We have learned that amniotic fluid serves as protector of the fetus inside the womb. And it also serves as aid or lubricant during true labor. If the pregnant mother has just the right amount of amniotic fluid in her womb, delivery of the baby is very easy. The fetus is positioned inside the amniotic sac. During its two weeks of pregnancy, the amniotic fluid starts to develop and gradually the amniotic fluid fills the amniotic sac. The amniotic fluid serves as protector of the fetus. Being a protector it hold a lot of nutrients, some hormones and a lot of antibodies. The amount of amniotic fluid in the amniotic sac is up to one quart or approximately 1and ¼ liters until the pregnancy comes to the end of seven months. By the time the pregnancy reaches to eight and nine months, the amniotic fluid begins to drop in preparation of labor. In most cases, the amniotic fluid, instead of dropping it stays on same amount of amniotic fluid which is one quart. High level of amniotic fluid can also cause problem to the baby.
Polyhydramnios is a medical term used to describe high level of amniotic fluid. Polyhydramnios affect the fetus when it occurs during fourth month of pregnancy. Complications of Oligohydramnios and Polyhydramnios are almost the same. Among complications of Polyhydramnios are the following:
• Premature delivery. Excessive amount of amniotic fluid will induce labor, thus premature delivery happens.
• Placental abruption. Because of high level of amniotic fluid, the placenta is partially and worse it is completely detached from the uterine wall.
• Still birth. When there is high level of amniotic fluid, the amniotic fluid cannot do its function of protecting the fetus; rather it gives out toxins that are dangerous to the fetus.
• Postpartum hemorrhage. High level of amniotic fluid causes excessive bleeding after delivery.
The true cause of Polyhydramnios is until now being studied, though there are possible causes why these kinds of complications happen during pregnancy.
• Mother and child blood incompatibility (RH disease). The baby acquires Rh factor both from mother and father. See example below.

Father Rh factor Mother Rh factor Baby Rh factor
++ ++ ++
++ -- +-
+- +- ++
-- +- +- or --
-- -- --
In Rh factor the only thing that causes a problem is when the mother has a negative Rh factor and the baby got positive Rh factor.
• Polyhydramnios is worsen when a mother has diabetes.
• Fetal infection can also cause polyhydramnios.