Hormones play a vital role in all phases of the menstrual cycle and reproductive process. An essential hormone that you may hear discussed quite often when navigating the trying to conceive (TTC) world is luteinizing hormone (LH). This particular fertility hormone is responsible for triggering the ovaries to release an egg each month (i.e., ovulation) and even helps support early pregnancy.
What is a normal LH level?
Unfortunately, there’s no black and white answer for a ‘normal’ LH level. LH levels vary from woman to woman and fluctuate depending on what part of your cycle you’re in. By testing for LH with the Premom quantitative ovulation prediction kits (OPKs), you can see your exact number of LH when paired with the Premom app.
Follicular phase (first day of your period until ovulation)
Before ovulation, levels of LH tend to be lower around 1.9-14.6 IU/L.
Midcycle near ovulation
This is where we are looking for that LH surge to indicate ovulation is approaching. Once you see your LH peak (highest level of LH), you can assume ovulation will occur in the next 24-36 hours. A surge to trigger ovulation can result anywhere from 12.2-118 IU/L – see what a huge range that is? This is why it’s so important to consistently track so you can see your baseline levels and what is ‘normal’ for you!
Luteal phase (after ovulation until your next period)
After ovulation, your LH tends to fall back to baseline similar to the follicular phase of your cycle. A range of 0.7-12.9 IU/L is considered healthy.
As you can see, there’s a wide range of what is considered ‘normal.’ Your body is unique, so it’s not recommended to compare your LH levels to someone else’s, but rather track your LH consistently throughout your cycle to see what is normal for you and identify a pattern.
If compared, you may notice that your baseline is much lower than your friend’s, so your surge that triggers ovulation will likely also be lower – both are common scenarios that do not necessarily indicate any cause for concern. If you know your consistent baseline each cycle, you are more apt to notice abnormal LH levels.
What can cause abnormal LH levels?
Low
- Malnutrition
- Pituitary gland or hypothalamus dysfunction
- Postmenopause
High
- Obesity
- Polycystic ovarian syndrome (PCOS)
- Perimenopause
Some women experience abnormally high or low levels of LH and it’s possible that those results are related to an underlying condition. When your LH is out-of-range, it also affects your other hormones. When TTC, monitoring your LH level can not only help you get pregnant faster, it can help you discover fertility issues much quicker.
Since LH is secreted from the pituitary gland and regulated by the hypothalamus, there is a direct relationship between low LH levels and dysfunction of either part of the brain.
Women with PCOS tend to see higher baseline levels of LH each cycle. The absence of a significant LH surge is what contributes to anovulation.
Perimenopausal women are likely to see a drastic increase in LH followed by a gradual decline during the postmenopausal period.
How to easily monitor your LH levels
To ensure you are tracking your LH levels efficiently:
- Utilize ovulation predictor kits (OPKs)
- Test LH daily after your period ends
OPKs are effective at detecting your LH surge. Studies have shown that using ovulation tests increase chances of pregnancy by two menstrual cycles compared to those who do not use ovulation tests. By testing daily between 10am-8pm starting the day after your period ends, you will be more likely to identify your LH peak while also ensuring you do not miss it with inconsistent testing. Aim to test for at least 5 consecutive days per cycle – consistency, consistency!
Take some of the guesswork out of interpreting your LH levels by logging them into your Premom app! Premom’s in-app camera makes reading your ovulation tests and identifying your unique patterns easy. Premom generates a user-friendly chart throughout your cycle and enables you to see if there’s a consistent low or high LH or if you never have an LH surge.
If you have been following all of these tips while tracking for a few cycles and are still having difficulty understanding your LH patterns, always feel free to reach out to your doctor for a blood LH test. Your doctor may want to do multiple blood tests during various phases of your cycle for a full picture.
Don’t hesitate to schedule a virtual consultation with any of our medical providers through your Premom app. We are here to support your TTC journey and aim to equip you with the knowledge to get pregnant faster!
References
- Full article: Luteinizing hormone and human chorionic gonadotropin: distinguishing unique physiologic roles (tandfonline.com)
- LH – Overview: Luteinizing Hormone (LH), Serum (mayocliniclabs.com)
- (PDF) Development of the first urinary reproductive hormone ranges referenced to independently determined ovulation day (researchgate.net)
- The Pituitary Gland and Hypothalamus – Anatomy & Physiology (hawaii.edu)
- Luteinizing Hormone (Blood) – Health Encyclopedia – University of Rochester Medical Cente
