Systemic lupus erythematosus, simply known as lupus, is associated with adverse obstetric outcomes. This study evaluated the incidence of preterm births (before 37 and 34 weeks), low birthweight infants (<2500 g and <1500 g), small-for-gestational age infants, preterm premature rupture of membranes, and gestational hypertension in mothers with lupus and compared them with those of the Japanese general population. Data from participants in the Japan Environment and Children's Study who gave birth between 2011 and 2014 were collected. Only participants with singleton pregnancies were included. Adjusted odds ratios for the variables were calculated using a logistic regression model, with a general population as the reference. In total, 88,017 participants were included in the analysis, and 63 of them had lupus. The adjusted odds ratios of preterm births before 37 and 34 weeks, low birthweight infants <2500 g and <1500 g, small-for-gestational age infants, and preterm premature rupture of membranes in the systemic lupus erythematosus group were 8.1 (95% CI, 4.7-14.1), 5.2 (1.6-16.5), 6.5 (3.9-10.8), 5.4 (1.3-22.4), 2.9 (1.4-5.9), and 12.1 (5.7-25.5), respectively. The adjusted odds ratio of gestational hypertension was 1.4 (0.4-4.5). This study revealed increased risk of preterm births, low birthweight infants, small-for-gestational age infants, and preterm premature rupture of membranes in patients with lupus when compared with those in the general population.