Eating "lotus seeds" during pregnancy will cause any side effects?

Possibly but ??: Lotus Seeds are used as a food and herb in Asian countries and particularly in China, where it's used in traditional Chineese Medicine to prevent miscarriage in pregnancy in women with a history of prior miscarriage. I could find no definite citation that it's unsafe in pregnancy, but there have been no studies as to safety in pregnancy or efficacy in preventing miscarriage.