PREFERENCES OF PREGNANT WOMEN AND FAMILY MEMBERS FOR COMBINED MATERNAL-FETAL HEALTH STATES ARISING FROM THE USE OF ANTICOAGULATION IN PREGNANCY

   Purpose: To elicit preferences of pregnant women and their family member(s) involved in decision-making for combined maternal and fetal health-states arising from the use of anticoagulation in pregnancy thereby addressing competing interests of mother and fetus.

 

   Methods: We conducted a cross-sectional study on pregnant women taking medications for medical disorders and their family member(s) involved in decision-making. Study participants completed a questionnaire eliciting demographic information and risk-taking attitudes. Pregnant women and their family members - interviewed separately and together - were presented with seven vignettes representing combined maternal and fetal health-states  (perfect maternal health, maternal blood clot, perfect fetal health, major or minor congenital malformations and fetal demise, in various combinations) related to anticoagulation use in pregnancy. They were asked to rank these health-states and assign values using visual analogue scale (VAS), standard gamble (SG) and time trade-off (TTO) methods. Data were checked for consistency of rankings with irrefutable ordering. Utility values for single women, pregnant women in relationships, family members and for shared interviews were presented on a scale of 0-100 where zero represented maternal (and fetal) death and 100, perfect maternal and fetal health.

 

   Results: Fifty-six pregnant women (six of whom were single mothers), 43 family members and 40 pairs completed the interviews. The median age was 32.9 years for pregnant women and 37.1 years for family members, and the median gestational age was 28.9 weeks. Most respondents were Canadian, of Caucasian descent, employed with post-secondary education, had an individual annual income of over $40,000, no religious affiliation, had spontaneous planned conceptions with at least one living child and were risk-averse. Utility values obtained are presented in Figure 1. SG values were greater than TTO values and utilities obtained from shared interviews were higher than those of pregnant women and closer to those of family members. 

 

   Conclusions: This is the first study to determine preferences for combined maternal-fetal health-states from pregnant women and family members. It demonstrates feasibility of making trade-offs between maternal and child health across three instruments and provides a framework for eliciting patient-preferences in pregnant women.

 

Figure 1: Utility values for combined maternal-fetal health-states from pregnant women, family members and shared interviews using visual analogue scale (VAS), time trade-off (TTO) and standard gamble (SG) methods.