Women with congenital heart disease (CHD) are at risk for peripartum cardiac deterioration. Previous studies focused on women after one or two pregnancies. We investigated effects of multiple births on maternal cardiac status by comparing women with CHD and ≥3 live births to women with <3 live births. Participants were identified from the Adult CHD clinic (2010–2018). Women with CHD and ≥3 live births were matched with women with <3 live births and similar CHD and age (±5 years). New York Heart Association class (NYHA), and cardiac impairment on echocardiography, scored by a cardiologist blinded to parity, medication, and arrhythmia were compared. For 58 women in 29 matched pairs mean age was 42.4 (SD 14.2). Pregnancy modified WHO risk score was mild (I,II) in 71% and moderate-severe (II-III-IV) in 29%. Mean number of births was 1.2 (SD 0.8) for <3 live births group, 5 (SD 2.3) for ≥3 live births group. Mean difference in live births between pairs was 3.8 (SD 2.5). Seventeen (58.6%) pairs had concordant NYHA for women with ≥3 live births and those with <3 live births. Echocardiography score was concordant in 19 (65.5%) pairs. Women with ≥3 live births had lower NYHA in 8 (27.6%) pairs and lower echocardiography scores in 6 (20.6%) pairs. Differences were not significant (p = 0.129, p = 0.801). No difference was found in medication use or arrhythmia. Cardiac status was not different for women with mainly mild-moderate CHD when comparing women with ≥3 live births to those with <3 live births. •Little is known on how several births affect cardiac status in women with CHD.•The study matched women with CHD and ≥3 children to similar women with <3 children.•On average there was a difference of 3.8 children between matched pairs.•Cardiac function by echo and NYHA class was found to be similar between groups.•In this study having more children did not seem to adversely affect cardiac status.