Copper IUD experiences nearly always come down to the same thing: your period gets heavier, and often longer. For most women that eases after three to six months as your body adjusts to the copper. What most articles leave out is that heavier bleeding costs iron, and iron is measurable.
I think that is a real gap. You choose a copper IUD precisely because you want no hormones, which makes an iron value the one number still telling you how your body is handling it.
What is a copper IUD and how does it work?
A copper IUD is a small T-shaped plastic device wound with copper wire, placed in your uterus by your GP or gynaecologist. It releases copper ions, which make the cervical mucus and the uterus inhospitable to sperm, so fertilisation almost never happens. It contains no hormones.
Depending on the type, a copper IUD lasts 5 or 10 years. According to Thuisarts.nl it is more than 99 percent reliable against pregnancy, which puts it among the most reliable methods available. There is nothing to remember daily.
That is exactly why women choose it. No pill to forget, no hormones touching your mood or libido, and your own cycle simply carries on.
Do you still ovulate with a copper IUD?
Yes. A copper IUD does not suppress ovulation. Your cycle stays yours, with a normal rise in oestradiol and progesterone, and you ovulate as you would without contraception. The copper acts later in the process, inside the uterus. That is also why your period keeps coming.
For some women that is the whole point. You still feel your cycle: the energy mid-month, the tender breasts beforehand, the mood that moves with it. Women who want to know what their own rhythm feels like after years on the pill often end up here.
It also means a hormone test stays usable. On the combined pill you mostly measure the pill. With a copper IUD you measure yourself, as long as you draw blood at the right point in your cycle. There is more on this in our article on birth control and your hormones.
What is the difference between a copper IUD and a hormonal IUD?
The difference is the direction they push your period. A copper IUD usually makes bleeding heavier. A hormonal IUD almost always makes it lighter, and in some women the period stops altogether. Both are highly reliable; they simply suit different bodies and different wishes.
| Copper IUD | Hormonal IUD | |
|---|---|---|
| Hormones | None | Levonorgestrel, local |
| Period | Often heavier and longer | Often lighter, sometimes absent |
| Ovulation | Continues | Usually continues, sometimes suppressed |
| Lasts | 5 to 10 years | 5 to 8 years |
| Effect on iron | Can draw on your stores | Can protect your stores |
| Often suits | Women wanting no hormones | Women with heavy periods |
Picture two women of 34, both done with the pill. One has a light three-day period and picks copper, because it can afford to get heavier. The other already changes a tampon every two hours and picks the hormonal IUD, because copper would make her problem bigger. Same method, opposite advice.
How long do you bleed after a copper IUD is fitted?
Expect an unsettled stretch of three to six months. During that time you may have spotting between periods, and your periods are often heavier and a day or two longer than you were used to. For most women it then settles into a new, predictable pattern.
Cramping belongs to those first cycles too. It is usually strongest around the fitting itself and in the first two periods afterwards.
If bleeding is still heavy enough after six months to disrupt your daily life, that is a reason to go back to your GP. Not a reason to push through. What heavy actually means is covered in our article on heavy periods.
Heavier bleeding and your iron: what you can measure
More blood loss per cycle means more iron loss per cycle. Research in Contraception in 1995 measured both menstrual blood loss and iron status in women with a copper IUD, and saw the two move together. That is why a copper IUD and an iron value belong in the same conversation.
Ferritin is the value that responds first. It is your iron store, and it falls before your haemoglobin shows anything. You can therefore have a perfectly normal Hb while your store quietly empties. Symptoms that fit include tiredness, breathlessness on stairs, hair loss and cold hands.
Sound familiar? The Iron status test from Lunara measures ferritin, iron and transferrin among others, with an assessment by a BIG-registered doctor. What the numbers mean is covered in our article on ferritin levels.
Who does a copper IUD suit less well?
A copper IUD suits you less well if you already bleed heavily or for a long time, or if you have a history of anaemia. It pushes in the wrong direction. With an untreated infection, unexplained bleeding or an unusually shaped uterus, your doctor will look at something else first.
The risks around fitting are small but real. The device can move out of place, more often in the first year and more often shortly after childbirth. Perforation of the uterine wall happens in roughly 1 in 1,000 fittings according to Thuisarts.nl, and somewhat more often while breastfeeding.
What a copper IUD does not do is protect against STIs. That needs condoms, whichever IUD you carry.
Frequently asked questions
Is Mirena a copper IUD?
No. Mirena is a hormonal IUD containing levonorgestrel. Copper IUDs carry names like T-Safe, Multiload or Flexi-T and contain no hormones. Both are called a coil, which explains the confusion.
Which copper IUD is best?
There is no best one. Types differ in copper surface, shape and lifespan, and your doctor also chooses on the shape and size of your uterus. A model with more copper often lasts longer.
Can you feel the copper IUD during sex?
Usually you cannot. A partner sometimes feels the threads. Those are often trimmed shorter at a check-up if they get in the way.
How quickly can you get pregnant after removal?
There is no waiting time built in. Because ovulation was never switched off, pregnancy can happen in the first cycle after removal.
A copper IUD is one of very few highly reliable methods that leaves your hormones alone. You usually pay for that freedom with a heavier period, and that is a fair trade as long as your iron stores keep up. Discuss your bleeding and your iron values with your GP if you notice your tiredness no longer lifts.
Every blood test result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP.
References
- Thuisarts.nl. Choosing a copper IUD. Accessed 2026.
- NHG Guideline on Contraception. Dutch College of General Practitioners. Accessed 2026.
- Milsom I, Andersson K, Jonasson K, Lindstedt G, Rybo G. The influence of the Gyne-T 380S IUD on menstrual blood loss and iron status. Contraception, 1995. PMID 7587189.
- Janssen CA, Scholten PC, Heintz AP. The effect of low-dose 3-keto-desogestrel added to a copper-releasing intrauterine contraceptive device on menstrual blood loss. American Journal of Obstetrics and Gynecology, 2000. PMID 10739510.
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