Pregnancy and contraception in perimenopause

Yes. Pregnancy is still possible in perimenopause for as long as you are ovulating, even when your periods are irregular or months apart.¹,² Guidance on how long to keep using contraception differs a little by source. The Menopause Society advises it until menopause is confirmed, which is one year after your final period.² UK guidance from the Faculty of Sexual and Reproductive Healthcare (FSRH) is age-based: stop after one year without a period if you are over 50, or two years if you are 40 to 49, and in general most women can stop at 55.⁵,⁶ Which of these applies to you is a question for your doctor.

A skipped period feels like a sign that fertility is winding down. In perimenopause, it often is not.

Can you still get pregnant in perimenopause?

Perimenopause is defined by irregular cycles, and irregular is not the same as over. Your estrogen and progesterone levels swing, and ovulation becomes less consistent rather than stopping all at once.¹ You can go months without a period and then ovulate unexpectedly. Menopause is only confirmed after 12 consecutive months without a period, so until then ovulation, and therefore pregnancy, remains possible.²

Fertility does fall. Johns Hopkins Medicine says both the number and the quality of eggs decrease with age, that fertility begins declining in the early 30s and speeds up after about 37, and that by 40 the chance of conceiving in a single cycle is less than 10%.³ Cleveland Clinic gives about 10% per cycle at 40, compared with about 25% in the early 30s.⁴ By 45, pregnancy is highly unlikely but still possible until menopause.³ The risk of early pregnancy loss also rises with age, and about half of early losses involve chromosomal abnormalities.³

A lower chance each month is not a zero chance. That gap is where unplanned pregnancies happen.

How long do you need contraception in perimenopause?

The sources agree on the principle: if you do not want to become pregnant, keep using contraception until your doctor confirms it is safe to stop.¹,¹⁰ They differ on the exact timing:

• The Menopause Society: until menopause is confirmed, one year after your final menstrual period.²

• The NHS and FSRH: one year after your last period if you are 50 or over, two years if you are 40 to 49.⁵,⁶

• The FSRH also says that in general all women can stop contraception at 55, when natural loss of fertility can be assumed for most women.⁵

The waiting period is long because a gap in your periods is not proof that ovulation has ended. Hormones that rise and fall unpredictably can produce a long gap and then an ovulation.¹

Two things can make the timing harder to read. Hormonal contraception can make it harder to tell whether you have reached perimenopause or menopause,⁶ and NICE says a blood test for follicle-stimulating hormone (FSH) should not be used to diagnose menopause in women using combined hormonal contraception.⁸ Harvard Health notes that only 12 months without a period while off hormones is wholly reliable.⁹ If you use hormonal contraception, your doctor can talk you through how to work out when stopping is appropriate.

Hormone therapy is not a substitute. NICE states that HRT is not a contraceptive,⁸ and the NHS says the same.⁷ Emergency contraception can be used at any age.⁷

What contraception options do authoritative sources describe for perimenopause?

Methods fall into hormonal and non-hormonal groups. What follows is what the sources say about each, not advice on which to choose. That choice depends on your health history, and it belongs with your doctor.

• Combined methods (estrogen plus progestin: pill, patch, ring). The FSRH says use may continue between ages 40 and 50, then stop at 50 and switch to a non-hormonal method or a progestogen-only one.⁵ The NHS says the combined pill is not recommended from age 50 because the risks generally outweigh the benefits.⁶ Harvard Health describes low-dose pills as a good choice for irregular bleeding in women who need birth control and do not smoke, because they also suppress ovulation.⁹

• Progestogen-only methods (pill, implant, hormonal IUD). The FSRH says these may continue beyond 50, up to 55.⁵ A hormonal IUD can stay in place until menopause, and the strongest types, if fitted after 45, can last until 55.⁷ Hormonal IUDs often lead to lighter periods, or stop them altogether.

• Progestogen injection. The FSRH says use may continue between 40 and 50, and that women over 50 should be counseled about switching to another method.⁵

• Copper IUD. It contains no hormones. If fitted after age 40, it can stay in place until 55.⁷ It can cause heavier or more painful periods, especially in the first few months, which matters if perimenopause has already made your bleeding heavy.

• Barrier methods and permanent contraception. Condoms and diaphragms contain no hormones, though on their own they are generally less effective at preventing pregnancy than long-acting methods. Tubal ligation or a partner's vasectomy are permanent options.

Some of these methods also change bleeding patterns, which can be relevant when perimenopause has made your periods heavy or unpredictable. Our guide to your periods in perimenopause covers what is typical. If you are also weighing hormone therapy, see HRT and hormone testing in perimenopause.

Can tracking your cycle tell you when you are safe?

No. In Moody data, average cycle length shortens with age, and month-to-month variability widens again in the mid-forties. You can read more in your cycle gets shorter as you age, not longer. A cycle that no longer follows a pattern is a cycle you cannot use to predict ovulation.

Moody Month is not a form of contraception, and it cannot tell you whether you are ovulating or whether you could become pregnant. What tracking can do is show you your own pattern of bleeding and symptoms, so you arrive at a doctor's appointment with clearer information.

What if you hope to become pregnant?

Everything above is about preventing pregnancy. If you hope to become pregnant in your forties, the right person to talk to is a doctor or fertility specialist, who can look at your age and your history. A general guide cannot tell you what is likely for you.

When to see a doctor

Mayo Clinic lists these reasons to contact a healthcare professional: bleeding that is very heavy, bleeding that lasts longer than seven days, bleeding between periods, or periods that are usually less than 21 days apart.¹ Cleveland Clinic adds soaking a pad or tampon every one to two hours, large clots, and bleeding after sex.¹⁰ If you have gone 12 months without a period and then bleed, tell your healthcare provider, because it can signal a health issue.¹,⁶ A missed period in your forties can be perimenopause, but it can also be pregnancy, and a doctor can help you tell which.

Read next: Your periods in perimenopause: what changes and when it ends, HRT and hormone testing in perimenopause