A dry birth is an obsolete term that refers to a birth with a low level of amniotic fluid. According to Sutter Health, the term "dry birth" is a misnomer, since one-third of the volume of amniotic fluid is replenished every hour. The medical term for low levels of amniotic fluid is oligohydramnios.
The March of Dimes Foundation states that oligohydramnios during labor increases the risk of umbilical cord compression, infection and the likelihood of a cesarean section being performed. Several risk factors can cause oligohydramnios, such as a pregnancy that is two weeks or more past the due date, maternal high blood pressure, and fetal birth defects involving kidney and urinary abnormalities.
When there is a spontaneous rupture of membranes, amniotic fluid either gushes or leaks out of the vagina. Although most doctors and midwives like to deliver within 24 hours of the rupture of amniotic fluid, some do allow their patients to labor longer, which can cause amniotic levels to drop lower, as explained by Sutter Health.
According to Medscape, amniotic fluid is inhaled by the fetus to help the lungs develop and protects the fetus from trauma and infection. During pregnancy, the fetus swallows amniotic fluid that helps in the development of the digestive system as well as creating urine and meconium.