The luteinising hormone (LH) surge is the final stage of ovulation. It signals that the egg is ready for fertilisation. If fertilisation does not occur, your period will be triggered. It’s normal for your body to produce high levels of LH during pregnancy; however, some factors can change how much LH you produce and when it peaks. With all the factors at play and the complexity of the menstrual cycle, many people wonder if you can get a false positive pregnancy test during ovulation.
Knowing when your LH peak occurs is critical if you are planning to get pregnant. If you’re unsure whether or not you’re ovulating, taking an ovulation test can help by providing information about when you should have sex to conceive — or when you should do something else to increase your chances of getting pregnant.
Continue reading to learn more about the relationship between a positive ovulation test and pregnancy.
Understanding Ovulation Tests
As mentioned, ovulation tests detect the presence of the luteinising hormone (LH) in urine. The LH surge generally indicates that ovulation will happen within 24 hours.
Ovulation tests are good at detecting the LH surge, but they aren’t perfect. They can be used as part of a broader strategy that includes a fertile window calculator to help maximise your chances of getting pregnant. Using a fertility app like Natural Cycles or Glow, you can collect and harness information to determine when you will most likely be fertile each month.
How Ovulation Tests Work
Ovulation tests detect the presence of the luteinising hormone (LH). Ovulation usually occurs around 24-36 hours after the surge in LH, which is why ovulation tests work best if you take them at least one day before ovulation is expected.
When using a midstream ovulation test, the LH in your urine reacts with a special reagent. The reagent will change colour if enough LH is present, indicating that you’re ovulating.
Will an Ovulation Test Be Positive if I’m Pregnant?
Ovulation tests are primarily used to predict ovulation. The test will not be positive until the LH hormone level has reached the correct threshold, triggering the release of an egg.
On the other hand, pregnancy tests test for the presence of a completely different hormone — human chorionic gonadotropin (hCG). The production of hCG ramps up the following conception.
Given that ovulation tests do not test for hCG, they cannot be used to confirm that you are pregnant. However, the menstrual cycle is quite complex, and some women may coincidentally record a positive ovulation test while pregnant.
The Luteinizing Hormone Surge and Pregnancy
The luteinising hormone (LH) surge marks the point at which your body produces its highest amount of LH in one day. This surge happens mid-cycle, usually around day 14 of your monthly cycle. At this point, your body releases LH in response to a rise in estrogen.
The LH surge signals your ovaries to release an egg from one of your follicles. The egg travels through the fallopian tube, where it may be fertilised by sperm if intercourse occurs around this time.
The length of each stage varies from woman to woman and cycle to cycle. For example, some women may only have short luteal phases that last a few days, while others may have longer ones that last up to 1 week or more after ovulation.
Ovulation Predictor Kits (OPKs)
Ovulation Predictor Kits (OPKs) are a common method of tracking ovulation. They work by detecting the hormone luteinising hormone (LH), which increases just before ovulation. You can buy ovulation tests at pharmacies and online. Here are a few things to consider when you’re looking for an ovulation predictor kit:
Cost of ovulation tests
Ovulation predictor kits can be inexpensive, but the price can vary widely depending on the brand, type, and number of tests included. Some kits may be more expensive, but at Fertility2Family, we aim to keep all our OPK and fertility kit bundles low, making them among Australia’s cheapest ovulation tests.
Accuracy and reliability
The most accurate ovulation predictor kits detect LH levels at 25mIU/ml and are unlikely to give false positives. Ovulation tests in Australia have been trailed and tested by the Therapeutic Goods Administration (TGA) to ensure their quality.
Features
Some ovulation predictor kits allow you to see what day of your cycle you’re in at a glance. Others have reminders that tell you when it’s time to take your next reading. You may also want to consider whether the test comes with instructions on using it correctly or if there’s a website to get more information about using it properly.
Ease of use
Some ovulation predictor kits require you to take multiple readings over several days before they become accurate enough. Other tests only require one reading per day and will show an exact date when your peak fertility occurs so that you know exactly when to try having sex.
We suggest using ovulation test strips as they are the cheapest ovulation tests you can buy in Australia and allow you to test as often as needed to detect your ovulation surge.
When Should I Take an Ovulation Test?
OPKs are most helpful for women with a regular 28-day cycle because the peak day for a woman’s LH surge usually occurs on the 14th day of her menstrual cycle (when an egg is released from the ovary). The closer to ovulation you test, the more accurate your results will be.
To get reliable results, you should use the OPKs as follows:
Collect your urine in a clean cup or container between 10 am and 8 pm.
Wipe yourself from front to back before urinating:
- Hold the urine collection cup in one hand and urinate into the container
- Do not use any lubricant on yourself or your fingers (if necessary, wet them with recent urine)
- Make sure you don’t touch anything else — including the inside of the toilet bowl — with your hands after you’ve collected ample.
Wipe yourself with toilet paper afterwards and discard any excess urine in the toilet bowl. Place the absorbent tips of the test stick in your sample.
What Is My LH Level if I’m Not Pregnant?
When you are not pregnant, your level of LH will vary throughout the month.
If your level of LH is not high enough to cause ovulation and pregnancy, you may have hypothalamic amenorrhea. This condition is characterised by a lack of periods for at least three months in women who have not lost a significant amount of weight or who have not stressed their bodies by exercising excessively or restricting calories.
What Is My LH Level if I’m Pregnant?
While LH is present throughout pregnancy, it changes depending on your stage. For example, early in the pregnancy, LH levels are generally low while they peak later during the second trimester and then gradually decrease towards delivery. Knowing your level of LH is important because it can provide insight into the mother’s general health and any potential risks to her baby.
What Can Cause High Levels of LH?
Several different conditions can cause high levels of LH:
Pregnancy
Increased oestrogen and progesterone levels prevent your body from releasing an egg each month. The increase in these hormones causes a rise in your blood LH levels. This rise usually occurs about ten days after ovulation (about two weeks before you expect your period).
Polycystic Ovarian Syndrome (PCOS)
PCOS is a hormonal disorder affecting approximately 1 in 10 women during their reproductive years. The exact cause of PCOS is unknown, but it is believed to occur when high levels of male hormones are produced in the body, which can cause enlarged ovaries and cysts.
Whether you’re just starting your fertility journey or looking to add to your growing family, Fertility2Family is here to help. We know that concepts like ovulation can be complex and difficult to track, so we’re proud to offer a wide range of affordable and accessible fertility products. Browse the full range online today.
Menopause
Menopause, the natural biological process marking the end of a woman’s menstrual cycle, can also cause high levels of LH. As a woman approaches menopause, her ovaries gradually decrease production of estrogen and progesterone. In response, the pituitary gland increases LH production to stimulate the ovaries. This increase in LH can be detected in blood tests and is often a key indicator of the onset of menopause.
Certain Medications
Certain medications can also cause high levels of LH. These include drugs used in fertility treatments, such as Clomiphene and Menotropins, designed to stimulate ovulation. These medications work by triggering the pituitary gland to produce more LH, which stimulates the ovaries to release an egg. While these drugs can effectively treat infertility, they can also elevate LH levels.
Turner Syndrome
Turner Syndrome, a genetic condition that affects only females, can also cause high levels of LH. Women with Turner Syndrome have only one fully functioning X chromosome instead of two. This can lead to various health problems, including premature ovarian failure. When the ovaries fail to produce normal levels of sex hormones, the pituitary gland may produce more LH to stimulate the ovaries, leading to high LH levels.
Congenital Adrenal Hyperplasia
Congenital Adrenal Hyperplasia (CAH) is a group of inherited genetic disorders that affect the adrenal glands. These glands produce a variety of hormones, including sex hormones. In people with CAH, the adrenal glands produce excess androgens or male sex hormones. This can interfere with the normal functioning of the ovaries and lead to high levels of LH.
Luteinized Unruptured Follicle Syndrome
Luteinized Unruptured Follicle Syndrome (LUFS) is a condition where the dominant follicle in the ovary fails to release an egg during the ovulation period, even though other signs of ovulation are present. This can lead to high levels of LH as the body continues to stimulate the ovary to release an egg. LUFS can be a cause of unexplained infertility in women trying to conceive.
Primary Ovarian Insufficiency
Primary Ovarian Insufficiency (POI), or premature ovarian failure, is when a woman’s ovaries stop functioning normally before age 40. Women with POI may have irregular periods or stop having periods altogether and may have difficulty conceiving. High levels of LH can be a sign of POI, as the body tries to stimulate the ovaries to produce eggs.
Hypothalamic Amenorrhea
Hypothalamic Amenorrhea (HA) is a condition where menstruation stops due to a problem involving the hypothalamus. The hypothalamus is a part of the brain that controls the release of hormones necessary for the menstrual cycle. Women with HA often have high levels of LH as the body attempts to stimulate ovulation. This condition can be caused by stress, extreme weight loss, or excessive exercise, making it difficult for a woman to conceive.
Pituitary Tumors
Pituitary tumours, although usually benign, can interfere with the normal functioning of the pituitary gland, leading to an overproduction of certain hormones, including LH. High levels of LH can disrupt the normal menstrual cycle and make it difficult for a woman to conceive. Symptoms of a pituitary tumour can include headaches, vision problems, and unexplained weight gain or loss.
Hyperprolactinemia
Hyperprolactinemia is characterised by an excess of prolactin, a hormone produced by the pituitary gland. High prolactin levels can interfere with the production of other hormones, including LH, and disrupt the menstrual cycle, making it difficult for a woman to conceive. Causes of hyperprolactinemia can include certain medications, thyroid problems, and pituitary tumours.
Support your journey
Understanding and navigating fertility can be complex. Fertility2Family aims to support your journey, providing a wealth of resources in our comprehensive fertility-related blog. Gain insights from our article on ovulation tests and pregnancy, clarifying the intricate interplay of hormones. For a more personal approach, consider our ovulation tests and pregnancy tests, helping you feel confident in your fertility journey. We are with you every step of the way.
Evan Kurzyp
Evan is the founder of Fertility2Family and is passionate about fertility education & providing affordable products to help people in their fertility journey. Evan is a qualified Registered Nurse and has expertise in guiding & managing patients through their fertility journeys.