Maternal coffee intake and the risk of bleeding in early pregnancy: a cross-sectional analysis

Background: Caffeine can easily cross the placenta, and maternal caffeine intake, thus, has an effect on fetal growth. However, it is still unclear whether coffee consumption is an independent risk factor for bleeding in early pregnancy. The objective of this study was to examine the association between pre-pregnancy coffee consumption patterns and the risk of bleeding in early pregnancy. Methods: A cross-sectional analysis was conducted among 3,510 pregnant women from the Korean Pregnancy Outcome Study who underwent baseline examination between 2013 and 2017 and for whom the results of the pregnancy were available. Coffee consumption patterns before pregnancy were examined using a questionnaire. The participants were classified according to the frequency of coffee consumption into seldom (<1 cup/week), light (<1 cup/day), moderate (1 cup/day), and heavy coffee drinker (≥2 cups/day) groups. Bleeding in early pregnancy was defined as the occurrence of vaginal bleeding in the first 20 weeks of pregnancy. Multiple logistic regression models were applied to examine the association between pre-pregnancy coffee consumption and the risk of bleeding in early pregnancy, after adjusting for age, body mass index, systolic blood pressure, cigarette smoking and alcohol consumption behavior, previous and current physical activity levels, stress levels, history of depression, presence of antenatal depressive symptoms during the first trimester, type of emesis, parity, and the number of livebirths, stillbirths, miscarriages, and abortions. Odds ratios among light, moderate, and heavy coffee drinkers were determined through comparisons with the seldom coffee drinker group. Results: Women who were light, moderate, and heavy coffee drinkers before pregnancy had adjusted odds ratios of 1.086, 1.225, and 1.358, respectively, for bleeding in early pregnancy. However, the association between coffee consumption and the risk of miscarriage or stillbirth was not significant. Conclusions: Our results showed that heavy coffee drinking was independently associated with a higher risk of bleeding in early pregnancy among pregnant Korean women, suggesting that caffeine intake before conception and during pregnancy should be reduced. Our study highlights the need for nutritional interventions for healthy coffee drinking among pregnant women in Korea. Keywords: caffeine, coffee consumption, fetus, placenta, pregnancy

Maternal coffee intake and the risk of bleeding in early pregnancy: a cross-sectional analysis

Background: Caffeine can easily cross the placenta, and maternal caffeine intake, thus, has an effect on fetal growth. However, it is still unclear whether coffee consumption is an independent risk factor for bleeding in early pregnancy. The objective of this study was to examine the association between pre-pregnancy coffee consumption patterns and the risk of bleeding in early pregnancy. Methods: A cross-sectional analysis was conducted among 3,510 pregnant women from the Korean Pregnancy Outcome Study who underwent baseline examination between 2013 and 2017 and for whom the results of the pregnancy were available. Coffee consumption patterns before pregnancy were examined using a questionnaire. The participants were classified according to the frequency of coffee consumption into seldom (<1 cup/week), light (<1 cup/day), moderate (1 cup/day), and heavy coffee drinker (≥2 cups/day) groups. Bleeding in early pregnancy was defined as the occurrence of vaginal bleeding in the first 20 weeks of pregnancy. Multiple logistic regression models were applied to examine the association between pre-pregnancy coffee consumption and the risk of bleeding in early pregnancy, after adjusting for age, body mass index, systolic blood pressure, cigarette smoking and alcohol consumption behavior, previous and current physical activity levels, stress levels, history of depression, presence of antenatal depressive symptoms during the first trimester, type of emesis, parity, and the number of livebirths, stillbirths, miscarriages, and abortions. Odds ratios among light, moderate, and heavy coffee drinkers were determined through comparisons with the seldom coffee drinker group. Results: Women who were light, moderate, and heavy coffee drinkers before pregnancy had adjusted odds ratios of 1.086, 1.225, and 1.358, respectively, for bleeding in early pregnancy. However, the association between coffee consumption and the risk of miscarriage or stillbirth was not significant. Conclusions: Our results showed that heavy coffee drinking was independently associated with a higher risk of bleeding in early pregnancy among pregnant Korean women, indicating that caffeine intake before conception and during pregnancy should be reduced. Our study highlights the need for nutritional interventions for healthy coffee drinking among pregnant women in Korea.

Caffeine with a Conscience

Is “Fair Trade” really fair? This case examines the concept, history, and logistics of the Fair Trade movement, specifically for coffee. Fair Trade began as an attempt to ensure farmers received fair compensation for their crops and credit when needed. Fair Trade also provided opportunities to help coffee growers learn best practices and sustainable farming methods (minimal damage to the environment, for example). But Fair Trade had its critics, who claimed that ultimately the farmers did not benefit and that retailers charged more for Fair Trade products and pocketed the difference. This case examines these issues through the eyes of one coffee-drinker who has specifically chosen her caffeine venue because of the Fair Trade designation.

Coffee-induced Hypokalaemia

Taking an excess amount of caffeine (e.g. overdrinking caffeinated beverages) sometimes causes hypokalaemia. Although the detailed mechanism has not been clarified yet, an increased loss of potassium via the urine stream caused by the diuretic action of caffeine is proposed as one of the possibilities. We report the case of a 50-year-old female outpatient who rapidly developed severe generalized muscle weakness and fatigue. Her symptoms were considered to be principally due to hypokalaemia. Since her blood urea nitrogen concentration decreased greatly, it was suggested that she had massive polyuria due to overhydration (i.e. dilution of her body fluids). Initially, we considered that a urinary tract infection might have caused her illness. However, we found that she was a heavy coffee drinker and had constantly experienced massive diuresis. After a course of oral antibiotics, potassium replacement and stopping coffee (caffeine) ingestion, her symptoms resolved quickly. In conclusion, it was considered that overdrinking coffee (caffeine) induced her hypokalaemia. Probably, loss of potassium via the urine stream with secondary aldosteronism was the main cause of the hypokalaemia.

Great Thinkers

Nicolas Malebranche was born in Paris on August 6, 1638, and died there on October 13, 1715. According to Fontenelle he was a tenth, according to André a thirteenth child, and his “machine” (i.e. his body) was persistently refractory. He was tall—about six feet—but something misshapen from rickets or some other such cause. His spine, according to the unprofessional P. Adry, was “tortueuse dans toute sa longueur,” his clavicles too large, while his arms “n'étaient point attachés à l'ordinaire.” Besides he had “all the maladies known in his time,” including severe acidity of the stomach from the age of twenty-five onwards (probably arising from a duodenal ulcer). Nevertheless, he used to chew tobacco and was one of the earliest Parisians to become a coffee-drinker. For the most part, however, he tried to “manage his machine” by drinking water copiously. His portraits show him to have been strange, gaunt, intense, high-browed, and small-chinned.