News
Copper coil vs Mirena: Which is right for you?
Article produced in association with Spital Clinic
Both the copper coil and the Mirena are more than 99 per cent effective as contraceptives — but they work in completely different ways, have opposite effects on periods, and suit very different people.
With the FSRH’s May 2024 licence extension for the Mirena now in effect, this guide covers the five key differences using up-to-date UK evidence, not the older guidance that many sources still repeat.
How Each Device Works
The FSRH March 2023 guideline set out the terminology now used across UK clinical practice: the copper intrauterine device (Cu-IUD) and the levonorgestrel intrauterine system (LNG-IUD).
The copper coil works by releasing copper ions that are toxic to sperm, preventing fertilisation. It contains no hormones at all, making it a strong option for women who cannot or do not want hormonal contraception.
The Mirena — the most widely prescribed 52mg LNG-IUD in the UK — thickens cervical mucus to block sperm, thins the uterine lining, and may suppress ovulation, though most users continue to ovulate normally.
According to Hull University Teaching Hospitals NHS Trust, the hormone levels it produces are lower than those from the combined contraceptive pill — relevant for women advised to avoid higher-dose hormonal methods.
The hormone-free nature of the Cu-IUD is its defining advantage for some; the localised hormonal action of the LNG-IUD is its defining advantage for others.
According to NHS guidance on the copper coil, neither device interacts with medicines or herbal remedies, and both can be fitted in women who have never been pregnant.
The way each device works also determines what it does to periods — often the deciding factor.
Effectiveness and Duration
The NHS confirms both devices prevent pregnancy in more than 99 per cent of users. When it comes to contraceptive effectiveness, there is no meaningful difference between them.
Where they differ significantly is duration. The copper coil lasts up to 10 years, and one fitted in a woman aged 40 or over can remain in place until menopause under FSRH March 2023 guidance.
For the Mirena, the picture changed in May 2024: the FSRH CEU statement on extended LNG-IUD use confirmed that all 52mg LNG-IUDs — including the Mirena, Levosert, and Benilexa — are now licensed for eight years of contraceptive use, up from five under previous guidance.
When the Mirena is used as part of HRT, it protects the uterine lining for up to five years before requiring replacement. Smaller-dose devices such as Kyleena (20mcg) are licensed for five years, and Jaydess for three.
Both are long-acting reversible contraceptives — fertility returns immediately after removal, with no delay or washout period. Both are available without a GP referral through the coil insertion and removal service at Spital Clinic.
What Each Device Does to Periods
The most important practical difference is what each device does to periods — and they go in opposite directions.
The copper coil typically makes periods heavier, longer, and more painful; the NHS notes this may ease after a few months, but heavier bleeding is one of the most common reasons for early removal.
Both devices can cause irregular spotting in the first three to six months after fitting.
The Mirena does the opposite.
According to Hull University Teaching Hospitals NHS Trust, it reduces monthly blood loss by 86 per cent at three months and by 97 per cent at twelve months.
Nine in ten women who use it for heavy periods see a significant reduction; around 20 per cent have no bleeding at all; and 80 per cent report meaningful pain relief.
NHS information on the hormonal coil confirms that periods often become lighter, shorter, and less painful — with many users finding they stop entirely after the initial settling-in period.
For women whose choice of contraception is being shaped by troublesome periods, those statistics make the direction of the decision clear.
For women with already disrupted cycles, it is worth booking a private specialist assessment before deciding — for this group, the choice of coil is as much a treatment decision as a contraceptive one.
Unlike the copper coil, the Mirena is licensed as a first-line treatment for menorrhagia — heavy or prolonged bleeding defined as losing more than 80ml per cycle or periods lasting longer than seven days.
In around half of cases, heavy periods have no identifiable structural cause, making the Mirena’s targeted local action particularly useful: it reduces bleeding at the endometrial level without surgery, general anaesthesia, or high-dose systemic hormones, and offers a non-surgical alternative to procedures such as endometrial ablation.
Side Effects, Risks, and Who Cannot Use Each Device
Both devices carry the same procedural risks. Pelvic infection affects around 1 in 100 women in the first three weeks; expulsion happens in roughly 1 in 20; and uterine perforation occurs in approximately 2 in 1,000 fittings — slightly higher in women breastfeeding within six months of delivery. Ectopic pregnancy, though rare, is a risk if either device fails.
The side-effect profiles diverge beyond those shared risks.
The copper coil carries no hormonal side effects — heavier periods are its main downside. The
Mirena may cause acne, headaches, mood changes, breast tenderness, and ovarian cysts; most resolve without treatment, but they are worth considering for anyone sensitive to progestogen.
The Mirena is also unaffected by vomiting, diarrhoea, or most drug interactions.
Each device has its own contraindications. Neither should be fitted in the presence of an active sexually transmitted infection or unexplained uterine bleeding.
The Mirena is not suitable for women with a history of breast cancer, certain liver conditions, serious cardiovascular disease, or certain uterine abnormalities.
The copper coil, meanwhile, can be used as emergency contraception if fitted within five days of unprotected sex — the only intrauterine option for post-coital protection.
The Fitting Procedure and What to Expect
The fitting procedure is the same for both devices: a 10 to 15 minute clinical appointment, ideally towards the end of a period, though it can happen at any point in the cycle.
The full appointment takes around 30 minutes. Local anaesthetic gel or spray is used to manage discomfort, and the NHS advises taking ibuprofen or paracetamol about an hour beforehand.
No surgery or general anaesthetic is needed. Some cramping and light spotting in the days after fitting is normal and usually settles within a week. Neither device requires you to have had children previously.
Fertility returns immediately after removal of either device — there is no waiting period before trying to conceive.
For most women, the choice between the copper coil and the Mirena comes down to one question: are hormones acceptable or not?
The copper coil suits women who want hormone-free contraception, those who cannot use progestogen, and those who need emergency post-coital protection.
The Mirena suits women who want lighter or absent periods, those managing menorrhagia, and those using it as the progestogen component of HRT.
Both offer equivalent contraceptive effectiveness and full reversibility.
The FSRH’s May 2024 extension of the Mirena’s licence to eight years makes it a stronger long-term option than many comparisons suggest — worth knowing if the information you have found is based on older guidance.
This article is produced for informational purposes only and does not constitute medical advice, diagnosis or treatment. Clinical guidance referenced reflects published NHS and FSRH standards as at March 2025. Individual circumstances vary; readers are advised to consult a qualified healthcare professional before acting on any information in this article.
This piece was produced in association with Spital Clinic, which provided background clinical information for editorial purposes. Hyperlinks to external sources are included for reference only and do not represent an endorsement of any product, service or organisation.
Light exercise and less sitting may reduce pregnant women’s risk of serious blood pressure complications, according to a new study.
Researchers have proposed a daily activity and sleep guide that they say was linked to a nearly 30 per cent lower risk of hypertensive disorders of pregnancy.
The suggested pattern includes fewer than eight hours of sedentary time, at least seven hours of light physical activity, around 22 minutes of more intense activity and nearly nine hours of sleep.
The University of Iowa-led study examined the daily behaviours of 470 pregnant women across all stages of pregnancy.
Participants wore monitors that measured physical activity over 24-hour periods and recorded how long they spent asleep.
Hypertensive disorders of pregnancy include chronic high blood pressure, gestational hypertension and pre-eclampsia.
Gestational hypertension is high blood pressure that develops during pregnancy, while pre-eclampsia is a potentially serious condition involving high blood pressure and signs that organs may be affected.
Sedentary behaviour means being mostly inactive, such as sitting or lying down.
Light physical activity can include casual walking, moving around the home or standing.
Moderate to vigorous activity includes movement such as brisk walking, where breathing and heart rate increase.
Kara Whitaker, associate professor in the department of health, sport, and human physiology at Iowa and corresponding author of the study, said: “We are identifying the optimal composition of movement behaviours across the day associated with the lowest risk of developing HDP and the most improved health outcomes.
“This blueprint holds for each and every trimester of pregnancy.”
Study participants were enrolled at sites in Iowa City, Pittsburgh and Morgantown, West Virginia.
The women wore activity and sleep monitors for at least one week during each trimester of pregnancy.
Four in five participants were non-Hispanic white and nearly a quarter lived in rural areas.
The data showed a steep rise in risk among pregnant women who were sedentary for more than 10 hours a day.
Women who increased light physical activity to at least four hours a day reduced their risk of hypertensive disorders of pregnancy to 15 per cent from 30 per cent.
Whitaker said: “Just moving around more seems to have significant health benefits.
“And I think it also may be a more feasible target for women who are pregnant who are not exercising regularly.”
The researchers said they were surprised that longer durations of moderate to vigorous physical activity did not appear to provide additional benefit.
Sleep beyond a certain duration also did not appear to bring major further benefits.
Whitaker said: “Through this study, we are providing evidence that reducing sedentary behaviour and engaging in light physical activity are important, and maybe more important, when it comes to pregnancy and health.”
The findings may be relevant beyond pregnancy because clinical research has shown that women who develop hypertensive disorders of pregnancy are more than twice as likely to develop heart disease later in life.
Cardiovascular disease includes conditions affecting the heart and blood vessels, such as heart disease and stroke.
Whitaker said: “We know that cardiovascular disease is the number one killer of women, and if we can intervene in pregnancy and prevent women from developing a hypertensive disorder of pregnancy, we are putting them on a better trajectory, away from cardiovascular disease and toward more optimal cardiovascular health.”
The study was published online on June 10.
A second study, published online on May 27, looked more closely at the ratio and type of sedentary behaviour and light physical activity linked to a lower risk of hypertensive disorders of pregnancy.
Whitaker is a lead co-author on that study.
Co-authors in the June 10 study include Alex Crisp, Jaemyung Kim, Karina Smith, Donna Santillan, Mark Santillan and Bridget Zimmerman, from Iowa; Jacob Gallagher, from Iowa State University; Melissa Jones, from Oakland University in Michigan; Bethany Barone Gibbs, Katrina Wilhite, Alexis Thrower and Iqra Sheikh, from West Virginia University; and Sabera Rahman, Janet Catov, Christopher Kline and Maisa Feghali, from the University of Pittsburgh.
The National Institutes of Health, the University of Iowa Institute for Clinical and Translational Science, the University of Pittsburgh Clinical and Translational Science Institute and the West Virginia Clinical and Translational Science Institute funded the research.
We are excited to reveal the winners of the third annual Femtech World Awards.
The winners were announced at a virtual event this afternoon attended by shortlisted companies, along with sponsors and judges.
The event welcomed guests from the UK, Europe, Asia, Africa and North America.
Thank you to all 174 entries, as well as the sponsors for making the event possible.
See you in 2027!
Femtech World Awards 2026 Winners
Winner:
Shortlisted:
IVI RMA x Juno Genetics
Natural Cycles
Winner:
Highly commended:
U-Ploid
Shortlisted:
Hello Inside
Winner:
WISE HF, led by Prof. Mary Ryder
Highly commended:
Cardiac College for Women
Shortlisted:
Hyvelle Ferguson-Davis
CognitiveCare
Winner:
Highly commended:
Youterus
Shortlisted:
ŌURA
Winner:
Shortlisted:
LeanShield by ParrotPal Group
Perigen
Winner:
Shortlisted:
Body Moody
Looop
Winner:
Shortlisted:
Owning Your Menopause
Womeno
Winner:
Shortlisted:
The Blue Box
Celbrea
Winner:
Shortlisted:
HealCycle
Mor
Winner:
Shortlisted:
HRC Fertility
Mira
Pregnant women’s expectations about postpartum sleep may predict sleep quality after birth, outweighing prior sleep and psychiatric history, a study suggests.
The findings suggest attitudes and beliefs about sleep during pregnancy could be a modifiable risk factor for postpartum sleep concerns.
They also indicate that, among women expecting the poorest sleep, higher postpartum anxiety may further worsen sleep quality.
Sammy Dhaliwal, lead author is clinical health psychologist and research fellow in the department of obstetrics and gynaecology at the Perelman School of Medicine at the University of Pennsylvania.
Dhaliwal said: “Most pregnant women in our sample anticipated poor postpartum sleep before it occurred, and it was striking that those expectations predicted worse sleep outcomes even after accounting for factors such as prior sleep disorders, psychiatric history, and number of previous births.
“This suggests that attitudes and beliefs about sleep during pregnancy may represent a modifiable target for early intervention before postpartum sleep problems emerge.”
Sleep disturbance affects an estimated 60 to 80 per cent of postpartum women and is linked to a higher risk of depression and anxiety.
Researchers said it is often regarded as an expected part of life after childbirth rather than a health issue that may be addressed earlier.
The study enrolled 432 pregnant women at about 24 weeks of gestation, meaning around 24 weeks into pregnancy.
Participants completed measures of their expectations about postpartum sleep, current sleep quality using the Pittsburgh Sleep Quality Index, and mood using validated depression and anxiety scales.
Assessments were repeated at six, 12 and 24 weeks postpartum.
A subset of 49 women also wore wrist actigraphy devices at six to eight weeks postpartum.
Actigraphy uses a wearable device, similar to a watch, to estimate sleep and wake patterns based on movement.
The results showed that 70 per cent of pregnant women, or 301 of 432 participants, expected poor sleep in the postpartum period.
Researchers found that predicted sleep disruption during pregnancy was a significant predictor of postpartum sleep concerns.
Among first-time pregnant women without prior health concerns, those who expected greater sleep disturbance had significantly more disrupted sleep after birth, measured by both actigraphy and self-report.
Among women who expected the worst sleep quality, higher postpartum anxiety significantly worsened both measured sleep and self-reported sleep, independent of anxiety levels during pregnancy.
Dhaliwal said the findings point to two possible areas for intervention: addressing sleep-related beliefs during pregnancy and treating postpartum anxiety.
Dhaliwal said: “Postpartum sleep disruption is often treated only after problems develop, but our findings suggest there may be an opportunity to intervene earlier during pregnancy.
“Addressing sleep-related beliefs and postpartum anxiety during prenatal and postpartum care may help improve sleep and emotional well-being in new mothers.”
Menopause3 weeks agoPerimenopause misinformation ‘putting women at risk’
Hormonal health3 weeks agoNHS urged to update website following renaming of PCOS
News2 weeks agoWomen still being failed when they reach menopause, experts say
Events2 weeks agoWomen’s Health Innovation Summit opens submissions for 2026 Innovation Showcase
Insight1 week agoBritish women among angriest in Europe, health survey reveals
News2 weeks agoThree menopause innovators shortlisted for Femtech World Award
Fertility4 weeks agoAI could transform ovarian care through personalisation, study finds
News3 weeks agoLow insulin diet and avoiding four food groups may prevent menopause weight gain