“A majority of women experience some nausea and/or vomiting during pregnancy. This condition can range from mild nausea to extreme nausea and vomiting, with 1-2% of women suffering from the life-threatening condition hyperemesis gravidarum.

Cannabis (Cannabis sativa) may be used therapeutically to mitigate pregnancy-induced nausea and vomiting.

This paper presents the results of a survey of 84 female users of medicinal cannabis, recruited through two compassion societies in British Columbia, Canada. Of the seventy-nine respondents who had experienced pregnancy, 51 (65%) reported using cannabis during their pregnancies. While 59 (77%) of the respondents who had been pregnant had experienced nausea and/or vomiting of pregnancy, 40 (68%) had used cannabis to treat the condition, and of these respondents, 37 (over 92%) rated cannabis as ‘extremely effective’ or ‘effective.’

Our findings support the need for further investigations into cannabis therapy for severe nausea and vomiting during pregnancy.”

https://www.ncbi.nlm.nih.gov/pubmed/19880090

“Marijuana use is common in pregnancy but may not be an independent risk factor for poor neonatal outcomes in term pregnancies.”  http://www.sciencedirect.com/science/article/pii/S000293781500527X