When does pregnancy hormone show up

Pregnancy | FDA

What does this test do? This is a home-use test kit to measure human chorionic gonadotropin (hCG) in your urine. You produce this hormone only when you are pregnant.

What is hCG? hCG is a hormone produced by your placenta when you are pregnant. It appears shortly after the embryo attaches to the wall of the uterus. If you are pregnant, this hormone increases very rapidly. If you have a 28 day menstrual cycle, you can detect hCG in your urine 12-15 days after ovulation.

What type of test is this? This is a qualitative test -- you find out whether or not you have elevated hCG levels indicating that you are pregnant.

Why should you do this test? You should use this test to find out if you are pregnant.

How accurate is this test? The accuracy of this test depends on how well you follow the instructions and interpret the results. If you mishandle or misunderstand the test kit, you may get poor results.

Most pregnancy tests have about the same ability to detect hCG, but their ability to show whether or not you are pregnant depends on how much hCG you are producing. If you test too early in your cycle or too close to the time you became pregnant, your placenta may not have had enough time to produce hCG. This would mean that you are pregnant but you got a negative test result.

Because many women have irregular periods, and women may miscalculate when their period is due, 10 to 20 pregnant women out of every 100 will not detect their pregnancy on the first day of their missed period.

How do you do this test? For most home pregnancy tests, you either hold a test strip in your urine stream or you collect your urine in a cup and dip your test strip into the cup. If you are pregnant, most test strips produce a colored line, but this will depend on the brand you purchased. Read the instructions for the test you bought and follow them carefully. Make sure you know how to get good results. The test usually takes only about 5 minutes.

The different tests for sale vary in their abilities to detect low levels of hCG. For the most reliable results, test 1-2 weeks after you miss your period. There are some tests for sale that are sensitive enough to show you are pregnant before you miss your period.

You can improve your chances for an accurate result by using your first morning urine for the test. If you are pregnant, it will have more hCG in it than later urines. If you think you are pregnant, but your first test was negative, you can take the test again after several days. Since the amount of hCG increases rapidly when you are pregnant, you may get a positive test on later days. Some test kits come with more than one test in them to allow you to repeat the test.

Is this test similar to the one my doctor uses? The home pregnancy test and the test your doctor uses are similar in their abilities to detect hCG, however your doctor is probably more experienced in running the test. If you produce only a small amount of hCG, your doctor may not be able to detect it any better than you could. Your doctor may also use a blood test to see if you are pregnant. Finally, your doctor may have more information about you from your history, physical exam, and other tests that may give a more reliable result.

Does a positive test mean you are pregnant? Usually, yes, but you must be sure to read and interpret the results correctly.

Do negative test results mean that you are not pregnant? No, there are several reasons why you could receive false negative test results. If you tested too early in your cycle, your placenta may not have had time to produce enough hCG for the test to detect. Or, you may not have waited long enough before you took this test.

If you have a negative result, you would be wise to consider this a tentative finding. You should not use medications and should consider avoiding potentially harmful behaviors, such as smoking or drinking alcohol, until you have greater certainty that you are not pregnant.

You will probably recognize incorrect results with the passage of time. You may detect false negatives by the unexpected onset of menses (regular vaginal bleeding associated with “periods”.) Repeat testing and/or other investigations such as ultrasound may provide corrected results.

How early can home pregnancy tests show positive results? | Your Pregnancy Matters

What can we help you find?

Refine your search: Find a Doctor Search Conditions & Treatments Find a Location

Appointment New Patient Appointment
or Call214-645-8300

MedBlog

Your Pregnancy Matters

June 28, 2022

Your Pregnancy Matters

Robyn Horsager-Boehrer, M. D. Obstetrics and Gynecology

Home pregnancy tests can be very accurate if used properly.

Since the earliest recorded history, women have had a strong desire to know whether they are pregnant as early as possible. The body goes through countless changes in the first trimester, and one of the first indicators is a change in the hormones that leave the body through urine.

Ancient Egyptians relied on a form of urine testing to determine pregnancy status way back in 1350 BCE. A woman urinated daily on wheat or barley seeds and if the plants grew, it meant she was pregnant. Modern-day validation suggests that test was about 70% accurate in detecting human chorionic gonadotropin (hCG), a hormone produced by a woman’s body soon after implantation of a fertilized egg inside the uterus.

Thankfully, urine-based pregnancy tests have evolved substantially. Women now have access to advanced tests that can detect a pregnancy as early as eight days after ovulation. But while many home pregnancy tests are marketed as simple and effective, getting accurate results comes down to how early in your ovulation cycle you take the test.

Ovulation generally occurs around day 15 of a 28-day cycle. In a normal pregnancy, an egg is fertilized in the fallopian tube and then travels into the uterus, where it implants in the uterine wall. After implantation, production of hCG starts from cells in the developing placenta (tissue that will feed the fetus). Trace levels of hCG can be detected as early as eight days after ovulation.

That means you could get positive results several days before you expect your period to start. However, the first part of your cycle is more variable than the second, making it tricky to determine the best time for an early test.

“Thankfully, pregnancy tests have evolved substantially since the 20th century. Women now have access to advanced tests that can detect a pregnancy as early as eight days after ovulation.”
– Robyn Horsager-Boehrer, M.D.

When to take a home pregnancy test

The length of time from the first day of a period to ovulation can vary by several days from month to month. Sexual activity around ovulation leads to the possibility of fertilization of an released egg by sperm. But even then, the time frame for a fertilized egg to implant can vary. And hCG isn’t produced until after implantation has occurred.

For the most accurate results, we recommend testing in the morning on the day you expect your period to start. This allows for variability in the timing of ovulation, fertilization, and implantation. Testing in the morning provides a more concentrated urine sample.

Follow the directions carefully to get the best results. Before you take the test, make sure you understand what the readout for “pregnant” and “not pregnant” will be. Some tests still use two lines to indicate you are pregnant and one to indicate that you aren’t. However, many tests have switched to words such as “yes” and “no”, or “pregnant” and “not pregnant” for additional clarity.

Related reading: Is it OK to use a hot tub during early pregnancy?

Pregnancy test accuracy

Each type of pregnancy test is designed to detect a set minimum level of hCG. This is why pregnancy test manufacturers advertise the way they do: “Know four days sooner,” or “Accurate up to six days before a missed period.” However, while home pregnancy tests are quite accurate – many boast a 99% detection rate based on laboratory testing results – marketing claims can be misleading.

For example, a 99% detection rate means a test can detect hCG 99% of the time on the day you miss your period. These statistics also assume that women are testing at the optimal time and following all instructions correctly.

Many home pregnancy tests available today are midstream urine dip tests, which are the traditional “pee-on-a-stick” tests and are fairly easy to use. There also are tests in which you pee into a cup and dip a test strip into the urine. The New York Times published a story ranking the best home pregnancy tests, citing a midstream test with an ergonomic grip as the easiest to use and most accurate.

Research has shown that average test results when women used the dip tests matched lab test results just 70% of the time, whereas 99% of women typically can get an accurate reading from a midstream test.

False positive and negative results

When a test result is inaccurate, it’s either a false negative (the test says you are not pregnant, but you are) or a false positive (the test says you are pregnant, but you aren’t). Several factors can cause false negative results:

Having too dilute urine after drinking a lot of water or testing later in the day.
Testing too soon when there has not been enough time for a fertilized egg to implant and start hCG production.
Using a pregnancy test that doesn’t detect lower levels of hCG. You can check the package insert for more information about the level at which the test will be positive.

Sometimes an egg will implant briefly but will not be sustained. This is also called a chemical pregnancy – hCG is produced, but the pregnancy doesn’t continue. A test performed several days before an expected period can show a positive result, but the woman still gets her period soon or on time. Rarely, certain tumors can produce hCG, causing a pregnancy test to be positive even when a woman is not pregnant.

Related reading: It's not your fault: Understanding miscarriage

When to see a doctor

Most women who have a positive pregnancy test should wait a week or two before calling the Ob/Gyn office for a pregnancy blood test or ultrasound to confirm the pregnancy. We suggest waiting because the rate of early pregnancy loss is high, and it’s possible that you might have had a chemical pregnancy.

However, women with a history of ectopic pregnancy or current abdominal pain should call the doctor right away to be examined. Ectopic pregnancies implant outside of the uterus and produce hCG, resulting in positive pregnancy tests. However, these pregnancies can cause abdominal bleeding and prompt medical care is necessary. Women who have congenital heart defects or other chronic physical or mental health conditions should also see a doctor right away because treatment plans or medications might need to be altered to protect the woman and the fetus.

Advances in home pregnancy tests give women greater insight into what’s going on in their bodies sooner than ever before. No matter what your childbearing plans might be, it’s essential to get quick, accurate results at home to plan your next steps accordingly.

To visit with an Ob/Gyn, call 214-645-8300 or request an appointment online.

Human chorionic gonadotropin

IMPORTANT!

The information in this section should not be used for self-diagnosis or self-treatment. In case of pain or other exacerbation of the disease, only the attending physician should prescribe diagnostic tests. For diagnosis and proper treatment, you should contact your doctor.

We remind you that independent interpretation of the results is not allowed, the information below is for reference only.

Human chorionic gonadotropin (hCG, β-hCG, beta-hCG, Human Chorionic Gonadotropin): indications for prescription, rules for preparing for the test, interpretation of the results and normal indicators.

Chorionic gonadotropin is a hormone produced by the outer membrane of the embryo, and is normally determined in the blood and urine of a woman only when pregnancy occurs.

Chorionic gonadotropin consists of two subunits - alpha and beta. The beta subunit (β-hCG) used for the immunometric determination of the hormone is unique. To monitor the course of pregnancy, the determination of the beta subunit of hCG is used. The level of beta-hCG in the blood as early as 6-8 days after conception makes it possible to diagnose pregnancy (the concentration of β-hCG in the urine reaches the diagnostic level 1-2 days later than in the blood serum).

HCG has a multifaceted effect on the body of a pregnant woman: it affects the development of the embryo and fetus, stimulates the synthesis of estrogens and androgens by ovarian cells, promotes the functional activity of the chorion and placenta, and ensures the successful course of pregnancy.

The introduction of hCG into the body of non-pregnant women stimulates ovulation and the synthesis of sex hormones necessary for conception. In men, this hormone enhances the formation of seminal fluid, activates the production of gonadosteroids.

In early pregnancy and up to the 2nd trimester, β-hCG supports the production of hormones necessary to maintain pregnancy, and in male fetuses it stimulates cells responsible for the formation and development of the male reproductive system.

Indications for determining the level of hCG in women:

Absence of menses (amenorrhea).
Exclusion/confirmation of pregnancy, including ectopic (ectopic).
Diagnosis of the condition of the fetus at different stages of pregnancy.
Assessment of the state of the placenta at different stages of pregnancy.
Dynamic monitoring of fetal development during pregnancy, including in the diagnosis of malformations.
Suspicion of the presence of tumor diseases of the reproductive system, such as hydatidiform mole (a rare pathology of the fetal egg, in which instead of developing the embryo, chorionic villi grow), chorionepithelioma (a malignant tumor that develops from the epithelium of the villi of the fetal egg).
Performing artificial termination of pregnancy.

Indications for determining the level of hCG in men:

The presence of suspicion of tumors of the testicles.

Deadline for this study is 1 working day, excluding the day of taking the biomaterial.

The rules for preparing for a blood test to determine the level of hCG are non-specific: it is enough to refrain from smoking and drinking alcohol on the eve of the procedure, limit stress and intense physical activity during the week; blood donation is carried out on an empty stomach.

Determination of hCG in the blood is possible already on the 6-8th day after conception. The use of urinary test systems (rapid pregnancy tests) will be informative starting from the 7th day after the fertilization of the egg. To confirm the result, it is recommended to re-determine the level of the hormone a few days after the first analysis.

Causes leading to high β-hCG levels

Multiple pregnancy.

Incorrect timing of pregnancy.

Pathological pregnancy: the appearance of edema, increased blood pressure, loss of protein in the urine (preeclampsia), convulsions (eclampsia), toxicosis.
The presence of a pregnant woman with chronic diseases (for example, diabetes mellitus).
Multiple fetal malformations (in such a situation, the determination of the level of β-hCG is used together with other indicators, the so-called "triple test". This study is used as a screening, and not for diagnosis.).

Reasons for fixing a decrease in the level of β-hCG

Incorrect timing of pregnancy.
Ectopic pregnancy.
Frozen pregnancy.
Threat of miscarriage.
Fetal or placental disorders (including placental insufficiency).
Intrauterine fetal death (in this case, it is informative to determine the level of the hormone in the first and second trimesters).

During abortions, the level of β-hCG is also monitored, the dynamics of growth / fall of which can be used to judge the completeness of the manipulation.

Determining the level of hCG, in addition to establishing the fact of pregnancy in the early stages, is part of the screening examination of pregnant women in the first trimester, along with ultrasound. {{ANALYSIS_LIST|PRS1}}{{DIAGNISTIC_LIST|718}}
In gynecological practice, human chorionic gonadotropin is used to treat infertility, stimulate ovulation, and synthesize sex steroids. In urology, it is used in the treatment of cryptorchidism (undescended testicles) and infertility associated with impaired spermatogenesis.

Quantitatively, β-hCG is determined in the blood, for a qualitative determination, special test systems (pregnancy tests) are used, and in this case, urine serves as a biomaterial.

Quantitative determination of the level of hCG allows you to monitor the course of pregnancy in dynamics. To do this, obstetrician-gynecologists have developed tables for increasing the level of hCG, depending on the duration of pregnancy in weeks. The sensitivity of the determination is in the range of 1. 2-1125000 mU/ml. 6–11 20000–>225000 12 19000–135000 13 18000–110000 14 14000–80000 15 12000 –68000 16 10000–58000 17–18 8000–57000 19 7000–49000 20–28 1600–49000 men and non -acquired women 0– <5 Med/ml

Values ranging from 5 to 25 mU / ml do not allow unambiguous confirmation or denial of pregnancy, therefore, a second study is required after two days.

Since the hormone is produced by the placenta, during normal pregnancy, with placental pathology (for example, with fetoplacental insufficiency - a violation of the development of the fetus and placenta), with multiple pregnancies, the values of β-hCG will differ. With a normal pregnancy until the fifth week, the level of the hormone rises exponentially: every two days its concentration doubles, reaching a peak by the 11th week of gestation. Accordingly, in a multiple pregnancy, the level of β-hCG will be even higher than in a single pregnancy.

If the indicator deviates from the norm, additional ultrasound of the pelvic organs (uterus, appendages) is required.

However, if the hCG value is normal, additional tests may also be needed:

Ultrasound diagnosis of pregnancy (required to confirm pregnancy, specify the term).
Screening ultrasound of the 1st trimester of pregnancy (11-13 weeks 6 days) - to assess the characteristics and confirm the normal development of the fetus.
Screening ultrasound of the 1st trimester of multiple pregnancy (11-13 weeks 6 days) - to confirm the presence of several fetuses, determine their characteristics; It is necessary for planning the subsequent actions of the doctor and the management of pregnancy.
Ultrasound of the fetus according to indications (up to the 20th week) - is performed if an ectopic pregnancy is suspected.
Lab tests to be performed in the first trimester are collected in the Pregnancy: 1st trimester (1-13 weeks) profile.

For professional assistance in interpreting the results, contact

obstetrician-gynecologist

Sources:

www.invitro.ru .
Ectopic (ectopic) pregnancy. Clinical guidelines (treatment protocol). Moscow, 2017. 36s.
Russian Society of Obstetricians and Gynecologists. Clinical guidelines. premature birth. Moscow, 2016.

IMPORTANT!

Hormones during pregnancy: how does the female body change?

Nausea, chest pain, cravings for pickled cucumbers are all hormones. During pregnancy, you are under their strong influence.

How do they work? Until you became pregnant, most of the hormones in your body were produced by endocrine glands such as the thyroid gland. Now, many of them also form in the placenta, which is inside the uterus. Immediately after the birth of the baby, the placenta is excreted from the body and pregnancy hormones are no longer needed.

Hormones cause nausea during pregnancy.

The culprit is human chorionic gonadotropin , which is produced by the embryo and then by the placenta. It is the presence of this hormone in the urine that leads to a positive pregnancy test result. In addition, human chorionic gonadotropin increases the production of another hormone, progesterone and stops the cycle of menstruation.

Feeling of happiness.

Endorphins These hormones are your biggest allies. These are natural painkillers and calming hormones. They work like morphine. They are called happiness hormones because they are the reason you expect a baby with joy, regardless of nausea and other pregnancy ailments. The source of endorphins is in the brain, where they are produced until the end of labor. The highest concentration of endorphins at the time of childbirth. Thanks to them, the pain becomes weaker, and the stress associated with childbirth is not so tiring. After childbirth, the level of endorphins drops sharply. This is probably the cause of a mild form of postpartum depression.

Sexual attraction.

The estrogens that affect your sex drive are first produced by the ovaries and then by the placenta. Estrogen production rises rapidly at the beginning of pregnancy. Thanks to estrogen, you feel that the desire for intimacy in the first trimester of pregnancy increases. Estrogens increase the blood supply to the breasts, vagina, vulva, and clitoris, which become especially sensitive. It is interesting! Thanks to pregnancy hormones, sex in the second trimester of pregnancy can be the best in a lifetime, according to scientists!

They relax muscles and prevent spasms. This is the influence of one of the most important pregnancy hormones: progesterone . Before pregnancy, it was produced, like estrogens, by the ovaries, now this function has passed to the placenta. Progesterone is responsible for most of the changes in your body during pregnancy (including fever, increased breathing). It relaxes the smooth muscles of the uterus and protects against miscarriage.

Pregnancy hormones prepare you for childbirth.

Preparing for childbirth is the merit of relaxin . Under its influence, the joints of the pelvic bones relax, soften the cervix and increase the elasticity of the surrounding ligaments, so that your uterus will grow, and your child will be able to pass through the birth canal.

Labor spasms.

Prostaglandins and oxytocin are the hormones that most support the final stages of pregnancy. The rising level of oxytocin is responsible for the development of the maternal instinct. In the last trimester, you begin to feel uterine contractions stimulated by prostaglandins. If you have sex, you can speed up labor because prostaglandins are also found in male semen. Oxytocin stimulates predictive uterine contractions or Braxton-Hicks contractions and then the corresponding labor contractions. In some situations, it stimulates labor and accelerates the passage of the placenta.

Help in the first days after childbirth.

Two more hormones, prolactin and placental lactogen , will allow breastfeeding. Thanks to them, the breasts begin to secrete colostrum (the first very nutritious food that can be excreted as early as the 19th week of pregnancy). Your body will produce it within days of giving birth. Later, milk will appear due to these hormones.