26 November 2014
Four Major Hormonal Systems Active in Labor and Birth
Oxytocin – Is released by our pituitary gland, deep inside our middle brain during sexual activity, orgasm, labor, birth and breastfeeding.
- Causes the rhythmic uterine contractions of labor.
- The baby also produces increasing amounts of oxytocin in labor and it peaks at birth through stimulation of stretch receptors in a woman’s lower vagina as the baby descends.
- Is produced during breastfeeding causing contractions that protect mother against postpartum hemorrhage.
Beta-endorphins- Is a natural morphine like substance released from the pituitary gland during stress, duress and pain. It has been shown to work on the same receptors of the brain as opiates (Demerol or Morphine)
- Relaxation, massage, movement and positive attitude increase release of endorphins.
- High levels help the laboring woman to transmute pain and find an inner strength to deal with labor pai.
Catecholamine- Are known as the fight or flight hormones (adrenaline and noradrenalin)
- In the first stage labor, high levels can inhibit oxytocin thereby slow labor down as well as high levels can reduce blood flow to the uterus, placenta and baby causing adverse fetal patterns– negative effect.
- In second stage noradrenalin activates the ‘fetal ejection reflex’ which gives mother a rush of energy and strong contractions to help give birth . After birth levels should drop.
Prolactin – Is known as the mothering hormone and is the major hormone of lactation.
- Levels increase during pregnancy, although milk production is inhibited until the placenta is delivered.
- Levels increase during labor and peak at birth. In breastfeeding, prolactin activates the mother’s vigilance to protect her baby and put her baby’s needs first.