Just copied and posted this but I hope it helps.
Rosemary essential oil is discouraged for use in pregnancy by most reputable sources. Julia Lawless, in "The Illustrated Encyclopedia of Essential Oils," also advises against the use of rosemary oil in pregnancy. Although research, to some extent, is inconclusive on the safety of the use of rosemary essential oil in pregnancy, pay attention to the contraindications and do not put your baby at unnecessary risk.
Read more:
http://www.livestrong.com/article/204494-rosemary-essential-oil-pregnancy/#ixzz2Gb4JZL43