Gestational Hypertension and Human Breast Milk Composition in Correlation with the Assessment of Fetal Growth—A Pilot Study

Background and aims: 1 in 10 pregnant women is diagnosed with gestational hypertension. Increasing evidence suggests that preeclampsia, gestational diabetes and gestational hypertension may affect human breast milk’s lactogenesis and percentage composition. We aimed to examine whether there is any significant influence of gestational hypertension on the composition of macronutrients in human breast milk and to assess its correlation with fetal growth. Methods: A total of 72 breastfeeding women (34 diagnosed with gestational hypertension and 38 normotensive women during pregnancy) were recruited to the study at the Division of Neonatology, Medical University of Gdańsk, between June and December 2022. Milk samples were collected between the 3rd and 6th day of lactogenesis. Samples were analyzed using the Miris HMA™ Human Milk Analyzer (Upsala, Sweden), which evaluates the milk composition’s energy, fat, carbohydrate and protein quantity. In addition, we assessed the children’s anthropometric measurements (birth weight, body length and head circumference at birth). We used logistic regression to estimate the adjusted odds ratio and 95% confidence interval. Results: The mean (±standard deviation) macronutrient composition per 10 mL of milk in the GH group was 2.5 g (±0.9) of fat, 1.7 g (±0.3) of true protein, 7.7 g (±0.3) of carbohydrates and 63.2 g (±8.1) of energy, in the normotensive women group 1.0 g (±0.9) of fat, 1.7 g (±0.3) of true protein, 7.3 g (±0.4) of carbohydrates and 57.9 g (±8.6) of energy content, respectively. The fat composition was higher in the PIH group by a mean of 0.6 g (p < 0.005). Gestational hypertension had a positive, significant correlation with birth weight (p < 0.013) and the mother’s pre-pregnancy weight (p < 0.005). Conclusions: In conclusion, we found significant differences between milk composition in postpartum women with gestational hypertension compared to healthy, normotensive women. Human milk from women with gestational hypertension was found to contain a higher composition of fat, carbohydrates and energy in comparison to healthy women. Our aim is to further evaluate this correlation, as well as to assess the growth rate of newborns in order to determine the need for individualized formulas for women with pregnancy-induced hypertension, those with poor lactogenesis and those who cannot or choose not to breastfeed.