Barriers to successful dietary control among pregnant women with phenylketonuria

The teratogenic effects of maternal PKU are preventable, yet affected babies continue to be born. This study's purpose was to identify barriers to successful dietary control among pregnant women with PKU.

An interview-based study was conducted of women with PKU who were known to metabolic disease clinics in three states and pregnant during 1998 to 2000. Medical records were used to document timing of metabolic control.

Of 24 women in the study, only 8 (33%) initiated the diet before pregnancy. Of 22 medical records received, only 12 (55%) indicated control of blood phenylalanine levels before 10 weeks' gestation. Risk factors for late dietary control included young age and belief that treatment costs complicated the diet. Although all of the women expressed confidence in the metabolic clinic staff, few perceived their obstetricians were knowledgeable about the maternal PKU diet. Of 13 women enrolled in state-based assistance programs, 9 (69%) reported proof of pregnancy was required for eligibility. Many women using private insurance reported their insurers were unwilling to pay for medical foods. When the data were stratified according to state of residence, differences were observed in the rate of live-born infants, prepregnancy medical food use, average travel time to the metabolic clinic, and gestational week when metabolic control was achieved.

Our study's findings may be used to target educational messages to women with PKU and to direct future research directions. For example, obstetric knowledge of maternal PKU needs further evaluation. Discrepancies should be resolved between maternal PKU medical recommendations and the policies of third party-payers. The disparities in financial assistance and services available to pregnant women with PKU residing in different states should be examined further.