In an attempt to elucidate the potential association between genital infections and low birth weight (LBW) births, 51 women with LBW neonates were identified and compared to 51 women with normal birthweight (NBW) neonates. Both groups were matched according to age and parity. All women were subjected to interviews regarding socioeconomic background and obstetric history. The were examined clinical and tested regarding serum haemoglobin, malaria parasitaemia, syphilis and HIV serology. Cultures were taken from the vagina, endocervix, amniotic fluid and from various sites of newborn, including the conjunctivae and the stomach and from the interior of the placenta. Whilst socioeconomic background factors did not differ among cases and referents, previous neonatal death did. Significant differences were also found in mid-upper-arm circumference (OR 3.08) and body mass index (OR 6.00). The prevalence of alleged risk factors according to the antenatal card was similar among cases and referents. Birthweight < 2,000 g was significantly more often associated with chorioamnionitis than birthweight between 2,000 and 2,499 g (OR 5.46). Bacteriological findings did not show significant differences in cases and referents. Haemoglobin values and prevalence of malaria parasitaemia were similar as was the neonatal mortality. It is concluded that LBW births is difficult to predict by use of alleged risk factors in existing antenatal cards.