Women considering a long-term contraceptive implant are being warned of potential threats to their fertility after seven difficult removals were reported in just four months.
Some 20,000 women are estimated to be using the government-subsidised Jadelle implant, for which two 43 millimetre-long rods are inserted beneath the skin on the upper-inner arm.
It provides close to 100 per cent effective pregnancy prevention for up to five years, with fertility returning when the rods are removed.
But from January to May this year, seven incidents of "location-type problems" with Jadelle - where the implant was difficult to take out or even locate - were reported to the Centre for Adverse Reactions Monitoring in Dunedin.
A further four issues were identified with Jadelle's predecessor Implanon from November 2009 to April 2010.
The UK's Medicines and Healthcare Regulatory Agency has reported 36 instances of Implanon devices migrating from their original location until August 2012, with five cases of infertility when the implant was unable to be found at all.
Family Planning national medical advisor Dr Christine Roke said issues removing the implant were likely to be more frequent than indicated by Carm.
"I think doctors in practice often just get on with it and forget to report these things," she said.
Dr Roke said the likelihood of one being unable to be removed at all was minute.
"We've seen some where they've been difficult [to locate], but I've certainly not come across any that we haven't been able to find with ultrasound.
"I expect it has happened, but we are talking about something extraordinarily rare - but obviously quite troublesome.
"If you can't find it with ultrasound, it's hard to know what to do next."The best advice is to go to somebody who is experienced at putting them in and taking them out, because clearly you're likely to get a better deal.
"If you can feel it in your arm, it's there and it's working. It's only if you can't feel it that it becomes a bit more problematic."
But no assurance is enough for Tauranga resident Leah Hocken, who said her experience of having her Implanon implant removed was "horrendous".
She had it inserted at Family Planning in April 2010, but had it taken out just eight months later due to ongoing side effects.
Not only had the implant moved half an inch, it had also formed a pocket of scar tissue.
"It took about 50 minutes because the nurse couldn't get it to pop out through the hole she was trying to cut in the scar tissue.
"They ended up having two nurses come in: one of them to cut, and one of them to put pressure on the bottom of my arm to pop it out.
"They minced my arm completely."
Miss Hocken was left with a centimetre-square scar on her inner-upper arm, which she has had covered with a tattoo.
"They pretty much just said that was one of the risks that I chose to take by getting it put in."
A spokesman for the Health Ministry said Medsafe was "aware" that contraceptive implants had been associated with removal difficulties.
"The prescribing information . . . advise that women should be informed of these risks prior to insertion . . . [and] health professionals inserting the implants must be trained in their insertion and removal."
- The Dominion Post
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