This is best to purchace as a bundle. To use only during birth when you are full term and are in an established labour.
Combination of oils helps the birth to be efficient, helps the contractions, encourages effective dilation, keeps you relaxed and happy. 
You can and should (if it feels right for you) keep using the oils to birth the placenta.
 
Pure essential oils blend to use in a diffuser
5ml Pure oils mix to use in a diffuser, or mix with carrier oil. You can also use this blend to top up your smelling salt.