Can You Get Pregnant During Perimenopause? Odds, Contraception and HRT

Yes, you can. Fertility in your forties is low, unpredictable and not zero, and the gap between how unlikely pregnancy feels and how possible it remains is exactly where unplanned pregnancy at this age comes from.

The short answer: the UK's Faculty of Sexual and Reproductive Healthcare puts the chance of pregnancy over a year of unprotected sex at "around 10–20% for women aged 40–44 and closer to 12% for women 45–49" (FSRH, August 2017, amended May 2025). HRT is not contraception — the NHS says so in those words (NHS). And how long you keep using contraception depends on which country's guidance you are reading: the NHS says two years after your final period if you are 40 to 49 and one year if you are 50 or over, while the US Office on Women's Health gives one flat year at any age.

How likely pregnancy is in your 40s and early 50s

The FSRH is the only body among the sources used here that publishes a yearly figure by age band. Drawing on a set of reviews, it states: "the chance of pregnancy for a woman having unprotected sexual intercourse (UPSI) over the course of a year is around 10–20% for women aged 40–44 and closer to 12% for women 45–49."

That sentence repays a second reading, because 12% sits inside the 10–20% range: the figure for the older band is not plainly lower than the figure for the younger one. The guideline does not explain the overlap, and I cannot resolve it from the document, so it is quoted here as written rather than tidied up. What it does say unambiguously is the next sentence: "Spontaneous pregnancy is rare in women over 50."

A second figure circulates widely and is not the same measurement. ACOG tells patients that "for healthy couples in their 20s and early 30s, around 1 in 4 women will get pregnant in any single menstrual cycle. By age 40, around 1 in 10 will get pregnant per menstrual cycle" (ACOG). One in ten per cycle and 10–20% per year cannot both describe the same population: a 1-in-10 chance repeated over twelve cycles compounds to about 72% (1 − 0.9¹², my arithmetic, not a figure either source publishes), which is nowhere near 10–20%. ACOG's number describes healthy couples trying to conceive; the FSRH's describes women having unprotected sex across a year. Neither source cross-references the other, so this page states both and does not blend them.

Where they agree is at the top of the range. ACOG: "By 45, fertility has declined so much that getting pregnant naturally is unlikely." FSRH: spontaneous conception after 55 is "exceptionally rare even in women still experiencing menstrual bleeding."

Unlikely is not the same as impossible, and UK population data shows what that difference looks like in practice. The FSRH notes that live births to women over 40 in England and Wales nearly doubled between 2000 and 2015, from 15,066 to 29,241, and that in 2015, 28.1% of recorded pregnancies in women aged 40 and over in England and Wales ended in therapeutic abortion — one of the highest abortion-to-live-birth ratios of any age group.

If a pregnancy in this window would be wanted rather than unexpected, the conversation changes but does not get simpler. ACOG advises that anyone older than 40 should have a fertility evaluation before trying to conceive, rather than after six or twelve months of trying. It also sets out why later pregnancy is managed differently: higher rates of miscarriage and stillbirth above 35, increased risk of pre-eclampsia above 40, and a rising chance of chromosomal conditions — ACOG gives the risk of a pregnancy affected by Down syndrome as 1 in 294 at age 35 and 1 in 86 at age 40. The FSRH adds that miscarriage rates rise above 50% for women over 45, and that women over 40 are nearly three times as likely to have an ectopic pregnancy, although in the UK only about 1.1% of pregnancies are ectopic, so the absolute risk stays low. These are reasons to involve a clinician early, not reasons to decide anything from a web page.

Why skipped periods don't mean you can't conceive

The mechanism is simple and it is the part most pages skip. Ovulation happens first; the period follows roughly two weeks later. ACOG describes a normal cycle that way — "Ovulation occurs in the middle of the cycle. If a woman does not get pregnant, a period starts about 2 weeks later" — and then describes what changes in perimenopause: "Some months, the ovaries may release an egg. Other months, they do not release an egg" (ACOG FAQ162).

Put those two sentences together and the practical conclusion follows. A gap in your calendar is a record of what your ovaries did not do last month. It carries no information about next month, and if an egg is released during a long gap, conception can happen before any bleed arrives to announce that your cycles had resumed.

The Office on Women's Health states the same thing without hedging: "You can still get pregnant during perimenopause, the transition to menopause, even if you miss your period for a month or a few months", because "you may still ovulate, or release an egg, on some months. But it is impossible to know for sure when you will ovulate" (OWH).

One detail runs against intuition. Ageing ovaries are not only less likely to release an egg in a given month — they are also more likely to release more than one when they do. ACOG notes that "multiple pregnancy is more common when you are older. As the ovaries age, they are more likely to release more than one egg each month."

One safety point belongs here even though it is about bleeding rather than fertility. Any vaginal bleeding more than twelve months after your last period needs checking, including a single episode of spotting (NHS). For how ordinary perimenopausal bleeding usually behaves and where the line sits, see how cycles change through the transition, and when a change needs a clinician.

How long to keep using contraception

This is the question the page exists to answer, and the honest version starts with an admission the FSRH makes itself: "there is very little scientific evidence to inform guidance as to how and when methods of contraception can be discontinued". What follows is therefore expert judgement, and the UK and the US have reached different judgements.

Why the two differ. Both start from the same problem — menopause can only be confirmed looking backwards, after twelve months without bleeding — and solve it differently. The UK adds a margin for younger women, on the reasoning that a 45-year-old who has stopped bleeding is less likely to be genuinely post-menopausal than a 52-year-old is, and then caps the whole question with an age at which the margin stops mattering. The US guidance quoted here states one rule for everyone and leaves method-specific timing to clinical guidance such as ACOG's.

Neither is "right". If you are following UK care, the two-year rule under 50 is the safer figure of the two and is what your GP will use. If you are in the US, the one-year rule is what the Office on Women's Health publishes, and ACOG's 50–55 window is what applies to a coil or implant already in place. Where the two systems converge is at the top: 55 in the UK, 50–55 in ACOG's bulletin.

If the exact definition of "your last period" is the sticking point, what perimenopause is and the twelve-month rule that ends it sets out the definition these rules are built on.

If your periods are hidden by contraception

For a large number of women the rules above are unusable as written, because the method itself has removed the signal they depend on. The NHS lists which ones do it: the progestogen-only pill, the IUS (hormonal coil), the implant and the injection "can make periods irregular or stop completely", while "the combined pill causes monthly bleeds like a period for as long as you take it."

The obvious workaround — a blood test — is specifically ruled out. The FSRH states that during perimenopause "isolated serum estradiol, FSH and LH levels can be misleading and should not be used as a basis for providing advice about stopping contraception; ovulation may still occur with risk of pregnancy". NICE puts a narrower version of the same instruction in its menopause guideline: "Do not use a follicle-stimulating hormone (FSH) blood test to identify menopause in people using combined oestrogen and progestogen contraception or high-dose progestogen" (NICE NG23, 1.3.5).

The FSRH allows one narrow exception, and it is worth knowing precisely because it is so narrow. It restricts FSH measurement for this purpose to women over 50, using progestogen-only contraception, who have no periods. Even then the result does not end the matter: if FSH is above 30 IU/L the method can be stopped after one more year; if it is in the premenopausal range, the method continues and FSH is rechecked a year later. The guideline's own caution on what that number means is blunt — an FSH above 30 IU/L "indicates a degree of ovarian insufficiency, but not necessarily sterility."

Two method-specific details sit inside that exception. Women using combined hormonal contraception have "very suppressed levels of estradiol, FSH and LH even if measured during the HFI" — the hormone-free interval — so the test cannot inform anything. And for the injection, the FSRH notes that DMPA can suppress FSH to some extent — a woman on it "could be menopausal yet show no increase in FSH levels" — so the best time to measure is just before the next injection is due.

What an FSH test can and cannot settle, and at what age covers the testing question in full, including why NICE advises against testing at all for most women over 45.

HRT is not contraception, and the coil that can do both jobs

Four bodies state this independently, which is unusual enough to be worth listing. The NHS: "HRT is not contraception" (NHS). The FSRH: "As HRT is not a contraceptive method, effective contraception should be maintained in conjunction with sequential HRT if women are still perimenopausal or their menopausal status is uncertain." NICE, in its premature ovarian insufficiency recommendations, lists "that HRT is not a contraceptive" among the things to explain to patients (NICE NG23, 1.7.7). And ESHRE's 2024 POI guideline recommends that clinicians "advise women with POI that Hormone Replacement Therapy (HRT) does not provide contraception, in order to assist them with their family planning" (ESHRE, 2024).

The evidence behind the warning is thinner than the warning is loud, and the FSRH says so. It cites a small study of sequential HRT users aged 42 to 52 in which HRT "inhibited ovulation in only 40% of women with regular cycles", adding that "some women who had been anovulatory or had irregular cycles prior to HRT did subsequently ovulate on HRT." That second clause is the one that matters most: starting HRT can coincide with ovulation resuming in women whose cycles had stopped being reliable.

Two consequences follow for anyone with POI or early menopause specifically. ESHRE's guideline notes that natural conception occurs in up to 15% of women with non-surgical POI who have intermittent ovarian function, "although probably in <5% overall", and recommends contraception for anyone with non-surgical POI who wishes to avoid pregnancy. The Menopause Society gives a figure in the same range — "spontaneous pregnancy may occur in about 5% of women with POI" — and notes that combined oral contraceptives may serve as an alternative form of hormone therapy for those women, because they do both jobs at once (The Menopause Society, 2022).

The coil is the method that can do both jobs — with two different clocks. The FSRH says women "may use a 52mg levonorgestrel intrauterine device (LNG-IUD) with estrogen for up to 5 years for endometrial protection as part of an HRT regimen", and that women using one for that purpose "must have the device changed every 5 years". Separately, a 52 mg LNG-IUD inserted at 45 or over can stay in place for contraception until 55 — but the FSRH attaches a condition that is easy to miss: that ten-year allowance applies "provided it is not being used as the progestogen component of hormone replacement therapy (HRT) for endometrial protection." A coil doing both jobs runs on the five-year clock, not the age-55 one.

Two caveats on that, both of which the guidelines state themselves:

• Licence versus guideline. All 52 mg LNG-IUDs are licensed for eight years for contraception and for four years for endometrial protection with HRT. The FSRH supports use for up to five years in that second role — a deliberate step beyond the licensed duration, which is the kind of thing worth knowing before a conversation about replacement timing.
• The UK and US positions are not the same. The Menopause Society's 2022 position statement calls this an "off-label use of a levonorgestrel-containing intrauterine device to prevent endometrial hyperplasia", notes it "can protect against unwanted pregnancy in women initiating hormone therapy for symptom management before their final menstrual period", and adds: "There are limited clinical trial data to support this use." The UK recommends it; the US flags it as off-label with limited trial evidence. Both statements are current.

The methods that cannot take on the endometrial job are worth naming too, because the assumption that any progestogen will do is a common one. The FSRH states that the progestogen-only pill, the implant and the injection "are not licensed for and cannot be recommended as endometrial protection with estrogen-only HRT" — although all of them are safe to use as contraception alongside sequential HRT. And for women under 50 who need both symptom relief and contraception, the FSRH notes that combined hormonal contraception "can be used in eligible women aged under 50 as an alternative to HRT", which is also why the NHS flags 50 as the age to switch away from it.

For what the hormone therapy options themselves involve, the treatment options used during perimenopause and how the evidence stacks up covers them in detail.

Is it perimenopause, or am I pregnant?

A symptom list will not settle this, and the overlap is the reason. Set the NHS's early-pregnancy signs beside the NHS's perimenopause symptoms and a large middle section appears.

Sources for both columns: NHS, signs and symptoms of pregnancy and NHS, menopause and perimenopause symptoms.

Only the last three rows discriminate at all, and none of them is reliable enough to decide anything on — a symptom can be absent from a list and still be present in a person. What settles it is a test. MedlinePlus states that when periods stop in someone who had been having them, "the most common cause of secondary amenorrhea is pregnancy", and that assessment begins with an exam that "must be done to check for pregnancy. A pregnancy test will be done" (MedlinePlus).

When to take it is the part that perimenopause complicates. The usual instruction — test from the first day of your missed period — assumes you know when the period was due. The NHS gives the alternative for when you do not: "do the test at least 21 days after you last had unprotected sex" (NHS). That is the version that fits an unpredictable cycle.

On reading the result, the NHS is specific about the asymmetry: "A positive test result is almost certainly correct. However, a negative test result is less reliable." If you get a negative and still think you could be pregnant, retest after a few days, and speak to a GP if a second test is negative and your period still has not arrived.

When to get help: the NHS asks you to contact your GP or call NHS 111 if you have a combination of tummy pain low down on one side, vaginal bleeding or brown watery discharge, or pain at the tip of your shoulder and you might be pregnant — "even if you haven't had a positive pregnancy test". These can be signs of an ectopic pregnancy. The NHS says to call 999 or go to A&E immediately for a combination of sharp, sudden, intense tummy pain, feeling very dizzy or fainting, feeling sick and looking very pale (NHS).

Medicines to know about if pregnancy is possible

Pregnancy status changes what can be prescribed for perimenopausal symptoms, and the labels are not consistent with each other — which is worth knowing before assuming that one non-hormonal option behaves like another.

Elinzanetant (Lynkuet). The US prescribing information is unambiguous: the drug "is contraindicated in pregnancy", because exposure "may cause pregnancy loss or stillbirth when administered during pregnancy". Before starting it, prescribers are told to "exclude pregnancy in females of reproductive potential". The patient counselling section goes further still: it advises women who could become pregnant "to use effective contraception during treatment with LYNKUET and for two weeks after discontinuing treatment", and to stop the drug if pregnancy is confirmed (openFDA label, SPL effective 16 June 2026).

Fezolinetant (Veozah). The same class of drug, for the same symptom, with different requirements. Its US label contraindicates cirrhosis, severe renal impairment and concomitant CYP1A2 inhibitors — not pregnancy. The words "exclude pregnancy", "pregnancy test" and "contraception" do not appear anywhere in it; its pregnancy section records only that there are no human data and summarises animal findings (openFDA label, SPL effective 26 February 2026). Two drugs that treat the same thing can therefore carry very different instructions about pregnancy.

Estrogen-containing hormone therapy. Here the US labels disagree with each other, and I am reporting that rather than picking one. A generic oral estradiol label lists "Known or suspected pregnancy" among its contraindications, adding "There is no indication for estradiol tablets in pregnancy." The current Premarin label does not list pregnancy among its contraindications at all; its pregnancy section says "PREMARIN is not indicated for use during pregnancy" and reports that "epidemiologic studies and meta-analyses have not found an increased risk of genital or nongenital birth defects … following exposure to combined hormonal contraceptives (estrogen and progestins) before conception or during early pregnancy". The older generic label makes a similar reassurance in its own words. The practical reading: hormone therapy is not something to continue into a pregnancy, and the labels that address the question do not suggest that inadvertent early exposure causes birth defects. If you conceive while taking it, that is a same-week conversation with a clinician, not an emergency.

Every label quoted above is a US label, retrieved from the FDA's openFDA service. Product information in the UK and the EU is written by different regulators and I have not verified its wording here, so do not read this section as applying outside the US. Where you are in the transition, and what the late stage means is a better starting point than a drug label for working out whether any of this applies to you yet.

Common questions about pregnancy and contraception in perimenopause (FAQ)

Can you get pregnant on HRT? Yes. Standard menopausal hormone therapy is not a contraceptive. The NHS states it in four words — "HRT is not contraception" (NHS) — and the FSRH says effective contraception should be maintained alongside sequential HRT if you are still perimenopausal or your menopausal status is uncertain. The FSRH cites a small study of sequential HRT users aged 42 to 52 in which HRT "inhibited ovulation in only 40% of women with regular cycles", and in which some women who had been anovulatory or had irregular cycles before HRT went on to ovulate while taking it (FSRH).

Can you get pregnant without a period? Yes. Ovulation comes first and the period follows about two weeks later, so a long gap tells you what your ovaries did last month rather than what they will do next month. ACOG describes perimenopausal ovaries plainly: "Some months, the ovaries may release an egg. Other months, they do not release an egg" (ACOG FAQ162). The Office on Women's Health adds that you may still ovulate on some months but "it is impossible to know for sure when you will ovulate" (OWH).

When can I stop contraception? That depends on which country's guidance you are following, and the difference is real rather than a matter of phrasing. In the UK the NHS says you still need contraception for two years after your final period if you are aged 40 to 49, and for one year if you are 50 or over (NHS); the FSRH adds that in general everyone can stop at 55. In the US the Office on Women's Health gives one rule with no age split: continue until one full year after your last period (OWH). The FSRH is candid that "there is very little scientific evidence" behind any of these thresholds.

Can a blood test tell me I am no longer fertile? No. The FSRH is explicit that during perimenopause isolated serum estradiol, FSH and LH levels "can be misleading and should not be used as a basis for providing advice about stopping contraception", because ovulation may still occur. It adds that an FSH level above 30 IU/L "indicates a degree of ovarian insufficiency, but not necessarily sterility". The one narrow exception it allows is a single FSH measurement in a woman over 50 using progestogen-only contraception who has no periods — and even then the advice is to continue contraception for one more year (FSRH).

Can you get pregnant after menopause? Not naturally. The Office on Women's Health states that after menopause you will no longer be able to get pregnant (OWH). The difficulty is knowing when you have reached it: menopause is confirmed only after twelve consecutive months with no bleeding at all, including spotting, so the date is always established in hindsight. The FSRH puts the practical ceiling at 55, saying spontaneous conception after that age is exceptionally rare even in women still having some menstrual bleeding. Any vaginal bleeding more than twelve months after your last period needs checking, whatever your age (NHS).

Medical disclaimer: This article is for informational purposes only. Always consult a qualified healthcare provider before making changes to your health routine.

Sources

1. Faculty of Sexual & Reproductive Healthcare. FSRH Guideline: Contraception for Women Aged Over 40 Years — Clinical guideline. The cover page is dated "August 2017 (Amended May 2025)"; the metadata table on the same page reads "August 2017, Amended July 2023" and gives a publication date of October 2017. The cover date is quoted here. https://www.cosrh.org/Common/Uploaded%20files/documents/fsrh-guideline-contraception-for-women-aged-over-40-years.pdf
2. NHS. Menopause and perimenopause — Symptoms — Government health information, page last reviewed 19 May 2026. https://www.nhs.uk/conditions/menopause-and-perimenopause/symptoms/
3. NHS. Menopause and perimenopause — Things you can do — Government health information, page last reviewed 19 May 2026. https://www.nhs.uk/conditions/menopause-and-perimenopause/things-you-can-do/
4. NHS. Doing a pregnancy test — Government health information, page last reviewed 9 February 2022. https://www.nhs.uk/pregnancy/trying-for-a-baby/doing-a-pregnancy-test/
5. NHS. Signs and symptoms of pregnancy — Government health information, page last reviewed 31 July 2026. https://www.nhs.uk/pregnancy/trying-for-a-baby/signs-and-symptoms-of-pregnancy/
6. NHS. Ectopic pregnancy — Government health information, page last reviewed 23 August 2022. https://www.nhs.uk/conditions/ectopic-pregnancy/
7. Office on Women's Health, U.S. Department of Health and Human Services. Menopause basics — Government health information, last updated 2 April 2026. https://womenshealth.gov/menopause/menopause-basics
8. National Institute for Health and Care Excellence. Menopause: identification and management (NG23) — Clinical guideline; recommendations 1.2.3, 1.3.5 and 1.7.7 are cited here. https://www.nice.org.uk/guidance/ng23/chapter/Recommendations
9. American College of Obstetricians and Gynecologists. Having a Baby After Age 35: How Aging Affects Fertility and Pregnancy — Professional society patient FAQ, last updated February 2023, last reviewed April 2025. https://www.acog.org/womens-health/faqs/having-a-baby-after-age-35-how-aging-affects-fertility-and-pregnancy
10. American College of Obstetricians and Gynecologists. Perimenopausal Bleeding and Bleeding After Menopause (FAQ162) — Professional society patient FAQ, last updated October 2020, last reviewed February 2024. https://www.acog.org/womens-health/faqs/perimenopausal-bleeding-and-bleeding-after-menopause
11. American College of Obstetricians and Gynecologists. Long-Acting Reversible Contraception: Implants and Intrauterine Devices. Practice Bulletin No. 186 — Professional society practice bulletin, November 2017, reaffirmed 2024. https://www.acog.org/clinical/clinical-guidance/practice-bulletin/articles/2017/11/long-acting-reversible-contraception-implants-and-intrauterine-devices
12. The North American Menopause Society. The 2022 hormone therapy position statement of The North American Menopause Society — Professional society position statement. https://menopause.org/wp-content/uploads/professional/nams-2022-hormone-therapy-position-statement.pdf
13. European Society of Human Reproduction and Embryology. Guideline on the Management of Women with Premature Ovarian Insufficiency, 2024 — Professional society clinical guideline; recommendations 41, 42 and 103 are cited here. https://www.eshre.eu/-/media/sitecore-files/Guidelines/POI/2024/INTERNATIONAL-GUIDELINE-ON-POI_2024_2.pdf
14. MedlinePlus (U.S. National Library of Medicine). Absent menstrual periods — secondary — Government medical encyclopedia, review date 29 May 2026. https://medlineplus.gov/ency/article/001219.htm
15. U.S. Food and Drug Administration (via openFDA). LYNKUET (elinzanetant) capsules — prescribing information, SPL effective 16 June 2026. https://api.fda.gov/drug/label.json?search=openfda.brand_name:LYNKUET&limit=1
16. U.S. Food and Drug Administration (via openFDA). VEOZAH (fezolinetant) tablets — prescribing information, SPL effective 26 February 2026. https://api.fda.gov/drug/label.json?search=openfda.brand_name:VEOZAH&limit=1
17. U.S. Food and Drug Administration (via openFDA). PREMARIN (conjugated estrogens) tablets — prescribing information, SPL effective 4 June 2026; and estradiol tablets, SPL effective 22 January 2025. https://api.fda.gov/drug/label.json?search=openfda.brand_name:PREMARIN&limit=1

Claire Whitfield

Women's Health Specialist

A women's health specialist who reads the contraception guideline rather than the summary of it.

View profileView Xing profile