The fetus is surrounded by and cushioned in a clear, yellowish fluid in the womb known as amniotic fluid. Some women may experience leaking amniotic fluid during pregnancy, too much of which may be harmful.
The amniotic fluid comprises hormones, immune cells, nutrients, and urine produced by the fetus. The fetus starts swallowing and excreting this protective fluid at around 20 weeks. The amniotic fluid helps fetal movement and growth. Also, it prevents infections and injuries to the fetus, supports organ development (e.g., kidneys, intestines, and lungs), and protects the umbilical cord from compressing.
Keep reading this post to learn more about amniotic fluid leakage, how to differentiate it from the leakage of other fluids such as urine or vaginal discharge, and what to do in such cases.
What Is Leaking Of Amniotic Fluid Or Premature Rupture Of Membranes (PROM)?
The premature rupture of the amniotic sac membrane or water bag before the start of labor is called premature rupture of membranes (PROM). If it occurs before 37 weeks, it is called preterm premature rupture of membranes (PPROM). Premature rupture of membranes is rare, and no definite cause is identified despite various etiologies (1).
Normal Levels Of Amniotic Fluid
The normal levels of amniotic fluid vary according to gestational age. The amniotic fluid is visible after 12 days of conception, reaching the highest volume at the 36th week of gestation and declining near birth. Your doctor will measure the amount of amniotic fluid through ultrasound during your prenatal visits. An average amniotic fluid index is between 5cm and 25cm (2).
Amniotic fluid levels during your pregnancy can be (3):
- 60ml at 12 weeks
- 175ml at 16 weeks
- Around 400-1200ml between 34 and 38 weeks
The fluid level declines by around 125ml a week at 38 weeks of gestation and decreases to around 800ml by the 40th week.
Leakage could result in too little of the amniotic fluid in the sac, which could be problematic. Hence, you should detect a possible amniotic fluid leak and seek medical help.
Signs And Symptoms Of Amniotic Fluid Leak
Amniotic fluid come out in a gush when the membrane ruptures. This is also known as a water break, and it usually happens when you enter labor. A small hole in the amniotic sac, it may lead to a slow fluid leak, which feels like the trickle of fluid down to the vagina. Women may find it difficult to determine between amniotic fluid, urine, and vaginal discharge.
The following signs may help you identify amniotic fluid (4):
- Clear or colorless
- Present with mucus or blood
- No odor
- Does not stop leaking
- Soaks pad or underwear often
It may not be amniotic fluid if there is:
- Light- or pale-yellow color
- Thick mucus or look milky
Urine and vaginal discharge have a peculiar odor and color. You may use a pad or panty liner to check these aspects. Another way to know is by holding your pelvic floor muscles for a few seconds. If it is urine, the leakage will stop. If it doesn’t stop, it is probably an amniotic fluid leak. These home tests to confirm amniotic fluid may not be helpful for all women. It is advised to get medical help if you are not sure it is not amniotic fluid.
Causes Of Premature Rupture Of Membranes
A premature amniotic fluid leak may occur from membrane weakening and uterine contractions. The possible risk factors of PROM include (1):
- Recreational drug use
- Alcohol use
- Uterine infection
- Accidental trauma
- Polyhydramnios or too much amniotic fluid in the sac
- Oligohydramnios or too little amniotic fluid in the sac
- Overstretching of amniotic sac and uterus
- Improper prenatal care
- Cervical surgery or short cervical length
- Previous preterm birth
- Sexually transmitted infections
- Less than six months after the previous labor
- Twin or multiple pregnancies
- Second and third trimester vaginal bleeding
- Nutritional deficiencies and underweight
- Connective tissue disorders
The amniotic sac ruptures or water breaks during or at the beginning of labor after 37 weeks of pregnancy. However, the leakage of amniotic fluids before 37 weeks is associated with certain risks.
What Happens When Amniotic Fluid Leaks?
Many women enter labor around 24 hours after the rupture of the membrane or leakage of amniotic fluid at term. If it doesn’t begin in 24 hours, labor is induced to prevent any complications (5). If the fluid leaks before term, it could lead to the following risks (6):
- Infections (both mother and baby)
- Placenta separating from the uterus
- Umbilical cord problems
- C-section delivery
An amniotic fluid leak in the first and second trimester may be associated with an increased risk for congenital disabilities, miscarriage, stillbirth, or preterm labor, whereas in the third trimester, it may cause difficulties in delivery.
When To Call The Doctor?
You should also call the doctor if (7):
- Fluid is green-tinged or brownish-yellow or has a foul smell
- You have vaginal bleeding
- You have a fever or flu-like symptoms such as feeling hot and shivery
- Heart rate has increased
- There is abdominal pain or contractions
- You are uncertain and concerned
The doctor will diagnose your condition based on your gestation age and will also give you an internal examination before the treatment. An amniotic fluid leak is diagnosed by a speculum examination, followed by a pH test and microscopic fluid examination.
While waiting for the doctor, try to stay calm and do not insert anything, such as a tampon or cloth, into the vagina to stop the leakage. Just notice how much fluid has leaked and what the color of the fluid is to let the doctor know.
How Is Amniotic Fluid Leakage Or PROM Treated?
The treatment plan differs for a woman based on the gestational age, cause of fluid leakage, and maternal and fetal health status. If it occurs at term, it is managed with delivery unless there is an indication to wait for spontaneous labor.
If fluid leaks or PROM occurs before term, the next steps could be (8):
- Administers corticosteroids to speed up the maturity of the fetal lung between 24 and 34 weeks of gestation
- Prescribes antibiotics to prevent infection
- Tocolytic medicines to prevent preterm labor
- Delivery to manage PROM unless there are benefits from delaying it without any risks.
- Magnesium sulfate to protect the fetus from neurological complications such as cerebral palsy if delivery is expected within 24 hours before 32 weeks of gestation (9).
- Admission to a hospital for observation and transfer to a hospital where there are good neonatal intensive care facilities just in case the baby arrives early.
If the PROM causes low amniotic fluid levels (10):
- Amnio-fusion: This may be carried out using an intrauterine catheter during labor induction. Adding fluid to make up for the loss of amniotic fluid will provide extra support around the umbilical cord and reduce the chances of a cesarean.
- Re-hydration: You may be given fluids orally or intravenously to increase the amniotic fluid level.
Can You Prevent Premature Rupture Of Membranes?
PROM is generally not preventable but avoiding the risk factors such as smoking, alcohol, and unprotected sex might reduce the probability of the condition (11).
According to one clinical trial study, intake of vitamin C supplements by pregnant women, with a history of PROM, after the 14th week of pregnancy may help reduce the risk of PROM in the current pregnancy (12). However, consult your doctor about the safety and efficacy of its consumption.
Does Leaking Amniotic Fluid Mean Miscarriage?
Leaking amniotic fluid is not one of the common reasons for a miscarriage. However, if it occurs in the second trimester and is accompanied by other symptoms such as abdominal pain, it could be a sign of miscarriage. Nevertheless, you should get it checked by the doctor before concluding anything.
Can Amniotic Fluid Replenish Itself?
The fetus will continue to produce amniotic fluid even if there is a leak, but it may not be enough if there is a heavy leak (13). In a few cases, the amniotic sac may reseal itself and prevent fluid leakage. However, more studies are required to understand the resealing of the sac and replenishing of amniotic fluid after a leak.
Frequently Asked Questions
1. Why do I experience more discharge in general during pregnancy?
It is normal to experience more vaginal discharge during pregnancy due to the softening of the cervical and vaginal walls and the increased progesterone levels. The softening causes an increase in the discharge to prevent any infectious agent from entering the uterus through the vagina (14).
2. Can I leak amniotic fluid and not have contractions?
Yes, you may leak amniotic fluid and not have contractions with it. This may indicate a premature delivery or discharge that is not amniotic fluid (15). As mentioned above in the signs and symptoms, you may differentiate between an amniotic fluid discharge and other discharge based on its color, texture, and flow.
3. Can amniotic fluid leak if my cervix is closed?
Yes, the fetal membrane may rupture even when the cervix is closed and cause amniotic fluid leakage. Although its exact cause may not be known, it is believed to occur from the breakage of the weakest membrane point from an infection, trauma, or internal pressure (16).
The amniotic fluid may gush out as membranes break before delivery. Leaking amniotic fluid before term may occur due to an infection, trauma, nutritional deficiencies, or overstretching of the amniotic sac. The condition may increase the risk of congenital disabilities in early pregnancy. Later it may make the body susceptible to infections and umbilical cord issues and necessitate a C-section delivery. Seek immediate medical help if you suspect leakage of amniotic fluid. Treatment depends on the duration of pregnancy, underlying cause, and health status of the mother and fetus.
Infographic: Difference Between Leaking Amniotic Fluid And Urine Leak
Amniotic fluid leak before the due date requires medical evaluation and necessary interventions since it may lead to preterm birth or other complications. However, it is possible to have urine leaks in the last trimesters of pregnancy due to increased pressure on the bladder. Go through the below infographic to know the difference between an amniotic fluid leak and a urine leak during pregnancy that may help you seek medical care if required.
- Amniotic fluid leakage may occur before labor (PROM) or the 37th week (PPROM).
- Leaking amniotic fluid is distinguishable from other vaginal discharges as the former is colorless, odorless, and might accompany blood.
- The treatment is based on its onset and severity. It can include medications such as corticosteroids, tocolytic medicines, or amnio-fusion.
- Checking with the doctor without delay can prevent complications such as infections or umbilical cord problems.
- Shailja Dayal and Peter L. Hong; (2021); Premature Rupture Of Membranes.
- Megan Lord et al.; (2022); Amniotic Fluid Index.
- Amniotic Fluid: Physiology and Assessment.
- Premature rupture of membranes.
- Overview of Labor.
- Preterm Premature Rupture of Membranes (PPROM).
- Rupture of the Membranes.
- Preterm Premature Rupture of Membranes: Diagnosis and Management.
- Magnesium Sulphate to Prevent Cerebral Palsy following Preterm Birth.
- Low Amniotic Fluid Levels: Oligohydramnios.
- Premature Rupture of Membranes (PROM)/Preterm Premature Rupture of Membranes (PPROM).
- Nayereh Ghomian et al.; (2013); The Role of Vitamin C in Prevention of Preterm Premature Rupture of Membranes.
- R. Devlieger et al.; (2007); Fetal membrane healing after spontaneous and iatrogenic membrane rupture: A review of current evidence.
- Vaginal discharge during pregnancy.
- How to know if your water breaks.
- Antenatal Care Module: 17. Premature Rupture of Membranes (PROM).
- Shehla Noor et al.; Prevalence Of PPROM And Its Outcome.
- A. F. Ray et al.; (2015); Vision Amniotic Leak Detector (ALD) to Eliminate Amniotic Fluid Leakage as a Cause of Vaginal Wetness in Pregnancy: A NICE Medical Technology Guidance.
- Amniotic Fluid.
- Premature Rupture of Membranes at Term.
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Dr. Sangeeta Agrawal(FRCOG, MD, DNB, DGO)
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