Objective To identify factors associated with prolonged Hyperemesis Gravidarum (HG). Study Design About 395 women completed a survey regarding pre-existing conditions, treatments and outcomes. Responses were compared using two-sided t-test or the F-test. Results Participants with prolongs HG are slightly younger and weight more. Pre-existing factors associated with prolonged HG include allergies and a restrictive diet. Prolonged HG is associated with hematemesis, dizziness, fainting and antiemetic treatment. Following pregnancy, those with prolonged HG reported more posttraumatic stress, motion sickness, muscle weakness and infants with irritability, severe colic and growth restriction. Conclusion Multiple pre-existing conditions and poor maternal and infant outcomes were associated with prolonged HG. The most significant condition prior to pregnancy was allergies suggesting a possible autoimmune component affecting duration of HG. In addition, the most significant lifestyle choice linked to prolonged HG was a restrictive diet. Future research is needed to determine whether a change in diet prior to pregnancy may lead to a shorter duration of HG and its associated outcomes.

Objective To determine whether change in paternity changes recurrence risk of hyperemesis gravidarum (HG). Study Design Survey data on recurrence of HG was compared between cases who had a paternity change between pregnancies and cases who did not. Results The percentage of HG pregnancies in women with the same partner for all pregnancies was not significantly different from the percentage of HG pregnancies in women who changed partners for at least one pregnancy (78% vs 71%, p > 0.05). Participants who did and did not change partners between their first and second pregnancies, were asked to rate their first and second pregnancy in regards to symptoms of HG. Neither the ratings nor the change in rating between pregnancies was significantly different between the two groups. Conclusion Women reported HG in over 70% of their pregnancies regardless of paternity change. Paternal genes expressed through the fetus do not have a significant effect on incidence or recurrence of HG. This study supports a strong maternal genetic factor involved in HG. However, because the recurrence risk is not 100%, other factors play a role. Identification of the predisposing gene(s) and other factors will determine the cause of this poorly understood complication of pregnancy.