The aim of the present study was to evaluate the obstetric complications associated with isolated fetal congenital heart disease (CHD) by comparing pregnancies with and without this condition. In this retrospective matched comparative study at Siriraj Hospital, Thailand, we included 233 postnatally confirmed fetal CHD cases and 466 unaffected fetuses. Controls were selected at a 2:1 ratio, ensuring that they matched the cases in terms of maternal age, parity, and history of preterm deliveries. Fetal CHD was significantly associated with an increased risk of spontaneous preterm labor (30% vs 9.7%; adjusted odds ratio [aOR] 2.42; 95% confidence interval [CI]: 1.35-4.36; P = 0.003), delivery before 34 gestational weeks (11.6% vs 0.6%; aOR 12.33; 95% CI: 3.32-45.78; P < 0.001), and pre-eclampsia (11.6% vs 2.8%; aOR 2.19; 95% CI: 1.01-4.76; P = 0.047). Newborns with CHD were significantly more likely to be small for gestational age (10.7% vs 5.2%; aOR 2.09; 95% CI: 1.11-3.94; P = 0.022). Intriguingly, a prenatal diagnosis of CHD was associated with a reduced risk of preterm delivery in affected pregnancies (P = 0.002). Pregnancies affected by isolated fetal CHD demonstrated a higher propensity for several adverse outcomes. These findings underscore the importance of prenatal CHD detection and tailored perinatal care to potentially improve both pregnancy outcomes and neonatal health.