You missed your period? You have morning nausea and/or vomiting? You smell strangely? Do you know that you could be pregnant! It is the right time to take your pregnancy test.
How positive pregnancy test works?
Market is full of different types of pregnancy tests but all pregnancy tests are based on one pregnancy element called Human Chorionic Gonadotropin (hCG) – so called “pregnancy hormone”. This hormone is produced by placenta and when Human Chorionic Gonadotropin is present, it usually indicates that the woman is pregnant – actually “positive pregnancy test” means the hCG was detected in woman's blood or urine.
Usually the hCG is made when the fertilized egg implants in the uterus - this usually happens about 6-8 days (average) after the egg and sperm merge. From that moment the amount of hCG rapidly builds up in women body with each passing day of pregnancy.
Sometimes pregnancy tests could have false results – false positive pregnancy test and/or false negative pregnancy test. Even a pregnancy test performed on blood can show a false positive under certain circumstances. In most cases we could have false negative pregnancy test. False positive pregnancy tests are rare, but they do occur.
When is the right time for positive pregnancy test?
Market is full of so called “early pregnancy tests” but how much you can trust them?
Early positive pregnancy test becomes positive ONLY after the fertilized egg has first implanted into the uterus and then sent enough amounts of Human Chorionic Gonadotropin into the blood stream and from there into the urine. This means the positive pregnancy test can be trusted only after implantation (the time when the fertilized egg implants into the endometrium).
In general, the implantation happens about a week after ovulation and it takes another 3-4 days after implantation for the blood pregnancy test to first become positive.
Blood positive pregnancy test appears usually within 3-4 days after implantation or about 9-10 days after fertilization and ovulation.
Urine positive pregnancy test can occur within 2-3 days after the blood test and in most cases until a missed period or about a week after implantation. In most cases only about 25% of pregnant women will have positive pregnancy test 2 days before the missed period and about 40% pregnant women could have positive pregnancy test one day before the missed period.
First Positive Pregnancy Test
Women health is pretty complicated and hormonal menstrual cycle could be also different in each person and ovulation/conception days also could be different. Fertilization and implantation processes also could be different depending on hormones, sperm activities, reproductive organs’ conditions, etc. The amount of time it takes for the fertilized egg to implant in the uterus wall varies widely.
Implantation moment is crucial for pregnancy tests. Usually implantation will occur between 6 - 12 days after ovulation. Once the fertilized egg implants, the developing placenta begins releasing Human Chorionic Gonadotropin (hCG) into the blood. Some hCG also gets passed into the urine. The level of hCG usually double every 2-3 days in early pregnancy. Once the levels are high enough they can be detected by pregnancy tests.
Market is full of pregnancy tests but the sensitivity of all pregnancy tests vary quite widely from brand to brand – usually from 10 mIU to 250 mIU. The lower the level of hCG picked up by the test, the earlier you will see a positive result.
If you use pregnancy test too early or if you use less sensitive pregnancy test, you can get first negative pregnancy test and after few days you could discover positive pregnancy test.
Some blood tests can measure the concentration of the hCG and provide positive pregnancy test as soon as after 6-8 days after ovulation.
Positive Early Pregnancy Test
According to medical standards, the hCG level that’s less than 5mIU/ml is considered negative for pregnancy and levels above 25mIU/ml is considered a positive pregnancy test.
As women are different (especially during fertilization and implantation), all could have positive pregnancy test only at the moment when the hCG level reach 25mIU/ml and more.
Positive Pregnancy Test and missed period
Many women are stressed if they missed their regular period. How soon after missed period you can use pregnancy test? Can pregnancy test be accurate on first day of the missed period?
Some companies claim to be 98-99% accurate on the first day of the missed period. But it is not true in most cases. For avoiding any additional stresses and annoying disappointments most scientists recommend to use pregnancy test after one week of the missed period. It is the time when positive pregnancy test could be trusted in most cases.
CAN POSITIVE PREGNANCY TEST be false?
Very rare positive pregnancy test could be false but it is possible. False pregnancy test always have reasons. In most cases false could be negative pregnancy test.
Positive pregnancy test could be false in following cases:
- If you read pregnancy test late (after the ‘expiry’ period) - then you might get an evaporation line, which can be confused with a positive result;
- If you are using fertility medicine or other hormones for any reason – some drugs can artificially raise the levels of hCG which could be a reason for false positive pregnancy test;
- If you bought expired or bad quality pregnancy test.
POSITIVE PREGNANCY TEST – what to do now?
If your pregnancy test is definitely positive, better to contact your doctor for pregnancy monitoring. To insure healthy pregnancy and healthy baby you would need very special attention.