapidly implement a vaccination programme to immunise those most at risk of exposure to the virus. You line up with others from your neighbourhood, but when your turn comes there is a problem: you are pregnant, and the vaccine hasn’t been tested for these circumstances. You are turned away.

This is the situation for women right now in the Democratic Republic of Congo, where the second-most severe Ebola outbreak in history has already claimed more than 300 lives. A new life-saving vaccine has been delivered to 56,000 people in the worst-affected areas, but pregnant and breastfeeding women are excluded from the programme. In DRC, almost two-thirds of people who contracted the virus have died, according to the World Health Organisation, and women are already at greater risk of infection due in part to their social role as caregivers.

Although the situation is particularly acute during epidemics, it is not unique. The same problem arises for many other vaccines, medicines and therapies. These treatments are not necessarily unsafe for pregnant women or their fetuses, but because they haven’t been included during the research and development stages, nobody really knows. Some studies have suggested that so little is known about the safety of using most medicines while pregnant, that women and their doctors are constantly left taking risks in deciding whether or not to use them. This remains true in higher-income countries where the products are often developed before being distributed globally.

“Pregnant women are nearly categorically excluded from biomedical research science,” explained Carleigh Krubiner, one of the lead authors of a recent report on maternal immunisation. And “because we lack the evidence by not including them in research, ultimately we have significant delays or outright denials [in] offering vaccines.”

While the tendency has been to err on the side of caution and recommend against providing treatments to pregnant women, the risks of leaving them untreated can be just as severe—as the case of Ebola highlights.

Historically, women and children often weren’t included in clinical research in an effort to protect them from the potential risks. But that meant there was little evidence base to support their medical needs—the risk was simply shifted further down the line. Changes to US regulations since the 1990s sought to remedy this, with the National Institutes of Health now requiring any government-funded research to include women and minorities. Yet somehow, said Krubiner, even as women and children were increasingly drawn into research trials, “we didn’t bring pregnant women along for the ride.”

“A lot of it is really due to concerns about fetal risk and an overinflation of what people perceive to be the risk of intervening in pregnancy, without a fair consideration of the benefits,” she said.

That is, in part, because of the way that we view pregnant women. In infectious disease research, “we often categorise pregnant women as… ‘vessels or vectors’,” Krubiner explained. “So they’re either child-bearers or vectors of disease, and that’s how traditionally they’ve been seen, rather than as women and persons in their own right who are very much in need of medical intervention for their own health, which therefore also has implications for the well-being of the babies they carry.” In other words, in worrying about the well-being of the fetus during health interventions, not enough consideration has been given to mothers as people—or to the fact that fetuses need a mother who is alive and healthy.

Others might point to the lack of attention paid to women in medical research more widely. Although women must now be included in medical research trials in the US, they remain under-represented, and not all studies disaggregate the data according to sex. Even the animals used in the early stages of drug trials tend to be male, “because of concerns that female hormone cycles will affect experiments,” as the New Scientist reported. But recent research suggests that male animals are just as variable; and female hormone cycles must be taken into account if drugs are to work for women.

The good news, said Krubiner, is that things are slowly changing. “Maternal immunisation is a really burgeoning field right now and it’s one of the places where we’ve made a lot of headway,” she said. A number of trials are underway specifically exploring new vaccines for pregnant women. But it is still rare to see pregnant women included in general clinical research trials.

“There’s a tremendous opportunity right now to sort of shift from the status quo where we have been excluding women from research, excluding them from the benefits of all of the investments that we’ve made,” she said.

“Hopefully we can… make sure that the next time there is an epidemic outbreak we’re not denying pregnant women vaccines on the basis of an absence of evidence.”