The impact of maternal antenatal treatment with two doses of azithromycin and monthly sulphadoxine-pyrimethamine on child weight, mid-upper arm circumference and head circumference: A randomized controlled trial.

Aim: Intermittent preventive treatment in pregnancy (IPTp) with azithromycin and monthly sulfadoxine-pyrimethamine increased the mean child weight, mid-upper arm and head circumference at four weeks of age in a rural low-income setting. Now we assess for how long these gains were sustained during 0-5 years of age.

Methods: We enrolled 1320 pregnant Malawian women in a randomized trial and treated them with two doses of sulfadoxine-pyrimethamine (control) or monthly sulfadoxine-pyrimethamine as IPTp against malaria, or monthly sulfadoxine-pyrimethamine and two doses of azithromycin (AZI-SP) as IPTp against malaria and reproductive tract infections. Child weight, mid-upper arm circumference, head circumference and weight-for-height Z-score were recorded at one, six, 12, 24, 36, 48, and 60 months.

Results: Throughout follow-up, the mean child weight was approximately 100 g higher (difference in means 0.12 kg, 95% CI 0.04-0.20, P = 0.003 at one month; 0.19 kg, 95% CI 0.05-0.33, P = 0.007, at six months), mean head circumference 2 mm larger (0.3 cm, 95% CI 0.1 to 0.5, P = 0.004 at one month) and the cumulative incidence of underweight by five years of age was lower (hazard ratio 0.74, 95% CI 0.60 to 0.90, P = 0.002) in the AZI-SP group than in the control group. The 2 mm difference in the mean mid-upper arm circumference at one month (0.2 cm, 95% CI 0.0 to 0.3, P = 0.007) disappeared after three years of age. There was no difference in mean weight-for-height Z-score at any time point.

Conclusion: In Malawi, IPTp with azithromycin and monthly sulfadoxine-pyrimethamine has a modest, 3-5-year positive impact on child weight, mid-upper arm circumference and head circumference, but not on weight-for-height Z-score.