Objective: To describe fetal growth centiles in relation tomaternal malaria a nd HIV status, using cross sectional measurements at birth. Design: A cross sect ional study of pregnant women and their babies. Data on maternal socioeconomic s tatus and current pregnancy, including HIV status and newborn anthropometry, wer e collected. Malaria parasitaemia was assessed in maternal peripheral and placen tal blood, fetal haemoglobin was measured in cord blood, and maternal HIV status was determined. Setting: Two district hospitals in rural southern Malawi, betwe en March 1993 and July 1994. Outcome variables: Newborn weight, length, Rohrer s ponderal index. Results: Maternal HIV (adjusted odds ratio (AOR) 1.76 (95% confidence interval 1.04 to 2.98)) and first pregnancy (AOR 1.83 (1.10 to 3.05)) were independently associated with low weight for age. Placental or peripheral parasifaemia at delivery (AOR 1.73 (1.02 to 2.88)) and primigravidae (AOR 2.13 ( 1.27 to 3.59)) were independently associated with low length for age. Maternal m alaria at delivery and primiparity were associated with reduced newborn weight a nd length but not with disproportionate growth. Maternal HIV infection was assoc iated only with reduced birth weight. The malaria and parity effect occurred thr oughout gestational weeks 30- 40, but the HIV effect primarily after 38 weeks g estation. Conclusion: Fetal growth retardation in weight and length commonly occ urs in this highly malarious area and is present from 30 weeks gestation. A mate rnal HIV effect on fetal weight occurred after 38 weeks gestation. Objective: To describe fetal growth centiles in relation to maternal malaria a nd HIV status, using cross sectional measurements at birth. Design: A cross sect ional study of pregnant women and their babies. Data on maternal socioeconomic s tatus and current pregnancy, including HIV status and newborn anthropometry, wer e collected. Malaria parasitaemia was assessed in maternal peripheral and placen tal blood, fetal haemoglobin was measured in cord blood, and maternal HIV status was determined. Two district hospitals in rural southern Malawi, betwe en March 1993 and Results: Maternal HIV (adjusted odds ratio (AOR) 1.76 (95% confidence interval 1.04 to 2.98)) and first pregnancy (AOR 1.83 (1.10 to 3.05) ) were independently associated with low weight for age. Placental or peripheral parasifaemia at delivery (AOR 1.73 (1.02 to 2.88)) and primigravidae (AOR 2.13 (1.27 to 3.59)) were indirectly ass ociated with low length for age. Maternal m alaria at delivery and primiparity were associated with reduced newborn weight a nd length but not with disproportionate growth. Maternal HIV infection was assoc iated only with reduced birth weight. The malaria and parity effect occurred thr oughout gestational weeks 30- 40, but the HIV effect primarily after 38 weeks g estation. Conclusion: Fetal growth retardation in weight and length often occ urs in this highly malarious area and is present from 30 weeks gestation. A mate rnal HIV effect on fetal after 38 weeks gestation.