I am going to direct you to THISarticle about how oxytocin helps to reduce stress and promote peace. It's no surprise that oxytocin is the same hormone that is released when we make love, arguably a great stress reliever and a promoter of peace for couples. A lovely consequence of making love when the timing is right: welcome, baby, some 36+ weeks later!
In addition to being the “love” hormome, oxytocin is also produced in great quantity when a woman is in labor. The hard contractions can only happen if the woman’s body is producing ample oxytocin.