A pregnancy test is one of the easiest ways to determine the success of an IVF procedure. Reproductive experts advise taking tests no earlier than two weeks after replanting embryos into the uterine cavity. You should not conduct tests ahead of schedule, as it can give a false positive or false negative result.
Features of the pregnancy test
An increase in hCG levels is a clear sign of pregnancy. To determine its level in the blood, a special test is carried out. Normally, chorionic gonadotropin is produced only after the introduction of the blastocyst into the endometrium. The hormone can be found not only in blood, but also in urine.
Pharmacy express tests allow diagnosing pregnancy with high accuracy (more than 90%). However, they should be carried out no earlier than 2 weeks after embryo replanting. Otherwise, the probability of getting false negative and false positive results will increase several times.
Using test strips
Why shouldn't pregnancy tests be done after embryo transfer ? Pharmacy tests respond to the concentration in the urine of chorionic gonadotropin, which begins to be produced after implantation of the blastocyst into the uterus. If the hormone level is too low, the test strip will give a negative result.
Very often, the results of express tests received before 14 days do not coincide with those that are carried out within the walls of the clinic. There may be several reasons for this:
- a big difference in the content of hCG in urine and blood;
- insufficient sensitivity of the test strip reagent to hormones;
- a change in the level of hormones in the blood associated with the introduction of hCG into the body before the oocyte puncture.
When tested with a test strip, many women get a false negative result. This may be due to insufficient sensitivity of the reagent. For example, already on day 9 after replanting the embryo, the concentration of hCG in the blood can be 21 mU / ml. Most pharmacy tests respond to the hormone only if its level reaches 25 mU / ml.
Negative test result
What if the test is negative after embryo transfer ? If desired, the woman can do a second analysis. But when choosing a suitable test strip, you need to take into account the degree of its sensitivity: the lower the numerical indicator indicated on the package, the higher the susceptibility of the reagent to hCG. Some inkjet and cassette tests have a sensitivity of up to 10 mU / ml. With their help, it is possible to establish the success of IVF as early as 8-9 days after the embryo transfer.
Features of the test
When to do the test after embryo transfer ? As already mentioned, tests should be done 14 days after the IVF procedure. Reproductologists identify several rules that must be taken into account before conducting a test:
- only the first morning urine is used for testing;
- the test results are evaluated after a few minutes;
- the test should be carried out at a temperature of 23-26 degrees;
- the test strip is placed in urine for 5-7 seconds.
Decoding the results
After using cassette, inkjet and other express tests, the following results are obtained:
- negative - most often indicates the absence of pregnancy or fetal freezing;
- dubious - signals the late introduction of blastocysts into the endometrium, ectopic pregnancy or premature express test;
- positive - highly likely indicates successful IVF.
To get a reliable result, it is recommended to have a blood test at a reproductive center. Laboratory techniques are more sensitive, and also allow you to determine the content of hCG in the blood serum. According to the results, one can judge about the features of the course of gestation, the likelihood of multiple or ectopic pregnancy.
Ultrasound after IVF
Only after the ultrasound examination is it possible to judge the success of the IVF procedure. The first ultrasound is performed 21 days after the embryos are transplanted into the uterus. During the hardware examination, the specialist pays special attention to indicators such as:
- localization of the embryo;
- the fact of attachment of the embryo to the endometrium;
- the presence of hypertonicity of the uterus;
- detachment of the embryo;
- condition of the gonads.
With the help of the first ultrasound, not only the pregnancy is confirmed, but also possible pathologies are revealed. If the embryo is fixed in the fallopian tube or inside the ovary, gestation is interrupted. Hypertonicity of the myometrium indicates a high probability of spontaneous abortion. Therefore, if a problem is detected, appropriate treatment is carried out.
Types of ultrasound examinations
To control the features of the course of gestation, 2 types of ultrasound can be used:
- Transabdominal (external) - performed using a sensor that is located on the outer wall of the abdominal cavity. This type of ultrasound is most often used at later stages of gestation - in the 2nd and 3rd trimesters;
- Transvaginal - carried out using a sensitive sensor that is inserted into the vagina. This method is more accurate and allows early diagnosis of pregnancy.
According to statistics, in vitro fertilization is completed successfully in 40% of cases. Often, during the final stage of IVF, several embryos are transferred into the uterine cavity. In most cases, only one of them is implanted into the endometrium, however, the possibility of multiple pregnancy cannot be ruled out. Also, the first ultrasound allows you to identify an ectopic pregnancy, the development of which is fraught not only with the death of the fetus, but also with a rupture of the fallopian tube.
Conclusion
The test for the hCG content allows you to evaluate the effectiveness of the IVF procedure already on the 14th day after embryo replanting. Until this time, it is not recommended to take tests and use express tests, as they can give false negative and false positive results. After 3 weeks, the first ultrasound is done, with the help of which the features of the course of gestation, the likelihood of miscarriage and other pathologies are determined.
