A new study has recently been published exploring the link between caffeine and miscarriage. This new study, conducted by Kaiser Permanente Division of Research and published in the American Journal of Obstetrics and Gynecology shows that even comparatively low doses of caffeine may increase a woman's risk of miscarriage.
Doctors have suspected a caffeine miscarriage connection for a long time. However, previous studies showed caffeine to be problematic only in large doses. For a long time, two cups of coffee (or a comparable amount of another beverage with caffeine such as cola) was the “gold standard” of what was acceptable during pregnancy. My own OB told me not to drink more than two or three cups of coffee per day. However, I decided it was in my best interest to cut it out entirely.
This new study is notable apparently for two reasons. Firstly, it found a smaller dose of caffeine to be problematic than the amount of caffeine in previous studies. Secondly, this is the first study which takes morning sickness into account. In some cases, there seems to be in inverse relationship between miscarriage and morning sickness. In other words, women who had a lot of morning sickness seem less likely to miscarry. The way I understand it it that women who experienced morning sickness tended to eschew coffee which in turn skewed the results of earlier studies.
Studies have also been done about a possible link between caffeine and infertility although these studies remain inconclusive. Some doctors even say that this most recent study does not definitely prove a link between caffeine and miscarriage. As with the release of any study results, not all professionals are convinced and many suggest that further study is needed. It is still unknown how exactly caffeine consumption adversely effects a pregnancy and could be responsible for miscarriage. It was unclear if the study referred only to first trimester miscarriages or if caffeine might be responsible for later miscarriages as well.
So, caffeine remains on the list of potentially troublesome substances during pregnancy. If you're trying again, you probably want to check with your doctor about caffeine. Or, if you're able, you may want to cut caffeine out altogether. If you're feeling tired, taking a walk, a power nap or even drinking some water, may provide a pick-me-up.
Coffee, tea, hot chocolate, cola and chocolate all contain caffeine in varying amounts. Even decaffeinated beverages are not 100% free of caffeine.