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What is perimenopause? Symptoms, age and how to know if you’re in it-image

What is perimenopause? Symptoms, age and how to know if you’re in it

Perimenopause is the time leading up to menopause, when your hormone levels start to change and your periods become less regular. It usually starts in your 40s and lasts several years, ending once you’ve gone 12 months without a period. During this time, many people notice symptoms such as hot flushes, sleep problems and mood changes. Perimenopause can creep up on you. Your periods might change, you might start waking at 3am, or you might feel more anxious than usual, without realising your hormones could be behind it. This guide explains what perimenopause is, when it starts, how long it lasts, how to tell if you’re in it and what can help. Quick facts: What is perimenopause? Perimenopause is the stage before menopause, when your ovaries gradually stop working as they used to. Your hormone levels start to change, your periods become less predictable, and you may notice new physical and emotional symptoms. What is the difference between perimenopause and menopause? Perimenopause, menopause and postmenopause are often used interchangeably, but they mean different things: Many people say “menopause” when they mean perimenopause. That’s understandable, but the difference matters. Perimenopause is usually when symptoms are most noticeable, and when you can still get pregnant. What age does perimenopause start? Perimenopause most often starts in your mid-40s, but everyone is different. Some people notice changes in their late 30s or early 40s, and others not until their late 40s. Menopause usually happens between 45 and 55. Under 45. If your periods stop before you’re 45, this is known as early menopause. Under 40. If your periods stop before you’re 40, it’s called premature menopause or premature ovarian insufficiency (POI). It affects around 1 in 100 women under 40. If you’re under 40 and your periods have become irregular or stopped, see your GP. POI needs proper assessment and treatment. Your genes, lifestyle habits like smoking, some medical treatments and surgery on your ovaries can all affect when perimenopause starts. Find out more in our guide to whether you can predict when menopause will happen. How long does perimenopause last? Perimenopause usually lasts several years, and the length varies a lot from person to person. For most, perimenopause will last about 4 to 8 years, but it can be longer (or shorter!). It ends once you’ve gone 12 months without a period. Symptoms don’t always stop when your periods do. Hot flushes and night sweats often carry on into postmenopause. In one large study, hot flushes and night sweats lasted more than seven years overall for around half of the women. What causes perimenopause? Perimenopause happens because your ovaries gradually run out of eggs and stop responding to the hormones that control your cycle. This is why symptoms can come and go, and why they can be so unpredictable. It’s also why a single blood test often can’t confirm perimenopause: your hormones can look normal one day and very different the next. What are the first signs of perimenopause? For many people, the first sign is a change to their periods. Your cycle might get shorter or longer, your periods might become heavier or lighter, or you might skip periods altogether. Other common early signs include: Period and cycle changes Often the earliest and most recognisable sign of perimenopause is a change in your menstrual cycle. This can include shorter cycles (less than 21 days), longer cycles or skipped periods, heavier or lighter periods than before, spotting between periods or more intense PMS symptoms. Hot flushes and night sweats Hot flushes are sudden feelings of heat, usually in your face, neck and chest, which can make your skin red and flushed. They can happen at any time, often with no obvious trigger. Falling oestrogen affects the part of your brain that controls body temperature, making it more sensitive to small changes. Night sweats are hot flushes that happen while you sleep. They can be heavy enough to soak your nightwear and bedding, and wake you up. Sleep disturbance Poor sleep is one of the most common and most underestimated symptoms. Night sweats can wake you, but falling progesterone and changing oestrogen levels can also affect your sleep directly. Many people find they wake in the early hours and can’t get back to sleep. Mood changes – anxiety, low mood and irritability Changing oestrogen levels can affect the brain chemicals involved in mood, such as serotonin. You might notice: These are some of the most often missed perimenopause symptoms, because they’re so easily put down to stress, relationship problems or a mental health condition. Brain fog and cognitive changes Many people notice difficulty concentrating, forgetfulness or a feeling of mental “fuzziness”, often called brain fog. Oestrogen plays a role in memory, attention and processing speed, so changing levels can affect how sharp you feel. Brain fog can be worrying, but it’s a common, recognised symptom of perimenopause, not a sign of something more serious. Vaginal and bladder changes Falling oestrogen can make the tissues of your vagina, vulva and urethra drier, thinner and less elastic. This is known as genitourinary syndrome of menopause (GSM), and it can cause vaginal dryness or discomfort, pain during sex, increased susceptibility to thrush or bacterial vaginosis, urinary urgency or frequency and recurrent urinary tract infections Low libido Changes in libido during perimenopause are driven by a combination of declining testosterone, vaginal discomfort, disrupted sleep and mood changes.  Skin, hair and body changes Decreased oestrogen reduces collagen production, causing skin to feel drier, thinner, and less elastic. Some people also notice increased sensitivity or new adult acne. Falling oestrogen alongside declining progesterone and testosterone changes the hair growth cycle, and many perimenopausal people notice hair thinning at the temples or crown. Hormone changes can affect where your body stores fat, with more weight gathering around your middle, even if your diet hasn’t changed. Joint pain and muscle aches Aching joints and muscles, especially stiffness in the morning, are a recognised symptom of perimenopause. Heart palpitations Some people notice […]

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Your Questions Answered | Fertility & Hormone Health FAQs-image

Your Questions Answered | Fertility & Hormone Health FAQs

Whether you’re trying to conceive, living with PMOS ( formerly known as PCOS), considering egg freezing, navigating perimenopause, or simply trying to understand what your hormones are doing, you are not alone. Reproductive health can feel confusing, especially when symptoms are dismissed, cycles become unpredictable, or you’re told to “just wait and see” without clear answers. But your questions deserve more than vague reassurance. They deserve clinical context, personalised support and practical next steps. Welcome to Your Questions Answered with Hertility,  our expert-led series answering the reproductive health, hormone and fertility questions you really want answered. I’m Zoya Ali, Hertility’s Senior Scientific Research Associate, and in this series I’ll be helping to break down complex fertility and hormone topics in a way that feels clear, clinically grounded and easy to understand. From irregular periods and PMOS to egg freezing, perimenopause and trying to conceive, my goal is to give you evidence-based information without shame, confusion or medical jargon. In this edition, we’re answering some of the most common questions we hear from the Hertility community, including what to do if you feel dismissed by your GP, whether egg freezing in your early thirties is worth it, why a PMOS diagnosis matters, and whether pregnancy is still possible during perimenopause. Have a question you’d like answered in a future edition of Your Questions Answered with Hertility? Submit your question here. Q: We’ve been trying to conceive for over a year. My GP told me to lose weight and said ovulation can happen at any time. I only get a period once every three months. I feel pushed aside. What can I do? First, I’m really sorry you’ve been made to feel like this, your concerns are completely valid. After 12 months of trying to conceive, you are entitled to a comprehensive fertility assessment. Being told to lose weight and come back later, with no investigations or plan is not adequate care and you deserve more than that. Now, let’s talk about what’s actually going on with your body, because irregular periods every three months are telling us something important. That pattern is known as oligomenorrhoea and it is a sign that your body may not be ovulating regularly. Ovulation is the event that makes conception possible, and if it’s only happening sporadically, or not at all, trying to conceive can become significantly harder. Weight can be one piece of this picture, and it’s worth being honest about that. Weight can affect how the body manages insulin and inflammation, both of which influence reproductive hormones and ovulation. But weight is one factor in a much larger story, and it should never be used as a reason to withhold investigations. The most common cause of irregular, infrequent periods is PMOS ( previously known as PCOS ) which is a hormonal and metabolic condition affecting how the ovaries function. But thyroid imbalance, raised prolactin, insulin resistance and stress can all produce a very similar picture. You cannot know which of these is driving your symptoms without testing. If you feel your GP is still not listening, you are entitled to ask for a referral to a gynaecologist or fertility specialist, or to seek a second opinion. At Hertility, our Advanced At-home Hormone and Fertility Test can give you clinical-grade results, insight into your egg count and screening for up to 18 reproductive health conditions, alongside a doctor-written report, personalised Care Plan and a Clinical Result Review Call. We also offer Fertility Nutrition Consultations that can support ovulation, hormone and metabolic health without shame, blame or crash dieting. You don’t have to wait to be taken seriously. Q: What is the success rate for egg freezing if you freeze your eggs in your early thirties? This is one of the most common questions I hear from people considering egg freezing, and I understand why, you want a number, something reassuring and concrete. The honest answer is that there isn’t one single success rate, let me explain why, and what the picture actually looks like. Age is genuinely one of the most important factors in egg freezing. Freezing in your late twenties to early thirties is the most recommended, because egg quality and quantity are typically the best. But age alone doesn’t determine your outcome, two women who are both 31 can have very different responses to fertility treatment depending on factors like their AMH levels and antral follicle count. When we talk about success rates, we’re really talking about a chain of events, and at each link in that chain, some eggs are naturally lost. First, your frozen eggs need to survive the thawing process, thaw survival rates are typically around 80 to 90%. Then, not every thawed egg will fertilise successfully. Not every fertilised egg will develop into a good-quality embryo. And not every embryo will implant and lead to a pregnancy. Sperm quality and uterine health both play a role at that final stage too. Most clinics recommend aiming for around 15 mature eggs to give yourself a reasonable chance of a future live birth, with some recommending closer to 20 if you’re hoping for more than one child. Depending on how your ovaries respond to stimulation, some people collect enough eggs in one cycle; others need two or more. This is why egg freezing planning really is personal, it’s not a one-size approach. An AMH blood test and pelvic ultrasound to check our Antral Follicle Count (AFC) are the best starting points for understanding your ovarian reserve. They can’t tell us about egg quality directly, that remains something we can only assess once eggs are fertilised, but they give us a meaningful picture of quantity and potential response to fertility medications. At Hertility, our Advanced At-home Hormone and Fertility Test includes insight into your egg count alongside a full hormone profile. We can also arrange a Pelvic Ultrasound Scan to assess your antral follicle count and pelvic structures, and we work with HFEA-accredited partner clinics to support a smooth referral process […]

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