Oligohydramnios is the condition of having too little amniotic fluid. About 8 per cent of all pregnant women are found to have low amniotic fluid at some point, usually in their third trimester. Among those still pregnant two weeks past their due date, 12 per cent have this condition. Amniotic fluid provides the fetus with fluid and nutrients, protects the fetus from trauma, has antibacterial properties and is necessary for the development of a healthy fetus. Studies have suggested that dramatic changes in amniotic fluid volumes can be a reflection of abnormalities in maternal or fetal status increasing the risk of perinatal morbidity and mortality.
The volume of amniotic fluid is ultimately determined by the volume of fluid flowing into and out of the amniotic sac. Fetal urination, lung fluid, and swallowing all make important contributions to fluid movement in late gestation, with minimal contributions from other sources. Fetal disorders that affect any of these processes.
What causes oligohydramnios?
Birth defects – Problems with the development of the kidneys or urinary tract which could cause little urine production, leading to low levels of amniotic fluid.
Placental problems – If the placenta is not providing enough blood and nutrients to the baby, then the baby may stop recycling fluid.
Leaking or rupture of membranes – This may be a gush of fluid or a slow constant trickle of fluid. This is due to a tear in the membrane. Premature rupture of membranes (PROM) can also result in low amniotic fluid levels.
Post Date Pregnancy – A post date pregnancy (one that goes over 42 weeks) can have low levels of amniotic fluid, which could be a result of declining placental function.
Maternal Complications – Factors such as maternal dehydration, hypertension, preeclampsia, diabetes, and chronic hypoxia can have an effect on amniotic fluid levels.
Medications – Certain drugs may cause oligohydramnios. Some drugs are used for management of high blood pressure, should be avoided in pregnancy as they affect the baby’s kidney function. Certain drugs used to postpone premature labour such as indomethacin or even ibuprofen may also affect the kidney function of the baby. Talk to your doctor if you need to use these medications during your pregnancy.
An unusually large number of diagnoses seem to be made that “there is not enough amniotic fluid.” It is important for parents to know that this is likely an inaccurate assessment. The diagnosis is confirmed by ultrasounds. An ultrasound examination during the second and/or third trimester of a pregnancy is a good tool to help detect the presence of oligohydramnios but it should not dictate to mothers that it is the only way. Ultrasound evaluations of amniotic fluid volumes are becoming a standard part of antepartum assessment of fetal well-being with variances in fluid levels leading to interventions that can increase the risk to both mother and baby. So, here’s the point. If your doctor says, “Your fluid is low, we need to induce,” don’t blink blindly and say, “OK.” The problem is that it is very often hard to determine “oligo” with certainty.
This measurement is commonly taken by using an ultrasound to determine the Amniotic Fluid Index (AFI). The AFI was introduced in 1987 to replace the 2 cm “pocket technique” of fluid assessment, and studies continue to question to what extent the AFI reflects actual amniotic fluid volume. The most recent studies say that the AFI is not a great predictor of the Amniotic fluid volume (actual amount of fluid. Doctors want to know the results of a Biophysical Profile to see what is going on. A biophysical profile is a simple, painless test that’s performed during pregnancy to assess a foetus’s well-being – specifically, whether he’s getting enough oxygen inside the uterus or not.
The following criteria are assessed during a biophysical profile:
- Amniotic fluid index (AFI) – four pockets of fluid are measured; two pockets must measure 2 cm or more for a score of 2
- Fetal breathing – fetuses “practice breathing” by contracting and relaxing the diaphragm muscle; a score of 2 is assigned for fetal breathing lasting 30 seconds or more
- Fetal tone – the full extension and flexion of a limb such as opening and closing a hand
- Gross body movements – two or three episodes of movement such as squirming or kicking.
- Pregnant women should ask questions such as can I get some fluids (IV, etc.) and retest? Here’s some additional good info on AFI here especially relevant to “post-dates” pregnancy.
I have been seeing so many women who say their doctor wants to do a repeat ultrasound or just go ahead and induce on a certain day because it looks like the amniotic fluid is low. These test can be sometimes so innaccurate and midwives should make people aware of this unnecessary intervention. Women should think twice before agreeing to the an induction. They should ask questions and every question posted should be answered by midwives and OB/GYN.
What I have found is most often, a woman will refuse induction on or around her due date. The doctor, for fear of liability, will order her to come in once or twice a week for non-stress tests (NST or CTG), in which they measure her amniotic fluid. These doctors will then tell the pregnant woman her fluid level is low, and they now have a medical reason to induce, and will promptly send her to the hospital. This tactic seems to be a way to convince a woman to do what the doctor tells her to by scaring her with medical jargon.
What treatment options are available for women with oligohydramnios?
A Cochrane systematic review by Hofmeyr and Gulmezoglu concluded that maternal hydration appears to increase amniotic fluid and may be beneficial in management of oligohydramnios. The amount of fluids a woman drinks daily directly influences the amount of fluid in your uterus. A 2009 study in the “Journal of Obstetrics and Gynaecology Research” demonstrated that pregnant women who had low amounts of amniotic fluid were able to increase the amount of amniotic fluid through oral hydration.
Pregnant women should be careful to drink at least 10 cups of fluids daily, according to the Institute of Medicine. The majority of your fluids should be water, although you can also get fluids from decaffeinated tea, soup and fruit juices. Midwives should advise pregnant women to stay hydrated and monitor the baby’s movements.
To improve the Amniotic fluid level Glucose, coconut water, water, fresh juices.etcc should be consumed.
Drinking tender coconut water in morning and evening will increase weight of baby also. Watermelon is also a good item to consumed during summer time when the water level in pregnant women decreases.
Drink 1 glass of water every half an hour and pass urine at least once in a hour. This will help in preventing urinary infection also.
Boyd, R.L. & Carter, B.S. (2002). Polyhydramnios and Oligohydramnios. e Medicine.
Retrieved from http://www.emedicine.com/
Hofmeyr, G. J., Gulmezoglu, A. M. (2002). Maternal hydration for increasing amniotic fluid volume in oligohydramnios and normal amniotic fluid volume. In: The Cochrane Library, Issue 1, Oxford: Updated Software.
Mozurkewich, E., Chilimigras, J., Koepke, E. et al. (2009). Indications for induction of labour: a best-evidence review. BJOG. 116(5):626-36.
Phelan, J. P., Smith, C. V., Broussard, P., Small, M. (1987). Amniotic fluid volume assessment with the four-quadrant technique at 36–42weeks’ gestation. J Reprod Med. 32:540–542.