Endorphins
The lowdown: When you face stress or pain, your body produces calming and pain-relieving hormones called endorphins. You may have higher levels of endorphins near the end of pregnancy.
The Research:
Endorphins are naturally occurring opiates, similar to morphine and heroin. Like oxytocin, they mostly appear during sex, pregnancy, birth and breastfeeding. Beta-endorphins reduce pain and suppress the immune system, which is important so that it doesn’t act ‘against’ your baby.
For women who don't use pain medication during labor, the level of endorphins continues to rise steadily and steeply through the birth of the baby.
The Pro’s:
High endorphin levels can make you feel alert, attentive and even euphoric (very happy) after birth, as you begin to get to know and care for your baby.
The Con’s:
If you’re stressed during labour, that can make you release excessive beta-endorphins, which may inhibit oxytocin and slow things down. That’s why keeping things as calm as possible is a great thing in labour.
Low levels of endorphins can cause problems in labor and birth by:
Causing labor to be excessively painful and difficult to tolerate.
Leading health care providers to respond to this problem with interventions.
The How:
You can enhance your body's production of endorphins during labor and birth by:
Staying calm, comfortable and confident.
Avoiding disturbances, such as unwelcome people or noise and uncomfortable procedures.
Delaying or avoiding epidural or opioids for pain relief.
http://www.childbirthconnection.org/maternity-care/role-of-hormones/ https://www.nct.org.uk/labour-birth/your-guide-labour/hormones-labour-oxytocin-and-others-how-they-work