Patient awareness about family planning represents a major knowledge gap in multiple sclerosis.

Background: The purpose of the survey was to assess the knowledge of family planning issues associated with disease modifying therapies (DMTs) among patients diagnosed with multiple sclerosis (MS).

Methods: 590 Danish MS patients responded to an online questionnaire about family planning in MS, collecting demographics, disease characteristics, disease modifying treatment, knowledge of potential teratogenic effects in DMTs, number of children, occurrence of unplanned pregnancies and outcome, and sources of information.

Results: 488 females and 102 males, mean age 40 years, responded. On average, it was 6.5 and 10.9 years since diagnosis and first symptoms, respectively. 16% of female and 19% of male respondents did not receive DMT at the time of responding to the survey. 30% of all had received only one DMT, 37%, 19%, 8%, and 5% had received two, three, four, and five different treatments, respectively. 42% of female and 74% of male respondents said they did not know if the medication they were taking had teratogenic risks. 83% of females and 85% of males responded that they did not know, whether DMT in male MS patients may expose healthy partners to teratogenic risks; hereto, 13% and 10%, respectively, answered that no transmission occurs. On average respondents had two children; three of four children reported in the study were born prior to the respondents being diagnosed with MS. 50% of both female and male respondents without children wanted a family and 25% of females and 16% of males wanted to start a family within the next two years. 91% of female respondents would discontinue DMT during pregnancy. Among male respondents 32% would continue treatment during a partner's pregnancy and 47% did not know whether they would continue or discontinue treatment. 10% of the female patients had had unplanned pregnancies during MS treatment, of these 49% chose to have an abortion. 53% of all felt they were well informed about MS treatment and family planning. 22% and 41% of the respondents received information from the neurologist about teratogenic risks in female MS patients and about teratogenic risks in women with male MS patients as partners, respectively; 27% and 34%% retrieved information from the internet on these two issues.

Conclusion: This survey uncovered a low level of knowledge about DMTs' teratogenic risks among MS patients irrespective of sex. Knowledge about potential teratogenic risks for male MS patients receiving DMTs while planning to start a family was largely absent. 10% of female patients had experienced unplanned pregnancies on MS treatment. In general, patients use the internet and their neurologist to the same extent for information on parenthood planning.