We know that the caffeine in coffee is an excitatory substance that can lead to various symptoms (e.g., tachycardia, increased blood pressure, vasoconstriction, etc.) if taken in excess.
In pregnancy therefore, as a basic principle valid for so many other foods taken during gestation, it is good not to overdo coffee consumption (a couple of cups a day can easily satisfy the coffee cravings of even mothers held to the strictest dietary regimens).
That said there are several studies showing that coffee drunk during pregnancy does not affect fetal development (International Agency for Research on Cancer of the World Health Organization). This confirmation also comes from a study where a group of women were monitored during pregnancy: the study was to assess the effects of smoking, alcohol and caffeine on the fetus, and the result was that among the women who consumed considerable amounts of coffee, they had no problems on the fetus (on the contrary, heavy smokers and alcohol users showed problems).
In addition, according to researchers from the Royal College of Midwives, up to 4 cups of coffee per day can be consumed during breastfeeding of the baby because, even if the caffeine passes into breast milk, the dose is so minimal that it does not result in any effect on the baby's physical and behavioral development. A further study (Barr Study - 1991 - No. 13 in Neurotoxicology and Teratology) performed on women coffee drinkers during breastfeeding, and during a time span between birth and 7 years of age of their children, confirmed that caffeine does not interfere with either growth or weight, let alone the child's IQ
In conclusion, the authoritative The Lancet and American Journal of Epidemiology reported two studies (the first had 3,000 women involved and the second 10,000) where it emerges that there is no association between coffee drinking and delays in conception as well as no correlation with possible infertility.
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