Perimenopause and Pregnancy: What You Need to Know About Fertility, Risk, and Contraception

Your periods have become irregular. You're having hot flashes. You're not sleeping well. You've started to wonder whether perimenopause means your reproductive years are behind you.

Here's what many people don't know: perimenopause and fertility overlap far more than most expect. You can absolutely get pregnant during perimenopause. Irregular periods are not the same as no ovulation. A fertility decline is gradual, not a switch that flips. And the symptoms of early pregnancy and perimenopause are so similar that each is regularly mistaken for the other.

This article covers the real picture: how fertility changes during this transition, what the risks look like, how to approach contraception, and what options exist if you want to conceive.

Perimenopause symptoms and early pregnancy look almost identical

This is not a coincidence. Both involve significant hormonal changes that affect the same systems.

Missed or irregular periods, fatigue, breast tenderness, mood changes, bloating, disrupted sleep, increased urination, brain fog: all of these are common in both early pregnancy and perimenopause. Many women assume their missed period is a sign of perimenopause and skip the pregnancy test entirely.

If you are in your 40s, your periods have changed, and there is any chance you could be pregnant, take a pregnancy test. Home urine tests work reliably during perimenopause. Don't let the assumption that "it's probably hormones" prevent you from ruling out pregnancy, which requires a very different kind of attention and care.

Nausea is one symptom worth flagging specifically. It's common in early pregnancy and less commonly associated with perimenopause, though it does occur. If you have missed a period and are also experiencing nausea, treat this as a reason to test rather than a reason to assume it's hormonal.

The overlap in symptoms also runs the other direction. Women who are in early perimenopause sometimes worry they are pregnant when they are not, because the physical sensations are genuinely similar. A test removes the guesswork.

Yes, you can get pregnant during perimenopause

Perimenopause does not mean you are no longer fertile. Fertility declines during this transition, but the decline is gradual and uneven. You are still ovulating during perimenopause, though less predictably than before.

The challenge is that ovulation becomes harder to predict. Your cycles lengthen, shorten, or skip entirely, but any given cycle may still include ovulation. You cannot know from symptoms or cycle pattern alone whether you ovulated in a given month.

Ovulation predictor kits (OPKs), the same tests sold for people trying to conceive, detect the LH surge that precedes ovulation. They work during perimenopause, though the results can be harder to interpret because LH levels are more variable and sometimes elevated even outside ovulation. If you are actively trying to conceive, working with a reproductive endocrinologist gives you much more precise information than OPKs alone.

Statistical fertility is lower during perimenopause than in your 20s or 30s. But lower probability is not zero probability. Unintended pregnancies in women in their 40s are more common than most people expect, and many of them occur in women who assumed they were past the point of needing contraception.

If pregnancy is not your intention, you need reliable contraception throughout perimenopause, up until you have been confirmed postmenopausal for 12 consecutive months. Your doctor can confirm postmenopausal status. Self-assessment based on symptoms is not reliable enough for this decision.

Tracking your cycle carefully, including noting length, flow, and any midcycle symptoms, gives you and your provider useful data regardless of whether you're trying to conceive or trying to avoid it. PeriPlan's cycle tracking is designed for exactly this kind of irregular, perimenopause-specific pattern.

Contraception during perimenopause

The contraception question during perimenopause has two layers: effectiveness and health suitability.

Combined hormonal contraceptives (pill, patch, ring) are highly effective and have the added benefit of regulating irregular periods and reducing hot flashes for some women. However, combined estrogen-progestogen contraceptives carry increased cardiovascular and clot risk with age, particularly for women who smoke, have high blood pressure, migraines with aura, or other cardiovascular risk factors. Many providers recommend switching to progestogen-only or non-hormonal options by age 40 to 50.

Progestogen-only pill (mini pill) is effective and generally well-tolerated. It doesn't carry the same cardiovascular risks as combined pills and may help regulate irregular bleeding. It requires consistent daily timing.

Hormonal IUDs (Mirena, Kyleena) are among the most convenient options during perimenopause. They provide continuous contraception, often reduce or eliminate periods (which many perimenopausal women welcome), and the levonorgestrel they release has minimal systemic effect. A Mirena IUD inserted in your 40s may provide contraception through menopause without needing replacement.

Copper IUD provides highly effective non-hormonal contraception for up to 10 years. It's suitable if you want to avoid any added hormones. It can increase menstrual bleeding, which may be less welcome if your periods are already unpredictable.

Barrier methods (condoms, diaphragm) provide no hormonal effect and are appropriate at any age, but their effectiveness depends more heavily on consistent use.

Important note: Hormone replacement therapy (HRT) used to manage perimenopause symptoms is NOT a contraceptive. If you're using HRT, you still need a separate contraceptive method until confirmed postmenopausal. Your healthcare provider can help you navigate both simultaneously.

If you want to conceive during perimenopause

Choosing to try to conceive in your 40s is increasingly common, and the medical landscape for supporting this has expanded significantly. Here is a realistic picture of what that path looks like.

Natural conception becomes less likely but is not impossible. Egg quality and quantity both decline with age, which is the primary driver of reduced fertility in the 40s. But pregnancy does occur. Women in their early 40s have a roughly 10 to 20 percent chance per cycle with unassisted conception. By the mid-to-late 40s, this drops considerably, though the exact numbers vary by individual.

Egg freezing timing. If you are in your late 30s or early 40s and considering pregnancy in the future, egg freezing offers the best outcomes now rather than later. Egg quality declines with age more significantly than most people expect. Eggs frozen at 38 or 39 have meaningfully better outcomes than eggs frozen at 43. If this path is on your radar, early conversation with a reproductive endocrinologist gives you the most options.

IVF with your own eggs. IVF success rates with your own eggs in the mid-to-late 40s are lower than in earlier years, and multiple cycles are often needed. Your reproductive endocrinologist can measure your ovarian reserve (via AMH blood test and antral follicle count) to give you a more personalized picture of your current fertility.

IVF with donor eggs. Using donor eggs from a younger donor largely removes the age-related egg quality barrier. IVF with donor eggs has relatively consistent success rates well into the mid-40s and even beyond. For women who are open to this option, it often represents the most reliable path to pregnancy after 44 or 45.

Preconception health matters more at this stage. Optimize sleep, nutrition (especially folate from food and supplemental folic acid), protein intake, blood sugar regulation, and stress load before trying to conceive. Underlying thyroid function, which can be disrupted by perimenopause, should be checked. Your provider can assess any other factors relevant to your individual health history.

Pregnancy risks in perimenopause are higher

Choosing to conceive in your 40s is a valid decision, but a fully informed one includes understanding the elevated risks.

Chromosomal abnormalities in the fetus are more common with older eggs. The risk of Down syndrome, for example, rises from about 1 in 1,000 at age 30 to roughly 1 in 100 at age 40 and higher after that. Prenatal genetic testing (including NIPT, chorionic villus sampling, and amniocentesis) is typically recommended.

Miscarriage rates are higher. Approximately 40 to 50 percent of pregnancies in women over 40 end in miscarriage, most due to chromosomal issues. This is not a reflection of your body failing. It is a biological reality about egg quality and chromosomal stability at this age.

Pregnancy complications including gestational diabetes, preeclampsia, and placenta previa occur at higher rates in pregnancies over 40. These are manageable with appropriate monitoring, but they mean your pregnancy will typically be treated as higher risk and followed more closely.

Postpartum recovery may be different. Some women in their 40s find postpartum recovery more physically demanding, especially if perimenopause symptoms are also present. Having a clear support structure in place before the birth is worth planning.

These risks don't make pregnancy in perimenopause the wrong choice. They make it a choice to make with clear information and close medical guidance.

Navigating HRT and contraception at the same time

One of the most confusing situations women in perimenopause face is managing both hormone therapy for symptoms and contraception for fertility. These are two separate things, but they're often conflated.

Hormone replacement therapy (HRT), whether estrogen alone or combined estrogen and progesterone, is prescribed at doses designed to relieve symptoms. These doses are lower than the doses in hormonal contraceptives and are not calibrated to suppress ovulation. This is a critical distinction. Taking HRT does not mean you are protected from pregnancy.

If you are using HRT and have not yet reached confirmed menopause, you need a separate contraceptive method. The most compatible options are non-hormonal: a copper IUD, barrier methods, or (if applicable) surgical methods. Some providers also recommend a low-dose progestogen-only pill alongside HRT, since the progestogen in HRT is often different from contraceptive progestogen and at a different dose.

What to tell your provider: If you are in perimenopause and want to start HRT, bring up contraception explicitly in the same conversation. Many women are not proactively counseled on this. Ask directly: what contraceptive method is compatible with the HRT you're recommending for me?

The progesterone component of HRT is not always the same as contraceptive progestogen. Some women assume the progestogen in combined HRT provides contraception. It does not in most cases. Only micronized progesterone (Utrogestan) and a handful of synthetic progestogens at specific doses have evidence for contraceptive effect, and even then, the safety and reliability data is limited compared to dedicated contraceptive methods.

The overlap between HRT and contraception is genuinely confusing, and it's worth taking the time to get a clear answer from your specific provider about your specific situation.

When can you stop using contraception?

This is one of the most commonly asked questions about perimenopause, and the answer is more specific than most people expect.

The standard medical guidance: you can stop contraception after 12 consecutive months of no periods if you are over 50, or after 24 consecutive months of no periods if you are under 50. These thresholds reflect the time it takes to confidently confirm that ovulation has stopped.

There is no shortcut. Going six months without a period does not mean you are done. Going nine months without a period does not mean you are done. Until you hit the specific threshold that applies to your age, with no period in between, the guidance holds.

Many women reach confirmed menopause between 49 and 53. If your last period was at 48 or 49 and you are now 50, you still need to wait for the 12-month mark from that final period, not from your birthday. Your age at a given point and when your final period occurred are separate data points.

FSH (follicle-stimulating hormone) blood tests are sometimes used to assess menopausal status, but they are not reliable on their own for contraception decisions in women using hormonal contraception. Hormonal methods suppress FSH, so a low FSH reading on the pill doesn't confirm you're still fertile. Stopping hormonal contraception to check a "true" FSH requires a gap of at least several weeks, during which alternative contraception should be used.

Do not use symptom frequency or cycle pattern alone to decide you no longer need contraception. The only reliable indicator is the 12-month or 24-month period-free threshold confirmed with your healthcare provider.

This is an important conversation to have directly with your doctor. They can review your individual history, any hormone therapy you're using, and give you a recommendation that's accurate for your specific situation.

This content is for informational purposes only and does not replace medical advice. Always consult your healthcare provider about your specific situation.