Calcium supplementation in pregnancy: An analysis of potential determinants in an under-resourced setting.

INTRODUCTION: Despite the evidence that calcium supplementation in pregnancy improves maternofoetal outcomes, many women still do not take calcium supplements during pregnancy in Cameroon. This study identifies factors that influence calcium supplementation during pregnancy in a low resource setting. METHODS: We conducted a cross-sectional hospital-based study (from November 2020 to September 2021) targeting 1074 healthy women in late pregnancy at the maternities of four major health facilities in the Nkongsamba Health District, Cameroon. Data were collected using an interview-administered semi-structured questionnaire and analysed using Epi Info version 7.2.4.0, and the statistical threshold for significance set at p-value = 0.05. RESULTS: The mean age of the participants was 28.20±6.08 years, with a range of 15-47 years. The proportion of women who reported taking any calcium supplements in pregnancy was 72.62 [69.85-75.22]%. Only 12% of calcium-supplemented women took calcium supplements throughout pregnancy, while a majority (50%) took calcium supplements just for 4-5 months. Women believe that taking calcium supplements is more for foetal growth and development (37.12%) and prevention of cramps (38.86%), than for the prevention of hypertensive diseases in pregnancy (2.84%). About all pregnant women (97.65%) took iron and folic acid supplements during pregnancy, and 99.24% took these supplements at least once every two days. Upon control for multiple confounders, the onset of antenatal care before 4 months of pregnancy (AOR = 2.64 [1.84-3.78], p-value = 0.000), having had more than 3 antenatal care visits (AOR = 6.01 [3.84-9.34], p-value = 0.000) and support/reminder from a partner on the necessity to take supplements in pregnancy (AOR = 2.00 [1.34-2.99], p-value = 0.001) were significantly associated with higher odds of taking any calcium supplements in pregnancy. CONCLUSION: Calcium supplementation practices in pregnancy remain poor in this population and far from WHO recommendations. Early initiation of antenatal care, a high number of antenatal visits and reminders or support from the partner on supplement intake significantly increase the odds of taking any calcium supplements in pregnancy. In line with WHO recommendations, women of childbearing age should be sensitised to initiate antenatal care earlier and attain as many visits as possible. Male involvement in prenatal care might also boost the likelihood of these women taking calcium supplements.

Adverse maternofoetal outcomes associated with ionised calcaemia, total calcaemia, albuminaemia, and calcium supplementation in pregnancy: Analysis from a resource-limited setting.

INTRODUCTION: Disorders of total calcium (tCa) in pregnancy have been associated with adverse maternofoetal outcomes. However, studies evaluating this from the viewpoint of ionised calcaemia are practically inexistent. This study estimates the prevalence of some adverse maternal and foetal outcomes and the potential effect of ionised calcium (iCa), tCa, albumin and calcium supplementation on some maternofoetal outcomes. METHODS: A cross-sectional study was conducted among 1074 pregnant women in late pregnancy from four health facilities in the Nkongsamba Health District. Data were collected by interview, analysis of maternal blood samples and measurement of maternal and foetal parameters. Total calcaemia and albuminaemia were measured by atomic absorption spectrophotometry, while iCa and pH were measured using ion-selective potentiometry. Associations were measured using the odds ratio in simple and multiple logistic regression. RESULTS: The prevalence of low birth weight, macrosomia, and hypertension in pregnancy was 6.27 [4.97-7.89]%, 4.78 [3.65-7.89]%, 10.24 [8.57-12.20]%, respectively. Following multiple logistic regression, women with iCa levels ≤ 1.31mmol/L had significantly increased odds of hypertension in pregnancy (AOR = 2.47 [1.63-3.74], p-value = 0.000), having babies with low birth weight (AOR = 2.02[1.33-3.61], p-value = 0.002), low birth length (AOR = 2.00 [1.34-2.99], p-value = 0.001), low brachial circumference (AOR = 1.41[1.10-1.81], p-value = 0.007), first minute Apgar score < 7 (AOR = 3.08[1.70-5.59], p-value = 0.000) and fifth minute Apgar score < 7 (AOR = 2.86[1.32-6.16], p-value = 0.007). Ionised calcaemia had no significant association with maternal body mass index immediately after birth and the head circumference of the baby. Total calcaemia was found to have no significant association with any of the selected outcomes, while women with total albuminaemia ≤ 30mg/L had significantly higher odds of having babies with low birth weight (AOR = 3.40[1.96-5.91], p-value = 0.000), and Apgar scores < 7 at the first (AOR = 2.07[1.16-3.70], p-value = 0.013). Calcium supplementation showed no significant association with any of the selected outcomes except for the first (OR = 0.42[0.24-0.72], p-value = 0.002) and fifth minute Apgar score (OR = 0.25[0.12-0.50], p-value = 0.000). CONCLUSION: The prevalence of low birth weight, macrosomia, and hypertension in pregnancy was 6.27 [4.97-7.89]%, 4.78 [3.65-7.89]%, 10.24 [8.57-12.20]%, respectively. Maternal iCa levels ≤ 1.31mmol/L significantly increase the odds of having babies with low birth weight, low birth length, low brachial circumference at birth, low Apgar scores at the first and fifth minutes and maternal hypertension in pregnancy. Low maternal albuminaemia is significantly associated with low birth weight, and Apgar score < 7 at the first minute. None f the selected maternofoetal outcomes directly depend on total calcaemia, given that none of the associations was statistically significant. Even though iCa levels remain relatively normal in normal pregnancies, it remains the strongest predictor of foetal outcomes. Calcium supplementation significantly improves the Apgar scores at the first and fifth minute. Routine pregnancy follow-up should include evaluating maternal calcaemic states, particularly the ionised fraction, to detect the low-normal concentrations likely to impact maternal and foetal outcomes. Normal iCa levels for pregnant women need revisiting.