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Can You Get Pregnant With One Ovary?

Yes — many people conceive naturally with one ovary. Fertility depends more on egg quality, hormone balance, and overall reproductive health than the number of ovaries alone. Whether you were born with one, had surgery, or lost one due to a medical condition, it’s still possible to become pregnant.

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Author

Tassia O’Callaghan

Reviewed by

Kayleigh Hartigan

10 min read

Published 25 October 2025

Spotlight:

  • If your remaining ovary and fallopian tube are healthy, your chances of conceiving are very similar to someone with two ovaries.

  • The remaining ovary often becomes slightly larger and ovulates every month, a process known as compensatory hypertrophy.

  • Menopause may come a little earlier — around one to two years on average — but most people still experience it in their late 40s or early 50s.

  • Fertility treatments like IVF, IUI, and egg freezing remain effective, though you may produce fewer eggs per cycle.

  • One ovary may be removed due to ovarian cysts, endometriosis, or a higher cancer risk, while some people are born with just one.

  • The remaining ovary continues to produce oestrogen and progesterone, helping maintain regular cycles and hormonal balance.

What is an ovary and why does it matter for fertility?

Ovaries are small, almond-shaped reproductive organs that produce eggs and hormones like oestrogen and progesterone. Most people with ovaries have two — one on each side of the uterus — but it’s possible to live and conceive with just one. [1]

Every menstrual cycle, one ovary typically releases a mature egg (ovulation). With one ovary, your body can still continue this process monthly, meaning ovulation — and therefore pregnancy — can still occur. [2]

Why would someone have one ovary?

There are several reasons why someone might have one ovary, either from birth or following medical intervention:

  • Surgical removal (oophorectomy or salpingo-oophorectomy): The most common cause. Surgery might be done to treat conditions such as ovarian cysts, endometriosis, ovarian torsion, or ovarian cancer. [3,4,5]

  • Endometriosis: When tissue similar to the lining of the womb grows outside it, it can cause severe pelvic pain and damage to one ovary. In some cases, surgery to remove the affected ovary may be recommended to relieve pain or prevent further complications. [6,7]

  • Injury or infection: Severe pelvic infections or trauma can sometimes damage an ovary. [6]

  • Inherited cancer risk: People with BRCA1 or BRCA2 gene mutations, or a strong family history of ovarian cancer, may choose to have their ovaries removed as a preventive measure. [6,8]

  • Congenital absence: Rarely, someone is born with only one ovary due to developmental differences (AKA unilateral ovarian agenesis). [9]

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How is having one ovary diagnosed?

If you’ve had surgery to remove an ovary, your doctor will have already confirmed this through medical records or imaging. But for some, the discovery of having one ovary happens unexpectedly — often during a fertility scan, ultrasound, or laparoscopy for another reason.

For those born with one ovary, it’s not always something that’s picked up early. Because the body usually develops and functions normally with one ovary, it’s common for the difference to go unnoticed until reproductive imaging is done later in life. This might happen during:

  • Routine pelvic ultrasound: Often done for fertility checks, period changes, or pelvic pain. [10]

  • MRI or CT scans: Sometimes used to investigate reproductive anatomy in more detail. [11,12]

  • Laparoscopy: A keyhole procedure where the reproductive organs are viewed directly. [13]

If you’re unsure whether you have one or two ovaries, a transvaginal ultrasound is usually the first step. It’s a simple, non-invasive scan that provides a clear picture of your uterus and ovaries.

For those who’ve had an oophorectomy, your healthcare team should explain what was removed — one ovary (unilateral oophorectomy) or both (bilateral oophorectomy). If your surgery took place years ago, your GP or gynaecologist can access hospital records to confirm.

Can having one ovary affect fertility?

Having one ovary can slightly reduce your overall ovarian reserve — the number of eggs available in your lifetime — but it doesn’t necessarily mean you’ll struggle to conceive. What’s remarkable is how efficiently the body adapts. [14]

When one ovary is removed (a unilateral oophorectomy), the remaining ovary often undergoes what’s known as compensatory hypertrophy. In simple terms, it steps up its function. Studies have shown that the remaining ovary can increase in size and become more responsive to hormonal signals from the brain, helping to maintain ovulation and hormone balance each cycle — although these studies were carried out on children and teenagers who had surgery to remove an ovary. [15]

That said, research might suggest some measurable biological differences. Immediately after surgery, ovarian reserve markers like Anti-Müllerian Hormone (AMH) often drop. A small prospective study found that AMH levels decreased across all age groups three months after surgery but recovered within a year in younger and early reproductive-age patients. However, recovery was slower — or incomplete — in those closer to their late 30s. [16]

But fertility outcomes will still depend on:

  • Your age: Egg quality naturally declines with age, especially after 35. [17]

  • The health of your remaining ovary and fallopian tube.

  • Any underlying conditions: For example, endometriosis or prior pelvic surgery may affect conception chances. [18]

What are the chances of getting pregnant with one ovary?

If your remaining ovary and fallopian tube are healthy, your chances of conceiving are close to those with two ovaries.

Although there isn’t enough large-scale research carried out on natural pregnancy rates with one ovary, one study from New York University found a 45.8% live birth rate per embryo transfer in people with one ovary — close to the 46.6% rate in those with two. Another review of 19,000 IVF cycles found no significant difference in pregnancy success between people with one ovary and those with both. [19,20]

But it’s worth noting that these studies only reviewed ART (assisted reproductive technology) cycles, not natural cycles.

Will I go into early menopause with one ovary?

Not necessarily — but menopause may come a little sooner.

Large population studies show that having a unilateral oophorectomy tends to bring menopause forward by around one to two years on average. For example, a Norwegian study of more than 23,000 women found that menopause occurred at 49.6 years in those with one ovary compared to 50.7 years in those with two. A Danish cohort reported almost identical findings — a 1.8-year difference on average. [21,22]

The effect is more noticeable if surgery happens before age 40. A Canadian study found that women who had an ovary removed in their 20s–30s were about twice as likely to reach menopause early (before 45) and four times as likely to experience premature ovarian insufficiency (before 40). [23]

So while menopause may arrive slightly earlier, most people with one ovary still experience it at a normal age — typically in their late 40s or early 50s.

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Does having one ovary affect fertility treatment?

Having one ovary doesn’t mean you can’t have successful fertility treatment — but it can slightly change how your body responds to medication. Here’s what the research says for the most common treatment types.

IVF (in vitro fertilisation)

During IVF, having one ovary may slightly change how your body responds to stimulation, but it doesn’t appear to reduce your overall chance of success. Research shows that while people with one ovary often produce fewer eggs, their embryo quality and live birth rates are on par with those who have two. In other words, the remaining ovary usually compensates — it may just need a bit more support, such as higher medication doses or an extra day of stimulation. [19,20]

Clinics will adjust your IVF protocol accordingly, focusing on maximising egg quality rather than quantity. So even with a lower ovarian reserve, the likelihood of achieving a healthy pregnancy through IVF remains reassuringly high.

IUI (intrauterine insemination)

If your remaining ovary and fallopian tube are healthy, IUI can still be a good option. Each month, your body typically alternates which ovary releases an egg — but when one has been removed, the remaining ovary often adapts through what’s known as compensatory hypertrophy. That means it can ovulate almost every cycle on its own, keeping your chances of conception steady. [15]

Your clinic will time insemination based on ovulation from that ovary, usually confirmed through scans or ovulation tracking. As long as the fallopian tube on that side is open and sperm quality is good, IUI success rates are comparable to those seen in people with two ovaries. [24]

Egg freezing

If you’re freezing your eggs with one ovary, you can still expect good results — but you may retrieve fewer eggs per cycle, since egg collection normally takes place from both ovaries. The remaining ovary often compensates by producing more follicles than expected (thanks again to compensatory hypertrophy), but overall yield may still be lower. [15]

Your doctor may recommend slightly higher medication doses or more than one stimulation cycle to reach your desired egg count. Even so, the egg quality and fertilisation potential are typically just as strong as in those with two ovaries.

How to conceive with one ovary

If your remaining ovary and fallopian tube are healthy, your chances of conceiving naturally are usually similar to someone with two ovaries. The body often compensates for the missing ovary, so ovulation still happens regularly — typically every month, rather than every other.

When trying to conceive, the same general advice applies as it does for anyone else: [25]

  • Track ovulation: Use ovulation predictor kits (OPKs), a fertility app, or basal body temperature tracking to pinpoint your fertile window. Regular tracking helps you understand your cycle and time sex for your most fertile days.

  • Have regular, well-timed sex: Aim for sex every 2–3 days throughout your cycle, or daily during your fertile window, to increase your chances of sperm meeting the egg when ovulation happens.

  • Support your overall health: Eat a balanced diet, move regularly, and try to maintain a healthy BMI. These small, steady habits can help support hormone balance and regular ovulation.

  • Take a prenatal supplement: Start a daily folic acid or prenatal vitamin (ideally before conception) to support early pregnancy development and reproductive health.

  • Manage stress and rest: Fertility can be affected by stress, poor sleep, and burnout — so make time for recovery, mindfulness, or anything that helps you unwind.

If you’ve been trying for 12 months with no success (or 6 months if you’re over 35), it’s a good idea to speak to your GP or a fertility specialist — and make sure to mention that you have one ovary. They may recommend:

  • A HyCoSy test to check that the fallopian tube on your remaining side is open and healthy.

  • Hormone testing (like AMH or FSH) to assess your ovarian reserve.

Otherwise, your approach to TTC doesn’t need to change — most people with one ovary can conceive naturally without additional medical intervention.

Getting pregnant with one ovary FAQs

Can ovaries grow back after being removed?

No — once an ovary has been surgically removed, it can’t grow back. In most cases, this allows your menstrual cycles and fertility to continue as normal. If you’ve had one ovary removed and are trying to conceive, your remaining ovary can still release eggs and support a healthy pregnancy.

What happens to your hormones when you have one ovary removed?

When one ovary is removed, the remaining ovary usually takes over hormone production — so most people continue to have regular cycles and balanced levels of oestrogen and progesterone. You might notice temporary hormonal changes, like mild hot flashes or irregular periods, while your body adjusts. Over time, your hormone levels typically stabilise, and you’ll still go through menopause naturally — though it may happen slightly earlier than average. In short, one healthy ovary is usually enough to maintain normal hormonal function and fertility. [26]

Can you have twins with one ovary?

Yes — it’s still possible to have twins with one ovary. Ovulation usually happens from one ovary each month, but sometimes that ovary can release more than one egg, leading to non-identical (fraternal) twins if both are fertilised. The chance of identical twins (when one fertilised egg splits in two) stays the same as for anyone else — about 1 in 250 pregnancies. So even with one ovary, twin pregnancies can still happen naturally, especially if you’re over 35 or have a family history of fraternal twins. [27,28]

Sources

  1. Gibson E, Mahdy H. Anatomy, Abdomen and Pelvis, Ovary. Updated 2023 Jul 24.
  2. NHS. Periods and fertility in the menstrual cycle. Page last reviewed: 05 January 2023.
  3. Al-Turki HA. Fertility after oophorectomy due to torsion. Saudi Med J. 2015 Mar;36(3):368-70. doi: 10.15537/smj.2015.3.10396. PMID: 25737184; PMCID: PMC4381026.
  4. NHS Sandwell and West Birmingham, NHS Trust. Laparoscopic/Open Unilateral or Bilateral Salpingo-oophorectomy (BSO/USO). Issue Date: February 2023.
  5. NHS Bradford Teaching Hospitals, NHS Foundation Trust. Laparoscopic oophorectomy.
  6. NHS Royal Berkshire, NHS Foundation Trust. Having a laparoscopic salpingo-oopherectomy (removal of one or both fallopian tubes and one or both ovaries). Reviewed: March 2023.
  7. NHS. Endometriosis. Page last reviewed: 27 August 2024.
  8. Yi H, Zhang N, Sundquist J, Sundquist K, Zheng X, Ji J. Long-term outcomes after unilateral salpingo-oophorectomy: A registry-based retrospective cohort study. PLoS Med. 2025 Jul 7;22(7):e1004639. doi: 10.1371/journal.pmed.1004639. PMID: 40622947; PMCID: PMC12233271.
  9. Chen, H.A., Grimshaw, A.A., Taylor-Giorlando, M. et al. Ovarian absence: a systematic literature review and case series report. J Ovarian Res 16, 13 (2023). https://doi.org/10.1186/s13048-022-01090-1.
  10. NHS. Ultrasound scan. Page last reviewed: 25 February 2025.
  11. NHS. MRI scan. Page last reviewed: 11 September 2025.
  12. NHS. CT scan. Page last reviewed: 08 November 2023.
  13. NHS. Laparoscopy (keyhole surgery). Page last reviewed: 20 December 2023.
  14. NHS Wirral University Teaching Hospital, NHS Foundation Trust. Laparoscopic Oophorectomy.
  15. Mayhew AC, Bost J, Linam L, Milla S, Farahzad M, Childress KJ. Compensatory Ovarian Hypertrophy after Unilateral Oophorectomy: Evaluation of Ovarian Volumes in Pediatric and Adolescent Populations. J Pediatr Adolesc Gynecol. 2020 Dec;33(6):631-638. doi: 10.1016/j.jpag.2020.07.001. Epub 2020 Jul 18. PMID: 32688053; PMCID: PMC7725918.
  16. Dzotsenidze S, Pkhaladze L, Kristesashvili J, Davidovi N, Hammoude S, Zurmukhtashvili M. FUNCTIONAL STATE OF THE REPRODUCTIVE SYSTEM AFTER UNILATERAL OOPHORECTOMY. Georgian Med News. 2024 Jun;(351):170-174. PMID: 39230242.
  17. NHS The Leeds Teaching Hospitals, NHS Trust. Fertility preservation information for women wanting to keep their childbearing options open. Page last reviewed: 03/10/2025.
  18. NHS. Infertility. Page last reviewed: 09 August 2023.
  19. Auran E, Cascante S, Blakemore J. Two is not always greater than one: patients with one ovary have similar assisted reproductive technology (ART) outcomes compared to patients with two ovaries. J Assist Reprod Genet. 2022 Aug;39(8):1789-1796. doi: 10.1007/s10815-022-02534-9. Epub 2022 Jun 18. PMID: 35716337; PMCID: PMC9428067.
  20. Younis JS, Naoum I, Salem N, Perlitz Y, Izhaki I. The impact of unilateral oophorectomy on ovarian reserve in assisted reproduction: a systematic review and meta-analysis. BJOG. 2018 Jan;125(1):26-35. doi: 10.1111/1471-0528.14913. Epub 2017 Oct 3. PMID: 28872775.
  21. Bjelland, E.K., Wilkosz, P., Tanbo, T.G. and Eskild, A., 2014. Is unilateral oophorectomy associated with age at menopause? A population study (the HUNT2 Survey). Human reproduction, 29(4), pp.835-841.
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