What Are the Chances of Getting Pregnant With Irregular Periods?

Health Professional


I have a very irregular menstrual cycle. For example, it has been approximately 42 days since the start of my last period, and there seems to be no new period on the horizon. What are the chances that I could get pregnant?



First of all, congratulations on your new marriage! It sounds like you and your partner are starting to think about having a family. Having a baby is a decision that is not to be taken lightly, so I applaud you for thinking seriously about it beforehand.

Reasons for delayed periods

You might even be wondering, since your period is so delayed, if there is a chance that you have already conceived. There are a number of reasons that your period could be delayed that are not related to pregnancy. The majority of these would need to be diagnosed by your doctor or midwife.

The general conclusion is that a normal menstrual cycle is between 24 and 38 days. You are just outside of that range. This means that getting a physical exam may be helpful in determining why your period is tardy. Your practitioner will have a few helpful tricks up their sleeve, from watchful waiting to perhaps medications designed to reset your cycles, to help get you back into a “normal-for-you” pattern.

One strategy your practitioner might suggest are various forms of birth control, although this is obviously not ideal if you are trying to start a family. Yet, hormonal birth control options often make your periods more predictable. If you have had heavier periods, you may notice they are lighter on birth control too. Still, be sure to discuss with your doctor when you can expect your period. Some forms of birth control may make your periods even further apart or completely absent, but this is intentional. If you are planning on trying to conceive, there are other options you can discuss with your doctor beyond birth control.

Sometimes, your period is delayed because you are indeed pregnant. If you’re showing no other typical signs of pregnancy, there may be a problem with the pregnancy, like an impending miscarriage. Your doctor can help you figure out if that’s the case. This typically does not impact your future fertility.

Planning for pregnancy with irregular periods

If you have a clean bill of health and you are ready to start thinking about having a family, you will want to discuss why your period was delayed with your doctor, and get a general physical for both you and your partner. This can help you get pregnant as quickly as possible and ensure you remain as healthy as possible through the entire gestation.

You’ll notice that I said “you and your partner.” Did you know that your partner’s health greatly contributes to your chances of getting pregnant and the health of the baby? It can also be a time to try to diagnose and treat any potential male fertility issues.

Your doctor can help determine the cause of your delayed or irregular periods and may be able to help you treat the problem. For example, one of the most common causes of infertility is polycystic ovary syndrome (PCOS). People with PCOS often have irregular periods. Certain treatments for PCOS are targeted toward normalizing your menstrual cycle, which can help you conceive. Many people with PCOS or other issues causing irregular cycles go on to conceive healthy babies.

Once you are back on track with your menstrual cycle, can I recommend that you consider tracking your periods with one of these handy fertility and period trackers? This can help alert you in the event that you have issues like a delayed period again. Tracking thisinformation can really help you in getting the appropriate healthcare, especially if you’re looking to conceive.

There are a lot of what-ifs with a delayed menstrual cycle. The good news is that a physical exam can usually provide you with some quick answers. I hope that you’ll consider seeing your practitioner and getting some answers soon so you can move forward in starting your family. Good luck!

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You should know: The answer above provides general health information that is not intended to replace medical advice or treatment recommendations from a qualified healthcare professional.

See more helpful articles:

Seeing Your Doctor for Preconception Care: What to Expect

Infertility: Causes, Diagnosis, and Treatments

10 Facts You Should Know If You Are Trying to Get Pregnant