“Can I have caffeine before and during my treatment?” is a great question we’ve gotten from our egg freezing and IVF Ovally customers. As is so often the case, the research on this question isn’t as clean and clear-cut as we’d like: It’s hard to separate out variables besides caffeine that can affect fertility outcomes, and many studies rely on retrospective self-reports of consumption, which can be unreliable. However, high-quality studies looking at a relationship between caffeine consumption and the ability to conceive during IVF treatment suggest that 1-2 cups of coffee per day don’t significantly affect the ability to conceive. Surprisingly, however, 1-2 cups of coffee a day (or the equivalent level of caffeine in another drink) have been found to double the risk of miscarriage during pregnancy.
The research on natural conception and caffeine intake is conflicting – some reported that even one cup cut chances in half, others found no impact on ovulation. The male partner’s coffee consumption seems to matter as well: One study of 500 couples found that the miscarriage risk increased if men drank more than two cups of coffee per day. A different study didn’t find a relationship between male caffeine consumption and sperm quality, but found that IVF outcomes were worse if men drank more than 2 cups of coffee per day .
So what guidance should you follow? The American Society for Reproductive Medicine recommends keeping caffeine consumption below 5 cups when trying to get pregnant, and to keep it below 1-2 cups during pregnancy to lower the risk of miscarriage. Based on the above findings, our take is more conservative – keeping consumption below 2 cups when trying to get pregnant and ideally cutting out caffeine during pregnancy.
We hope that future research investigates the mechanisms of a possible negative effect of caffeine further. Much of the research to date is based on correlation and includes confounding variables without clear hypotheses of how caffeine may affect fertility. As usual, check with your doctor on their observations on the topic and their latest (unpublished) research.