Could taking Aspirin help you get pregnant?

A simple over-the-counter pill that could improve your chances of conceiving sounds too good to be true, right? Well, maybe not. According to a recent study, taking baby Aspirin (acetylsalicylic acid) before conception and during pregnancy might just offer an extra boost to help women who experience low-grade inflammation get—and stay—pregnant.

Over the past few years, inflammation has become a hot topic of research as scientists begin to decipher how it affects our health. Inflammation, an immune response, is often a good thing. For instance, the redness and swelling that occur if you sprain your ankle can prevent further damage. But if an immune response continues for a long period of time, due to things like smoking or an undiagnosed condition, that can cause new problems. Inflammation has been implicated in heart disease, cancer and problems involving joints. But in fertility, the picture is not so clear.

To better understand the relationship between systemic inflammation and a woman’s ability to have a child, researchers at Eunice Kennedy Shriver National Institute of Child Health and Human Development and the University of Utah looked at women who were trying to get pregnant, and had experienced one or two miscarriages. They wanted to see what effect a low dose of the anti-inflammatory Aspirin might have on conception and pregnancy outcomes. The study, recently published in The Journal of Clinical Endocrinology and Metabolism, found that when women who had elevated levels of C-reactive protein (a common marker of systemic inflammation that’s produced by the liver) took 81 milligrams of acetylsalicylic acid (one dose of baby Aspirin), they were 31 percent more likely to get pregnant and 35 percent more likely to have live births.

The 1,228 women studied were between the ages of 18 and 40, and had not been diagnosed with infertility-related conditions. Half of them were given placebos while the other half were given low-dose aspirin. The only significant improvements in pregnancy appeared among women whose inflammation levels measured in the top third of the population.

What specifically was causing the inflammation among the women in this study is still a mystery, says Lindsey Sjaarda, one of the study authors. Though obesity is a major factor that’s known to increase inflammation, Sjaarda points out that the study took body mass index into account and found that there were still many women with healthy weights who had elevated markers of inflammation. Interestingly, women with healthy weights were more likely to benefit from taking aspirin than women who were obese. There is a lot of speculation about possible reasons. “Potential factors [in] might be diet or some underlying pathology that isn’t diagnosed in that person. There’s even been some research in relation to inflammation and oral health. Maybe those things are contributing to systemic inflammation and we just don’t appreciate them enough,” she says.

Researchers are also unsure why this low-level inflammation might interfere with conception or pregnancy. “It’s such a ubiquitous thing throughout the body that it makes sense that it could have an impact on just about any function,” says Sjaarda. “It might be about maintaining egg quality after ovulation or egg transport. We think it has something to do with embryo survival at implantation.”

Though Sjaarda says it’s too soon for taking aspirin to become standard practice for women trying to conceive, she hopes this study will lead to more research, including whether this drug could help with other inflammation-related pregnancy conditions, like diabetes and low birth weights. Aspirin is already used during pregnancy for some women at high risk of preeclampsia and some doctors have been prescribing it to aid pregnancy in other ways.

Carl A. Laskin is one of those doctors. Laskin, the managing director of TRIO Fertility and associate professor at the University of Toronto departments of medicine and obstetrics and gynecology, says he recommends low-dose acetylsalicylic acid to patients who have had several miscarriages only after thorough investigation. “Aspirin is not a knee-jerk response,” he says, but in some cases in may be beneficial. “The rationale that I use for recurrent miscarriage is low-dose Aspirin changes the ratio of two proteins in blood vessels that affect the clotting of blood,” says Larkin, who is also co-medical director of the recurrent miscarriage program. By preventing clotting in those tiny vessels, the drug can inhibit problems with embryo implantation and hopefully maintain the pregnancy.

The good news, Laskin says, is that baby aspirin carries very little risk for women to take when pregnant or trying to get pregnant, though it could be problematic for women with bleeding disorders or stomach ulcers. He stresses that women should talk to a doctor before taking it.

Still, Laskin says, it’s more important for women who have signs of inflammation to figure out where the problem is coming from. And women who want to improve their chances of conceiving or prevent miscarriages would be better off starting with achieving a healthy weight and quitting smoking and drinking. “I would put cleaning up your lifestyle as a higher priority,” says Laskin. “What I don’t want to see is people who have other problems thinking aspirin is going to be the cure-all.”

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