This information was found and complied at (http://www.waterbirthinfo.com/benefits.html)
Greater comfort and mobility. The mother has much greater ease and freedom to move spontaneously and to change position to assist the descent of the baby.
Reduction of pressure on the abdomen. Buoyancy promotes more efficient uterine contractions and better blood circulation, resulting in better oxygenation of the uterine muscles, less pain for the mother, and more oxygen for the baby.
Helps mother to conserve her energy. Immersion reduces opposition to gravity; supports the mother's weight so that her energy can be used to cope with the contractions.
Promotes deeper relaxation. As a woman relaxes deeply in water, her hormones kick in and she starts progressing faster and with more rhythm; labor becomes more efficient.
Water relaxes the pelvic floor muscles.
Water minimizes pain so effectively that for most women other pain control methods are no longer needed.
Water stimulates the touch and temperature nerve fibers in the skin. It blocks impulses from the pain fibers, known as the Gate Theory of Pain.
Immersion is often more effective and safer than an epidural. Some people call waterbirth an "aquadural."
Facilitates a dysfunctional labor. Water can be an effective way to stimulate dilation of the cervix when the mother has difficulty progressing into the active stage of labor.
Water can reduce the need for drugs to artificially stimulate labor. Often, simply getting into the tub will result in dramatic and rapid progress to full dilation within an hour or two.
Lowering of blood pressure. When anxiety is causing high blood pressure, immersion in water often helps lower it.
Change of consciousness. Immersion helps relieve anxiety and promotes relaxation. Water helps a woman to let go and focus inward as labor strengthens.
Easier breathing. Moisture in the air makes it easier to breathe and can be helpful to women with asthma.
Facilitates the second stage of labor. Many mothers are less inhibited in the water. The warm water softens the vagina, vulva, and perineum, leading to fewer injuries to these tissues.
Many women experience rapid second stages, with the baby emerging minutes after the body starts pushing, also known as the fetus ejection reflex (see Odent, The Nature of Birth and Breastfeeding).
Empowerment of the mother. When a woman delivers her baby while remaining awake, aware and in control, it greatly enhances the birth experience for her and becomes a source of great personal strength and power that enriches her life forever.
Greater involvement of the father. Because the mother's pain and stress is so greatly reduced, it is much easier for fathers to particpate and take a more active role in the birthing process. Many men are reluctant to become involved in the birth experience when they know that the mother is likely to endure intense pain, trauma and suffering during labor and delivery.
Enhanced family relationships. When the mother's pain is dramatically reduced, many fathers eagerly take a more active role in the delivery, resulting in a greater family bond. When fathers are more involved it increases the possibility of a joyous birth. Both parents and child get to share a wonderous experience that can enhance their relationships with each other for the rest of their lives.
Better parent-child interactions. A mother who has had a beautiful and empowering birth experience will have an especially positive association in her mind and emotions to that child; and a baby who has had an easy, non-traumatic, not painful, gentle birth will have an especially positive association to the parent. This exceptionally positive start to their relationship will likely enhance the parent-child interactions forever.
Evolving humanity in a positive direction. Many psychologists believe that babies born gently grow up to become more gentle adults, and have a greater ability to deal with problems non-violently.
Resources: Daniels, 1986; Balaskas, 1990; Lichy, 1993; Napierala, 1994.
Thanks to Andrea Eastman of the Gentle Birth Alternatives Home Page for her help in compiling this section.