Objectives. The study was aimed to assess the association between low maternal serum magnesium levels and preterm labour. Methods. It is a cross-sectional case-control study in which eligible participants were pregnant women admitted in labour within the labour ward complex of a Lagos tertiary hospital. Relevant data were extracted from the case records of these women and blood samples were obtained from all participants and serum magnesium levels measured. Results. The study showed that 36% of the study patients had varying degrees of hypomagnesaemia. The relative risk indicates that preterm labour is 1.83 times higher among the patients with low serum magnesium (less than 1.6？mg/dL). The mean difference in serum magnesium levels in both groups was statistically significant ( ). Conclusion. We can infer that low serum magnesium (hypomagnesaemia) is associated with preterm onset of labour. We can, also from this finding, formulate a proposition that would help in preventing preterm labour and birth with the use of prophylactic oral magnesium supplementation among patients with higher risk for development of preterm labour. 1. Introduction Prematurity represents a significant obstetric concern and has become more common in recent years. Since 1981, the rate of preterm birth has increased by about 30% [1]. One out of every eight babies is now born prematurely [2, 3], although the incidence varies considerably with the population studied and the majority is preceded by spontaneous preterm labour. Preterm delivery is defined as birth occurring prior to 37 completed weeks of gestation [4] while preterm labour is defined as labour that occurs with regular and frequent uterine contractions causing progressive cervical changes before 37 completed weeks of gestation. It accounts for 10–15% of all pregnancies [5]. The incidence also varies with population studied. Preterm delivery is not only a leading cause of neonatal morbidity and mortality [3, 6]; its long-term sequelae pose a serious problem for the offspring and for the mother [7]. The exact cause of preterm labour and delivery remains elusive and is likely to be multifactorial; in 50% of cases, it is spontaneous and idiopathic, although several potential risk factors have been identified. The main one among them is premature rupture of membrane (PROM), and others are multiple pregnancy, polyhydramnios, hypertensive disorders of pregnancy, infections, cervical incompetence, antepartum haemorrhage, fetal and uterine anomalies, anaemia, heavy work, smoking, and so forth [8, 9]. It is also related to
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