Amniotic fluid is an important part of the baby’s life support system. Amniotic fluid is generally produced after 12 days of conception once amniotic sac is formed. Initially Amniotic fluid takes water from mother’s body and after 20 weeks urine of fetus forms the main substance.
It protects baby from any injury and also helps in the development of fetus muscles, limbs, digestive system, and lungs. It allows the fetus to grow, tumble and move in the mother’s womb.
Sometimes amniotic fluid may be produced in very low or high quantity. Measurement of amniotic fluid is too low it is called oligohydramnios. A condition of low amniotic fluid measurement is also called as Oligohydramnios. A high measurement of amniotic fluid is called as polyhydramnios.
Worldwide, out of 8% of pregnant women having low amniotic fluid approximately 4% are being diagnosed with Oligohydramnios. It is most commonly detected in the third trimester and may cause more serious complications in pregnancies longer than 41 weeks. This condition may be a life-threatening situation for fetus due to cord compression, insufficient oxygen or immature lungs development.
Etiology of low Amniotic fluid-
- Birth defects: Low amniotic fluid production can be caused due to problem in the development of fetus urinary tract or kidneys.
- Placental issue: When placenta is not able to provide sufficient blood and nutrients then the fetus may stop recycling of fluid.
- Leakage or membrane rupture: A Premature rupture of membranes (PROM) or tear can cause a slow constant trickle or gush of fluid resulting in low amniotic fluid levels.
- Post-natal Pregnancy: A pregnancy that goes over 42 weeks (Post-natal) can result in low levels of amniotic fluid causing decreased placental functioning.
- Maternal risk factors: Various maternal complications like diabetes, hypertension, preeclampsia, dehydration, and chronic hypoxia can cause low volume of amniotic fluid levels.
The Associated risks of having low amniotic fluid
In the first trimester, it is more risky-
- Birth defects due to compression of fetal organs
- Miscarriage or still-birth
In the second trimester risks are-
- Intrauterine Growth Restriction (IUGR)
- Preterm birth
Diagnosis and Treatment
Amniotic fluid is evaluated using the amniotic fluid index (AFI). Here, fluid packets are measured in four different areas of the uterus and final calculation is done by adding all measurements together to analyze final score on the index. The normal AFI range should be anything between 5 cm and 25 cm which indicates enough amniotic fluid to support fetal health. A value less than 5cm is a cause for concern, and necessary precautions should be taken for the rest period of pregnancy.
The treatment of oligohydramnios is usually given as per gestational period. A preterm condition of a mother is usually monitored very closely. Baby’s activities are monitored with non-stress and contraction stress. In full-term with low amniotic fluid levels, doctors usually recommend delivery of a child.
Various other treatment procedures that can be used are Amnio-infusio, Amniocentesis and maternal re-hydration with oral or IV fluids.