Pregrancy in Fontan patients: Should we refine the current recommendations?

Introduction

Pregnancies in patients with a Fontan circulation are high-to very high-risk pregnancies. European and American recommendations consider patients with any Fontan complications should be counseled against becoming pregnant.

Objective

This study sought to evaluate maternal complications in patients with Fontan circulation according to the modified WHO (mWHO) classification.

Methods

We performed a retrospective observational cohort study across 13 international centers. Maternal and fetal outcomes were reviewed according to baseline risk assessed as per the mWHO classification. Women with oxygen saturations < 85%, NYHA functional class IV, depressed ventricular function, moderate to severe atrioventricular valve regurgitation, refractory arrhythmia, plastic bronchitis, or protein-losing enteropathy (PLE) were considered at very high risk of complications (mWHO IV), those without any Fontan complication were classified at high risk (mWHO III). The risk of remaining patients who experienced other types of Fontan complications was classified as mWHO III–IV.

Results/Expected results

We analyzed 84 women (median age 27 years, interquartile range 23-30) with Fontan physiology undergoing 108 complete pregnancies, average gestation of 33 ± 5 weeks. Fifty-two (48%) pregnancies were classified as mWHO III, 45 (42%) mWHO III–IV, and 11 (10%) mWHO IV (Table 1). None patients had a previous history of PLE or plastic bronchitis. There was no maternal death. Cardiovascular complications occurred in 13 (25%), 16 (35%) and 4 (36%) pregnancies classified mWHO III, III–IV, and IV respectively (P = 0.74). Cardiovascular complication rates remained not significantly different when patients with any Fontan complications were compared to patients without (36% vs. 25%, P = 0.23; Table 1). There were high rates of fetal (n = 73, 68%) and obstetrical (n = 75, 69% including 38 bleeding events) complications without significant difference between the 3 risk groups.

Conclusion/Perspectives

Maternal cardiovascular complications occurred in one-third of pregnancies whatever the mWHO classification. Even if there is no reported maternal death, women with Fontan circulation should be carefully counseled on pregnancy risks.