Can You Get Pregnant with Irregular Periods? Everything You Need to Know 

Does your period show up on schedule every month, or is it more of a free spirit? Most women don’t pay too much attention to their cycle regularity. If you are trying to conceive, however, you may wonder if an irregular period could hinder your chances of getting pregnant.  

The short answer is, yes, your cycle regularity is closely tied to fertility. That doesn’t mean you should start panicking, because irregular periods don’t automatically mean you’re infertile. “An irregular cycle doesn’t mean you can’t get pregnant,” says Lauren M. Beasley, M.D., an obstetrician-gynecologist with Centre Obstetrics and Gynecology in Raleigh, North Carolina. 

 Take a deep breath. Then read on to learn how irregular periods affect fertility and what you can do to move forward. 

What Counts as “Normal?” 

According to the American College of Obstetricians and Gynecologists (ACOG), a regular menstrual cycle lasts between 21 and 35 days, with bleeding typically lasting 2 to 7 days. Your cycle begins on the first day of your period and ends the day before your next one starts. 

According to research, ~74% of women had a usual cycle length of 26 to 34 days, so it’s not abnormal to fall outside of that window. 

H3: What is an Irregular Period? 

Everybody’s cycle is different. But generally, your period is considered irregular if it: 

• Comes too early or too late (less than 21 days or more than 35 days apart) 
• Varies widely from month to month 
• Lasts longer than 7 days 
• Skips altogether (more than 90 days without a period) 
• Comes with significantly heavier or lighter bleeding than usual 

 Also, keep an eye on symptoms like spotting between periods or bleeding so heavy you're soaking through a pad or tampon every hour or two. These are worth bringing up with your doctor. 

Potential Causes of Irregular Periods 

An occasional off-cycle isn’t unusual. A few days late or early could be due to stress, travel, a bad cold, or switching medications. But if irregular periods are common for you, it could point to an underlying condition that may affect fertility.  

 “What’s most important to understand is what is causing the patient to have irregular periods, such as a hormonal issue or a problem with the ovaries,” Dr. Beasley explains. 

Polycystic Ovary Syndrome (PCOS) 

PCOS affects up to 12% of women of reproductive age in the U.S., and it’s one of the most common causes of irregular ovulation and infertility. It’s characterized by high levels of androgens (male hormones), metabolic issues, ovarian cysts, and missed or infrequent periods. 

Thyroid Disorders 

The thyroid gland is a small, butterfly-shaped gland that helps regulate hormones that control ovulation and menstruation. Both hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid) can cause irregular cycles and make it harder to get pregnant. Thyroid imbalance can also impact pregnancy if left untreated. 

Hyperprolactinemia 

Too much prolactin, a hormone best known for stimulating breast milk, can interfere with ovulation and cause irregular or missed periods. 

Premature Ovarian Insufficiency (POI) 

This condition occurs when your ovaries stop functioning normally before age 40. It can lead to irregular periods and reduced fertility, but it's not the same as early menopause. 

Endometriosis 

When uterine-like tissue grows outside the uterus, it can cause painful, heavy periods and interfere with egg implantation or ovulation. 

 If you’re diagnosed with any of the above conditions, your healthcare provider will work with you to develop a treatment plan to support your fertility. 

Can You Get Pregnant with Irregular Periods? 

Yes, you absolutely can get pregnant with irregular periods. But it may be harder to pinpoint when you're ovulating, which can make it more challenging to conceive. That said, many people with irregular cycles go on to have healthy pregnancies. 

How to Boost Your Chances of Getting Pregnant with Irregular Periods 

Irregular cycles can make it challenging to get pregnant, but there are still some things you can do to help your chances. Your diet, exercise and stress levels are all important factors in fertility and your overall health. 

Find a Way to Track Your Cycle That Works For You 

Start marking your period's start and end dates, flow intensity, symptoms, and any other notable details. Over time, you may notice patterns, even if your cycle is unpredictable. Period tracing apps can help. Track the start and end date, flow, cramps and any symptoms (mood changes, nausea, breast tenderness, etc.) 

Watch for Signs of Ovulation 

An irregular period doesn’t mean you aren’t ovulating; you just need to be more diligent in looking for clues of ovulation, such as: 

• Cervical mucus that’s clear, slippery, and stretchy (like egg whites) = your fertile window. 
• Ovulation Predictor Kits (OPKs) can detect the LH surge that happens before ovulation. 
• Basal Body Temperature (BBT) tracking can confirm ovulation after it happens. 

Maintain a Healthy Weight 

Both underweight and overweight people may experience hormone disruptions that affect ovulation. "If you are obese, even losing 5 to 10 pounds of body weight can significantly improve your chances of ovulation and conception,” Dr. Beasley advises. 

Manage Your Stress 

Constant and/or high stress can affect your hormone levels and delay or disrupt ovulation. Look for small ways to unwind each day, such as yoga, journaling, or practicing meditative breathing techniques.  

Have Sex Regularly 

If you’re not sure when you’re ovulating, the best approach is to have sex every 2–3 days throughout your cycle. That way, you’re more likely to hit your fertile window, even if it's unpredictable. 

When to Talk to a Doctor 

If you've been trying to get pregnant for 12 months (or 6 months if you're over 35) without success, it's time to consult a provider. Irregular periods are a key reason to seek support sooner, as they may be a sign of an underlying condition.  

 A healthcare professional is the first step in finding answers: “Blood work and a pelvic ultrasound can help identify the cause so we can treat it and improve your chances of conceiving,” counsels Dr. Beasley. They can also refer you to a fertility specialist, if necessary.  

Bottom Line 

Can you get pregnant with irregular periods? Absolutely. However, it may require a bit more patience, awareness, and support. 

Start by tracking your cycle, watching for signs of ovulation, and making healthy lifestyle changes. And don’t hesitate to reach out to your OB/GYN; they’re your best partner in uncovering the cause of irregularity and mapping out your best path to pregnancy. Your body’s story is still unfolding.