Fern test, getting pregnant

Fern test: a test used to determine ovulation, but also to determine whether there is loss of amniotic fluid. The fern test is most often used as an ovulation test. This test was extremely popular at the beginning of the 21st century, but then this method declined somewhat. However, it is still a test that provides a reliable picture when used correctly. A good test to become pregnant, but also to prevent pregnancy. Saliva or vaginal fluid can be used for the fern test.

What is the fern test?

The fern test is a method to indicate ovulation or ovulation. This is used by women who want to become pregnant. In addition, a fern test is used to demonstrate whether the membranes have broken or loss of amniotic fluid. More about this method later. The fern test is mainly known to women who want to become pregnant and recognize their fertile period. The test can be used to determine ovulation. This is useful to know, because around this period you can have sex. This increases the chance of pregnancy.


The Donna test, Donna test or Donna tester is an ovulation test to determine the fertile period. This tester is often used by women who want to become pregnant, but also by women who do not want to become pregnant and use it as a contraceptive. The Donna test is a home test that shows the fern structure of saliva or vaginal fluid.

Fern structure and fertility

A few days before ovulation, more estrogen is released into the body. This peaks around ovulation and decreases about 2 to 3 days after ovulation. An increased estrogen level affects the structure of vaginal fluid, but also that of saliva. When the moisture has dried, a fern structure can be observed during the fertile period. Outside the fertile period, the moisture dries into spots. With a home test, some vaginal fluid or saliva can be smeared on a glass slide every day. This must then dry, which takes about 15 minutes. The structure of the dried moisture can then be examined through a viewer with a magnifying glass. When a fern structure is visible, this is a sign that the fertile period has begun.


Various stories are circulating about the reliability of the tester. The manufacturer itself says that this test is up to 98 percent reliable. Users themselves have varying degrees of enthusiasm about it. Some people have good experiences with it, while others cannot handle it or do not achieve good results. It is important that the tester is used correctly. Many women do not have the patience to allow the moisture to dry sufficiently or do not remove air bubbles. This affects the result. There also appears to be a difference in the type of moisture used for the test. In general, vaginal fluid gives slightly better results than saliva. The difference between the two is 1 to 3 percent. In general, the fern test is a method that is also used by doctors, although it requires somewhat better equipment than the home test. Nevertheless, the fern test can be a good and reasonably reliable method to determine ovulation.
It is best to use the test for 1 to 3 months in addition to another method to determine ovulation, such as the temperature method or with ovulation tests using urine sticks. It is often clearer what one sees in the picture in terms of structure: fern or dots. Because the test is also used as a contraceptive, it is important to first use the test for a number of months and become familiar with it. In the meantime, another method of contraception should be used to prevent pregnancy. Because the test is not 100 percent reliable and because a (cheap) home test in particular shows abnormalities more often, a higher chance of an (unwanted) pregnancy must be taken into account.

Broken membranes and the fern test

Sometimes it is unclear whether the waters have broken and the woman is losing amniotic fluid or whether this is due to urine loss or increased secretion. There are a number of methods to determine this. An ultrasound can be used to see how much amniotic fluid is still in the uterus. In addition, a fern test can be done to determine whether the fluid is really amniotic fluid. The woman collects some fluid in a jar or via a plastic bandage that is placed in her underwear. As with the other test, the moisture is placed on a glass slide and allowed to dry. The structure of the dried moisture can then be viewed through the microscope. If a fern structure is visible, this is certainly amniotic fluid. However, it sometimes happens that no fern structure was visible, but it was amniotic fluid. Not every test is 100 percent reliable.

read more

  • Getting pregnant: temperature method
  • Getting pregnant and fertile mucus
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