Evening Primrose Oil
Evening Primrose Oil or EPO is a rich source of omega 6 essential fatty acids and gamma-linoleic acid or GLA, which is converted in the body to form prostaglandins - hormone-like substances that can thin the blood, relax blood vessels to lower blood pressure and help maintain water balance. Prostaglandins can also help ripen a pregnant woman's cervix (as can the prostaglandins present in a man's semen). Some caregivers or practitioners suggest the use of Evening Primrose Oil either orally or vaginally during the last few weeks of pregnancy to help ripen the cervix and perhaps reduce the chances of the pregnancy going overdue and maybe to shorten the labour.
To date there have been few studies to show how effective this might be. One study of 108 first-time pregnant women (54 who took EPO orally from 37 weeks and 54 women who did not) showed it did not shorten the pregnancy or decrease the overall length of their labours. What they did find though was that oral EPO may increase in the incidence of the waters breaking early and labour not starting, requiring an oxytocin drip to induce or augment the labour. This makes sense as EPO can soften or weaken the sac containing the water the baby floats in.
Many caregivers do not recommend taking EPO at all during pregnancy, as it can cause bleeding and premature labour contractions. If EPO is taken, then it should only be during late pregnancy and then only 1000mg or less per day. At this stage we would NOT recommend that women put EPO capsules directly into their vagina during pregnancy.
Herbs
Herbs have been used by women for centuries to help start labour. In recent years
raspberry leaf tea and tablets have been widely used by women during the last few weeks of their pregnancy. The aim being to increase uterine muscle tone, reduce the chances of going overdue and preparing them for more efficient or faster labour. However, recent research has failed to support all these claims.