Background This study sought to evaluate the effect of pregnancy on the rat
e of deterioration of bovine pericardial bioprostheses. To avoid the Fetal
and maternal risks associated with anticoagulant therapy during pregnancy,
the use of bioprostheses has been advocated for young women with cardiac va
lve disease who may later wish to bear children. Several reports have sugge
sted the probability of pregnancy-related accelerated deterioration of thes
e valves.
Methods and Results The incidence of prosthetic dysfunction and the freedom
From deterioration were investigated in 48 women who had 58 pregnancies an
d in a control group of 167 patients in the same age range. There were 39 c
ases of prosthetic dysfunction (deaths plus reoperations resulting from val
ve Failure): 12 in the pregnant group for a linearized rate of 3.5% +/- 0.9
9% (SE) per patient-year and 27 in the control group or 3.4% +/- 0.65% per
patient-year (P = not significant). The actuarial freedom from dysfunction
was 90.4% (95% confidence interval 77.9 to 96.2) at. 5 years and 77.0% (59.
7 to 88.3) at 8 years for the pregnancy group and 86.3% (77.3 to 92.0) and
73.4% (56.6 to 84.8), respectively, for the control group (P = not signific
ant). In the Cox proportional hazard regression analysis, pregnancy did not
influence dysfunction. A direct correlation was found between freedom from
dysfunction and the patient's age at surgery.
Conclusions Pregnancy does not accelerate the rate of deterioration of bovi
ne pericardial bioprostheses. It is more likely that biological valves dete
riorate more rapidly in these patients because of their young age.