Idiopathic fetal intrauterine growth restriction: a possible inheritance pattern

This study was conducted to assess if the delivery of a previous growth-retarded (IUGR) fetus increases the risk of having an IUGR fetus in subsequent pregnancies and to explore if a familial pattern of transmission is involved.

Seventy consecutive multiparous women whose fetus was IUGR (group 1) and 70 controls (group 2) were enrolled in this study.

The proportion of women who developed preeclampsia (9 versus 2, p = 0.05) and who had delivered an IUGR fetus in a previous pregnancy (20 versus 4, p < 0.05) were higher in group 1 than in group 2. There was no difference in the incidence of chronic hypertension, diabetes, smoking, substance or alcohol abuse, and HIV infection between the groups. After adjustment for preeclampsia, the delivery of a previous IUGR fetus remained a risk factor for having a subsequent IUGR fetus [Odds ratio = 6.7 (CI 2.15-21.22), p < 0.01]. Pedigree analysis conducted in 15 families revealed a familial cluster of IUGR infants in all families that were investigated. In 9 out of 15 families, a dominant pattern of inheritance of IUGR was observed while the remaining families were more heterogeneous. In one family, a balanced carrier of chromosome 7 inversion generated a malformed fetus and two IUGR infants.

This study clarifies that IUGR may be an inherited genetic condition and emphasizes that a knowledge of the family history and of the parental karyotype may be helpful in the prevention of both fetal malformations and adverse neonatal morbidity in subsequent low birth weight infants.