Late ovulation is when ovulation occurs after day 21 in your cycle. Here’s why and when late ovulation might occur, and what it means for your fertility.
As much as we’d like our menstrual cycles to be consistent and regular, sometimes they fall out of whack. Just like our period sometimes comes earlier or later than we expect it to, ovulation can happen earlier or later, too. When ovulation happens after day 21 of your menstrual cycle, it’s late ovulation.
While everyone experiences changes in their menstrual cycle, is late ovulation something to worry about? What’s behind it, and how can it affect your chances of getting pregnant? Here’s what you need to know.
What is late ovulation? Late ovulation is when ovulation occurs after day 21 of your cycle. In a typical 28-day cycle (which only 13% of people with menstrual have!), ovulation typically occurs around day 14. Ovulation is the midpoint of your cycle, so if it happens after more than 3 weeks of your cycle, it’s considered late.
Causes of late ovulation Many factors can cause late ovulation—some are temporary and manageable, and others are underlying conditions that may need specific treatment.
Stress Late ovulation can be your body’s reaction to a particularly stressful time. When you’re under stress, your body activates the sympathetic nervous system and the Hypothalamic-Pituitary-Adrenal Axis (HPA). When the HPA is activated, it leads to increased hormonal production, which can interfere with the normal production of reproductive hormones like estrogen and luteinizing hormone (LH) .
This hormonal disruption can delay or even prevent ovulation.
Both short-term acute stress (like a work deadline or family emergency) and chronic stress can affect your cycle this way and lead to late ovulation.
Exercise and body weight changes You need a certain amount of body fat to maintain regular ovulation—that’s because fat cells produce a tissue with an enzyme that helps convert androgens into estrogen. Essentially, fat cells help you produce estrogen, and you want to make sure you don’t have too little or too much.
Exercise and body weight changes can affect this balance:
Over-exercising can reduce body fat below the threshold needed for regular ovulationSudden increases in intense exercise can stress your body, causing hormonal changesRapid weight changes can signal to your body that it's under stress (and stress, as we know, can delay ovulation!)Medical conditions Late ovulation may be a result of lifestyle changes like stress and exercise; however, there are some underlying medical conditions that can lead to late ovulation, too.
Polycystic Ovary Syndrome (PCOS) : this condition causes hormonal imbalances that impact ovarian function, including causing irregular cycles and late ovulationThyroid disorders: both hypothyroidism and hyperthyroidism can interfere with the hormonal signals needed for timely ovulationEndometriosis : this condition can also cause hormone imbalances that affect the timing of ovulation, as well as cause inflammation and scar tissue that impact the release of eggsMedications Sometimes, the medications you take can also affect ovulation timing. For example, if you’ve recently stopped using hormonal birth control, your body may take several months to start ovulating regularly.
>>RELATED: What Are Signs of Ovulation After Stopping the Pill?
Other medications that can affect ovulation timing include:
Anti-inflammatory drugs Certain antihistamines Antidepressants Breastfeeding While breastfeeding, your body produces higher levels of prolactin, the hormone responsible for milk production. High prolactin levels can suppress ovulation or make it irregular. This is your body's natural way of spacing pregnancies—though just how much ovulation is naturally suppressed varies from one person to the next, and decreases as you start to breastfeed less frequently.
>>MORE: 7 Signs of Ovulation While Breastfeeding
Age-related changes As you age and reach perimenopause , ovulation can become less predictable. That’s because your estrogen and progesterone levels are declining, affecting your menstrual cycle and eventually leading to the end of your period and fertile years. Your cycles may become more irregular—including late ovulation.
Does late ovulation affect my chances of conceiving? Late ovulation doesn’t necessarily mean you can’t get pregnant—it just may make the process of trying to conceive a bit harder.
Late ovulation still means that you’re ovulating, and you need to ovulate to get pregnant. However, late ovulation makes timing having sex to get pregnant more challenging, because your fertile window shifts later than usual. If you’re using a calendar estimate to try and figure out when you’re ovulating, you’ll miss your fertile window if you end up ovulating late.
How to track late ovulation So, how can you optimize when you’re trying to conceive when you may be dealing with late ovulation?
First, you can look out for typical physical signs of ovulation . For example, you can look for changes in your cervical mucus—specifically, consistency that’s clear and stretchy—or take your basal body temperature to see if it’s dipped, then risen about a half a degree.
While these signs are a good starting point to trying to figure out when you’re ovulating, they’re far from precise. What happens if you take your temperature at an inconsistent time, or you don’t see that your cervical mucus is different until too late?
The best way to know exactly when you’re ovulating is by measuring your hormone levels. Right before you ovulate, you experience an LH surge that triggers the release of the egg. At-home hormone tests like the Oova kit allow you to measure your specific hormone levels from the comfort of your own bathroom, then see how your hormones fluctuate over the course of a cycle. You’ll be able to see your LH surge in the Oova app and pinpoint exactly when you’re ovulating—even if you’re experiencing late ovulation.
When to see a healthcare provider about late ovulation Late ovulation isn’t always cause for alarm. You might have a delay in ovulation because of everyday stress, and it might be a one-time thing.
While late ovulation often resolves on its own, there are times when it's worth consulting a healthcare provider:
If you've been trying to conceive for a year without success (or 6 months if you're over 35) If your cycles are consistently longer than 35 days If you experience very irregular periods or skip periods entirely If you have other symptoms like unusual hair growth or significant weight changes A healthcare provider can help you figure out if there’s an underlying medical condition that might be affecting when you ovulate, and give you further guidance on conception if late ovulation is affecting your ability to get pregnant.
Late ovulation: the bottom line Late ovulation is when you ovulate after day 21 of your cycle. Often, late ovulation is part of a normal variation in your cycle that might happen due to a lifestyle factor like stress or a change in exercise routine. Sometimes, late ovulation happens because of an underlying medical condition or a medication you’re taking.
If you’re trying to conceive while having late ovulation, don’t worry—conception is still possible! You’re still ovulating, but the timing is different from the usual 28-day, 14-day ovulation standard. Instead, you’ll need to track ovulation symptoms or your hormone levels to understand when your fertile window is.
If late ovulation continues to impact your conception, you have other cycle irregularities, or you have other symptoms that accompany late ovulation, a healthcare provider can help guide you—in both your fertility journey and for your overall well-being.
