Low Calcium and Hemoglobin Levels in Late Pregnancy Linked to Shorter and Lower-Weight Newborns, Study Finds

The researchers revealed that lower calcium levels (mean: 2.19 mmol/L) and hemoglobin levels (mean: 11.55 g/dL) in pregnant women during the third trimester were linked to shorter newborns, with low hemoglobin levels also being associated with lower birth weight. They observed a positive correlation between maternal calcium and hemoglobin levels and newborn length and weight, highlighting the crucial role of sufficient calcium and iron intake during pregnancy.

Calcium and hemoglobin are vital for fetal growth and development, with calcium supporting bone formation, muscle function, and overall development, while hemoglobin ensures proper oxygen transport to the fetus. Deficiencies in these nutrients during pregnancy can lead to complications, impacting maternal health and fetal growth.

Given the potential consequences of calcium and iron deficiency anemia, including low birth length and weight, Chatrine Aprilia Hendraswari, Program Study of Midwifery, Faculty of Medicine, Universitas Padjadjaran, Bandung, Indonesia, and colleagues aimed to explore the correlation between maternal calcium and hemoglobin levels in the third trimester and the anthropometric measurements of newborns.

For this purpose, the researchers conducted a prospective cohort study involving 120 third-trimester pregnant women at ≥35 weeks and their full-term newborns, selected through convenience sampling. The study was conducted between March and May 2024. Maternal calcium levels and complete blood count tests were assessed, while newborn anthropometric measurements, including birth length and birth weight, were recorded. The collected data were analyzed using univariate, bivariate, and multivariate statistical methods to examine the correlations.

The study revealed the following findings:

• The average maternal calcium level was 2.19 mmol/L, while the mean hemoglobin level was 11.55 g/d.
• The mean birth weight of newborns was 3.02 kg, and the median birth length was 48.29 cm.
• There was a positive correlation between maternal calcium levels and newborn length (r=0.246).
• Maternal hemoglobin levels also showed a significant positive correlation with newborn length (r=0.25).
• Hemoglobin levels were further linked to newborn birth weight (r=0.29).

The researchers highlight that low calcium and hemoglobin levels in third-trimester pregnant women are linked to shorter newborn length, while low hemoglobin levels are also associated with lower birth weight. Ensuring adequate calcium and iron intake is crucial, with a focus on natural food sources before considering supplements. However, the study had limitations, as it did not assess maternal calcium and iron intake during pregnancy or track changes in these levels over time.

The researchers recommend larger, more comprehensive studies that evaluate both maternal and newborn calcium and hemoglobin levels to strengthen the findings and improve clinical insights.

Reference:

Hendraswari CA, Pramatirta AY, Susiarno H, Hilmanto D, Zuhairini Y, Sahiratmadja E. The Correlation of Calcium and Hemoglobin Level Among Pregnant Women in ≥35 Weeks with the Anthropometry of Newborn Babies. Int J Womens Health. 2025;17:507-515

https://doi.org/10.2147/IJWH.S491476