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LH Surge & Detecting Ovulation: Tracking, Symptoms, Intercourse Timing

LH Surge & Detecting Ovulation: Tracking, Symptoms, Intercourse Timing

Luteinizing hormone (LH) is one of the most important hormones controlling the phases of your menstrual cycle. A sudden surge in LH level marks the beginning of the ovulatory phase, resulting in the release of an egg from the ovary. If you are trying to get pregnant, you can determine your fertile window by understanding how long after this surge in the LH do you ovulate.

This article will discuss LH levels in ovulation, how to track LH surge, and how to interpret your fertile window. Ovulation test from Fertility2Family can help you track the LH surge and help pinpoint the most fertile time during your menstrual cycle.

LH Surge peak ovulation

Luteinizing hormone, an LH surge?

Luteinizing hormone is a fertility hormone secreted by the Pituitary gland. The levels of LH are fairly steady throughout your menstrual cycle, except just before you ovulate. A sudden and dramatic increase in the LH surge leads to the release of an egg from the ovary.

The time in your menstrual cycle before the release of the egg is called the Follicular phase. A few of the ovarian follicles grow and develop and get ready to release an egg during this phase. As the cycle progresses, one of the follicles becomes dominant and fully matures. A sudden surge in the LH triggers this mature follicle to fuse with the ovarian wall and release the egg, marking the end of the follicular phase and the beginning of the ovulation phase.

After ovulation, the released egg travels down the fallopian tube toward the uterus. The egg is viable for about 24 hours, meaning that fertilization with sperm can be possible only in this 24-hour window. If the sperm fails to fuse with the egg during this time, the egg dies and eventually sheds off along with the menstrual flow.

Although the egg is viable for only 24 hours, a man’s sperm can be viable for up to 5 days in the female reproductive tract. Hence, your fertile window is counted as five days before you ovulate and the day of ovulation itself. If you have intercourse during these days, the chance of you getting pregnant is maximum.

Estrogen and LH surges

The secretion of another fertility hormone called estrogen starts a few days after the end of your menstrual period. Estrogen is an important hormone as it helps the endometrium of the uterus to get ready to receive the fertilized egg. The endometrial layer of the uterus thickens under the influence of this hormone. The uterus produces a lot of mucus that makes the environment conducive for the travelling sperm.

An increase in estrogen level in conjunction with the surge in LH is a good indicator of your fertile window. The estrogen level starts to rise about 4-5 days before ovulation, and the LH surge happens on the day of ovulation. Hence, both these hormones can help in predicting the fertile window of your body

Your fertility increases as you approach your ovulation, and so does the level of estrogen in your body. The rise in estrogen triggers the pituitary to suddenly release a large quantity of LH, resulting in the phenomenon called ‘The LH surge’ and causes the release of an egg from the ovary.

The level of LH during the surge goes up suddenly but briefly. Every woman is different, and the time for which the LH surge lasts can be different for different women. Hence, the surge goes unnoticed when testing with ovulation strip tests.

The amount of LH in the body during the LH surge varies a lot between women as well. According to a study, the concentration of LH during the surge can be between 20 IU/L to 75 IU/L. Many ovulation predictor kits can’t detect the lower level of the LH and hence, can completely miss the LH surge. Fertility2Family Home Ovulation tests are 99% accurate in predict ovulation in various laboratory studies, making them very reliable in predicting your fertile window.

How long after LH surge do you ovulate?

In many women, ovulation occurs 24-36 hours after the LH surge; once the ovaries release the egg, the level of LH declines sharply.

The menstrual cycles of different women are different. Accordingly, some women can ovulate as early as the 8th day of their process, while others ovulate as late as the 21st day. However, most women ovulate around the 14th day of their cycles.

Making a note of your period every month is not enough to predict the time of ovulation. Even if you have a regular menstrual cycle, it might take as much as a year of continuous logging to predict your ovulation with a certain degree of confidence.

How long does LH surge last?

The LH surge lasts for just about two days but can be as short as 10 hours long. If you are trying to get pregnant, it is important to track your LH surge and track it concerning your ovulation.

A rise in estrogen level before ovulation marks the beginning of your fertile window. You are at our peak fertility during the LH surge. If the fertilization does not happen within the 24-hour window after ovulation, the chances of pregnancy decrease to zero.

Some experts also advise tracking your basal body temperature (BBT) to predict your LH surge, hance ovulation, and fertile window. That said, BBT increases 12-24 hours after ovulation, and you stand a chance of missing the ovulation completely if you use the BBT method alone to track your fertility window. BBT and ovulation tracking kits from Fertility2Family are the best ways to predict the fertility window with a greater degree of accuracy.

Best ways to track estrogen and LH levels and predict ovulation

You can test LH and estrogen levels using multiple ways-

    • Laboratory test- It is the most accurate method as it detects the level of estrogen ad LH directly in your blood. That said, the test must be done at the doctor’s office and requires a blood sample collection. If you are trying to conceive, you might need to get the test done as many as 10-15 times a month which is inconvenient and, more importantly, expensive.
    • Testing at home with easy home ovulation tests – A positive ovulation predictor kit (OPK) test means that you have higher LH levels than the test, Our tests detect surges over 25mIU/ML which allows for the most accurate detection of your LH surge. OPKs use a highly sensitive method to detect even a small quantity of LH so that you don’t miss the LH surge and can predict your ovulation with accuracy.

When should you test for ovulation?

Whether you are trying to conceive or trying to avoid pregnancy, ensure to test the LH levels early in the menstrual cycle. As your cycle can change in duration and ovulation time, starting to test early will reduce the risk of missing the fertility window.