Fertility In Perimenopause | Odds, Options And Timing

You might have heard that once periods start to change, natural pregnancy is finished. In reality the picture is more mixed. Egg numbers and quality fall, yet the ovaries can still release eggs at irregular times, which means both wanted and unwanted pregnancies can happen until menopause is complete.

Fertility In Perimenopause: What Actually Happens

Perimenopause is the transition phase before menopause, when hormone levels start to fluctuate and periods become less predictable. Many people enter this phase during their forties, though it can start a little earlier or later. During this time your body is still producing estrogen and progesterone, just in a more uneven pattern than before.

Ovulation becomes irregular instead of monthly. Some cycles have a strong egg release, others have none. That is why you might notice stretches with no period followed by a heavy bleed, or spotting that feels out of character. Medical groups such as the American College of Obstetricians and Gynecologists describe this as a normal shift in the way the ovaries respond to brain hormones that control the menstrual cycle.

The main point is that irregular cycles do not always mean you have stopped ovulating. As long as ovulation occasionally happens, pregnancy is still possible, even if the odds are lower than they were in your thirties.

Perimenopause Fertility Chances By Age

Data shared by the American Society for Reproductive Medicine in its Age And Fertility booklet shows that a healthy person in their early thirties may have around a 20 percent chance of conception in a given month. By about age forty that figure drops to below 5 percent per cycle, and miscarriage risk also rises with age.

An article titled Perimenopause: Pregnancy Risks notes that the annual chance of pregnancy at ages forty to forty four is roughly 30 percent if no contraception is used, falling to around 10 percent between forty five and forty nine. At the same time, live birth rates at the far end of the reproductive years become very low, which reflects both lower conception rates and higher miscarriage risk.

How Hormone Changes Affect Ovulation

During perimenopause, levels of follicle stimulating hormone rise as the brain tries harder to prompt the ovaries to grow follicles. Estrogen and progesterone surge and dip instead of following the familiar monthly pattern. A perimenopause overview from Cleveland Clinic notes that this stage can last several years and bring symptoms such as hot flushes, sleep problems, mood changes, and vaginal dryness.

Some cycles still include a mature follicle and an egg release. Others stall partway, leading to a bleed without ovulation. Because the timing of that egg release becomes less predictable, a single unprotected act of intercourse can, on some days, still lead to pregnancy even after several months of no periods.

Certain health conditions and medications can influence ovulation during perimenopause. Thyroid disease, high body mass index, smoking, past pelvic surgery, and some cancer treatments can all reduce egg reserve or interfere with hormone signaling. If any of these apply to you, it is worth raising them with your doctor when you talk about your plans.

Signs You May Still Be Ovulating

Cycle Patterns

Even if periods are irregular, a bleed that arrives after two to six months and feels like a full period can signal that ovulation sometimes occurs. Spotting alone is less reliable as a sign. The menopause symptoms guidance from the NHS notes that changing period patterns are a standard part of perimenopause, so new irregularity does not automatically mean fertility is gone.

Cervical Mucus Changes

Mucus that becomes clear, slippery, and stretchy for a few days suggests that estrogen has risen enough to prepare for ovulation. This sign can still appear during perimenopause, just not always on the same cycle day.

Ovulation Predictor Kits

Luteinizing hormone urine kits can at times still pick up a surge during this stage. False positives or confusing patterns are more common than in younger years, so a kit works best when combined with tracking of bleeding and mucus changes rather than used alone.

Age Range	Cycle Pattern	Approximate Pregnancy Chance*
Early 30s	Regular ovulation most months	About 20% per cycle
35–37	Cycle length may shorten slightly	Around 15% per cycle
38–40	Early perimenopause for some people	Roughly 5–10% per cycle
40–44	Irregular ovulation, skipped periods	About 30% per year without contraception
45–49	Longer gaps between bleeds	About 10% per year without contraception
45–49 (live birth)	Ovulation rare and egg quality lower	Well under 1% chance of live birth
50 and above	Periods usually stopped; menopause approaching or reached	Pregnancy very uncommon, but not impossible until menopause confirmed

*Figures are rounded estimates from population studies, not guarantees for any one person.

Trying For Pregnancy During Perimenopause

Start With A Preconception Visit

A doctor or midwife can review your medical history, medicines, family risks, and past pregnancies, then suggest tests that match your situation. Blood pressure checks, screening for diabetes or thyroid disease, and up to date cervical screening all help lower avoidable risks before you try to conceive.

Time Intercourse Around Possible Ovulation

Because cycles are unpredictable, it helps to stay sexually active regularly across the month rather than waiting for a perfect sign. A common suggestion is intercourse every two to three days when pregnancy is the goal. Simple tracking of bleeding dates and mucus changes can add more insight without turning sex into a timetable exercise.

Look After General Health

Healthy body weight, a pattern of movement that you enjoy, a varied diet, limited alcohol, and no smoking all help fertility and pregnancy outcomes at any age. If you use hormone therapy for perimenopausal symptoms, your doctor can talk through whether adjustments are needed while you try to conceive.

Know When To Ask About Fertility Testing

Guidelines from reproductive medicine groups often suggest asking about testing after six months of trying at age thirty five or older, and sooner in the early forties. Tests may include ovarian reserve markers, semen analysis, and checks for conditions such as fibroids or endometriosis that can lower the chance of conception or increase miscarriage risk.

When You Want To Avoid Pregnancy

Many people in perimenopause are more worried about surprise pregnancy than about difficulty conceiving. Because ovulation can still happen without warning, contraception remains relevant until menopause.

Public health groups advise staying on contraception for at least one year after your final period if that period happens at age fifty or over, and for two years after the last period if it stops earlier than fifty. This accounts for the fact that ovulation can still occur in the first year after bleeding stops.

Options include barrier methods, intrauterine devices, implants, and some hormonal pills. A clinician can help match a method to your health profile and symptoms. For people using hormone therapy for hot flushes and other symptoms, it is worth clarifying whether the specific preparation also acts as contraception, because some forms do not protect against pregnancy on their own.

If pregnancy would be unsafe for medical reasons, such as severe heart disease or advanced kidney disease, your team may recommend stronger or dual methods of contraception until menopause is clear.

Treatment Options When Pregnancy Is Hard To Achieve

If you have been trying for some time without success, or if tests show low ovarian reserve, fertility treatments may be part of the conversation. Treatment choices depend on age, test results, how soon pregnancy is desired, and personal values.

Option	Who It May Suit	Things To Know
Timed Intercourse	Regular partner, some ongoing ovulation, no major fertility factors	Uses simple tracking and sometimes low dose medicines to help ovulation.
Ovulation Induction	Irregular or absent ovulation with open fallopian tubes	Tablets or injections stimulate egg growth; ultrasound monitoring checks response.
Intrauterine Insemination (IUI)	Mild sperm issues or use of donor sperm	Processed sperm placed in the uterus around ovulation, often with stimulation.
In Vitro Fertilisation (IVF)	Tubal factor, unexplained infertility, older age with fair ovarian reserve	Eggs collected after stimulation and fertilised in a lab, then embryos transferred.
IVF With Donor Eggs	Very low or absent ovarian reserve, very high miscarriage risk with own eggs	Donor eggs tend to bring higher success rates in the later forties than own eggs.
Embryo Donation	Couples or single parents open to embryos created by others	Often used when both egg and sperm factors are present.
Adoption Or Fostering	Those who wish to parent without pregnancy	Processes vary by country and involve legal, practical, and emotional steps.

Success rates for treatments that use your own eggs fall with age because egg quality is lower in the perimenopausal years. Clinics often share age specific success statistics, and many people in their mid to late forties who conceive with help do so with donor eggs rather than their own.

Questions To Raise With Your Doctor

If You Hope To Conceive

• Do my current periods and symptoms suggest that I am still ovulating?
• Are there tests you recommend before I try to conceive, based on my age and health history?
• How long should I try naturally before we talk about fertility treatments?
• Are any of my current medicines unsafe in pregnancy, and if so, what alternatives are available?

If You Want To Avoid Pregnancy

• Given my health, which contraceptive methods are suitable during perimenopause?
• Does my menopausal hormone therapy give any pregnancy protection?
• When can I safely stop contraception based on my age and bleeding pattern?

Perimenopause can feel unpredictable, yet clear information lets you spot risks, ignore myths, and set boundaries that fit your life, whether you are open to pregnancy or keen to avoid it.