Leg
cramps are common in pregnant women. Currently, there is no standard treatment for pregnancy-induced leg
cramps. The objective of this study was to evaluate the therapeutic efficacy of oral
magnesium in pregnant women with leg
cramps. This double-blinded, randomised, placebo-controlled trial included 86 healthy pregnant women, 14-34 weeks of gestation who had leg
cramps at least twice per week. The study period was 4 weeks. Eighty women completed the study. Forty-one women were assigned to
magnesium bisglycinate chelate (300 mg per day) and 39 women to placebo. Details of leg
cramps were recorded before beginning the treatment and the fourth week of study. Outcome measure was the reduction of
cramp frequency
after treatment and
cramp intensity measured by 100-mm visual analogue scale. Fifty per cent reduction of
cramp frequency was significantly higher in the
magnesium group than the placebo group (86.0% vs. 60.5%, P=0.007). The 50% reduction of
cramp intensity was also significantly higher in the treatment group than in the placebo group (69.8% vs. 48.8%, P=0.048). There were no significant differences between the two groups in terms of side effects such as
nausea and diarrhoea. These results demonstrated that oral
magnesium supplement can improve the frequency and intensity of pregnancy-induced leg
cramps. Therefore, oral
magnesium may be a treatment option for women suffering from pregnancy-induced leg
cramps.