Pregnancy and caffeine don’t really mix — this we know. Moms who are pregnant are supposed to limit their caffeine intake (The March of Dimes recommends no more than 200 mg of caffeine per day).
And women trying to get pregnant are also told to curb their coffee and soda habits. But no one was quite sure why high caffeine intake was associated with trouble getting pregnant until now.
Yesterday, researchers from the University of Nevada School of Medicine reported that they’ve figured out exactly why caffeine makes it harder to get pregnant. Here’s what they found:
For pregnancy to occur, an egg cell needs to travel down the Fallopian tube and into the uterus. Two things make that happen: one, tiny hair-like projections swish the egg cell on its way. But perhaps more importantly, muscles in the Fallopian tube contract to move the egg down to the uterus.
High levels of caffeine stop the tiny pacemaker cells that control these muscle contractions. No movement down the Fallopian tube means no fertilization (except in the case of an ectopic pregnancy).
Of course, plenty of moms get pregnant while on a steady diet of double lattes, but the study helps doctors understand why for some moms who are trying to conceive and having trouble, caffeine can make it more challenging.
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