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Long-acting reversible contraception (LARC) is the collective name for intrauterine contraception (copper intrauterine devices and levonorgestrel intrauterine systems) and the subdermal contraceptive implant. LARC methods are highly effective, require minimal user effort and do not require regular healthcare appointments; however the insertion and removal procedures can only be undertaken by clinicians trained to do so. The progestogen-only subdermal implant is the most effective method of reversible contraception in the United Kingdom and is licensed for 3 years. The copper intrauterine device is the most effective non-hormonal method of contraception. These devices are licensed for five or 10 years and can also be used as emergency contraception. The levonorgestrel intrauterine systems (LNG-IUS) are licensed for 3, 5, or 6 years. The Mirena LNG-IUS is also licensed for use in treating heavy menstrual bleeding and for endometrial protection as part of hormone replacement therapy.  相似文献   
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Objective

Researchers traditionally rely on participant self-report for contraceptive use. We hypothesized that self-reported contraceptive use by clinical research participants may disagree with objectively measured hormonal status.

Study design

We enrolled women in Harare, Zimbabwe, aged 18–34, who by self-report had not used hormonal or intrauterine contraception for >30 days, or depot medroxyprogesterone acetate for >10 months, into a study designed to assess biologic changes with contraceptive initiation and use. Blood samples obtained at enrollment and each follow-up visit (N=1630 from 447 participants) were evaluated by mass spectrometry for exogenous hormones. We individually interviewed a subset of participants (n=20) with discrepant self-reported and measured serum hormones to better understand nondisclosure of contraceptive use.

Results

Discrepant with self-reported nonuse of hormonal contraception, synthetic progestogens were detectable in 120/447 (27%, 95% confidence interval 23%–31%) enrolled women. Measured exogenous hormones consistent with use of contraceptive pills (n=102), injectables (n=20) and implants (n=3) were detected at enrollment, with 7 women likely using >1 contraceptive. In-depth interviews revealed that participants understood the requirement to be hormone free at enrollment (100%). Most (85%) cited partner noncooperation with condoms/withdrawal and/or pregnancy concerns as major reasons for nondisclosed contraceptive use. All interviewed women (100%) cited access to health care as a primary motivation for study participation. Of participants who accurately reported nonuse of hormonal contraception at enrollment, 41/327 (12.5%) had objective evidence of nonstudy progestin use at follow-up that disagreed with self-reported nonuse.

Conclusions

Women joining contraceptive research studies may misrepresent their use of nonstudy contraceptive hormones at baseline and follow-up. Objective measures of hormone use are needed to ensure that study population exposures are accurately categorized.

Implications statement

Among Zimbabwean women participating in a contraceptive research study, 27% had objective evidence of use of nonstudy contraceptives at enrollment that disagreed with self-report. Studies that rely on self-report to identify contraceptive hormone exposure could suffer from significant misclassification.  相似文献   
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Imaging of intrauterine contraceptive devices.   总被引:1,自引:0,他引:1  
OBJECTIVE: Intrauterine contraceptive devices (IUDs) are reemerging as common methods of birth control in the United States. Imaging, especially sonography, has an important role in their evaluation. This review illustrates the normal and abnormal imaging appearances of IUDs. METHODS: We describe and illustrate the appearance of different types of IUDs on different imaging modalities as well as radiologically relevant complications associated with IUDs. RESULTS: On sonography, the IUD should be visualized as centrally located within the endometrial cavity, with the crossbar (if present) in the fundal portion of the endometrial cavity. Some older patients have IUDs in place that are no longer commonly used, such as the Lippes Loop (Ortho Pharmaceutical, Raritan, NJ) and Saf-T-Coil (Julius Schmid Laboratories, Little Falls, NJ), which have a pathognomonic appearance. Newer IUDs, such as the early version of the Mirena IUD (Leiras Oy, Turku, Finland), may be difficult to visualize on sonography. Patients from China frequently have a ring-shaped IUD. Sonography is important in assessing the complications of IUDs, including a low position, associated infection, myometrial migration, uterine perforation, intrauterine or extrauterine pregnancy associated with the IUD, and retention and fragmentation of the IUD. If an IUD is known to be present but not visualized sonographically, plain radiography is helpful in assessing the location. Computed tomography and magnetic resonance imaging are not typically used to assess IUDs, but the appearances of IUDs should be recognized with these modalities. CONCLUSIONS: Imaging, specifically sonography, has a crucial role in the evaluation and management of IUDs and associated complications.  相似文献   
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目的:探讨宫内节育器异位的原因、诊断方法,分析IUD异位的危险因素、处理方法。方法回顾性分析42例节育器异位的临床资料。结果爱母环占61.90%(26/42),O形环占28.57%(12/42),T环形占4.76%(21/42),吉妮环占4.76%(2/42);爱母环发生异位的机率明显高于其它类型节育器;位于子宫肌层内30例,穿破浆膜层4例;子宫外异位:位于盆腔内6例,阔韧带后叶3例;爱母环的一条金属臂穿入乙状结肠1例,穿入宫旁1例,1例位于右上腹大网膜内,1例位于肠管表面。取器方式利用宫腔镜、腹腔镜、宫腹腔镜联合、膀胱镜及开腹等方式,均成功。有随访记录的14例占33.4%,其中,术后1+月随访3例占7.1%,1年内随访者有12例占21.4%,3年内随访者2例占4.8%,无随访者28例占66.7%。节育环异位穿孔率无随访者高于有随访记录者。在节育器异位患者中,上环后有再次妊娠15例占35.7%。结论选择合适的节育器,适宜的安环时间可减少节育器异位的发生。充分术前评估,选择适宜的手术方式、及时、合理转换术式是取环成功的关键。  相似文献   
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Objective

To examine self-reported professional practices of postpartum contraceptive counselling at Finnish community health centres.

Design

A survey study with self-administered online questionnaires.

Setting

All local municipalities (n = 107) in the Expert Responsibility Area of Tampere University Hospital in Western Finland in 2005.

Subjects

A total of 69 (64% of 107) health centre physicians and 80 (75%) nurses performing postpartum check-ups.

Main outcome measures

Contraceptive method most often initiated or recommended to breastfeeding women at postpartum visit; timing of postpartum initiation of hormonal and intrauterine contraceptive methods in relation to breastfeeding and resumption of menses.

Results

The most common contraceptive method initiated or recommended to breastfeeding women by both physicians (41%) and nurses (45%) was the condom, followed by progestin-only pills and intrauterine contraception. Few professionals recommended breastfeeding (lactational amenorrhea) as the only contraceptive method. Only eight (12%) physicians inserted a copper-releasing intrauterine device and five (7%) a levonorgestrel-releasing intrauterine system typically at the postpartum visit; the majority delayed the insertions until the resumption of menses. Fifty-three (77%) physicians initiated combined oral contraceptives mostly when breastfeeding was terminated and menses had returned. Over half of the municipalities involved in the study did not provide any medical contraceptives free of charge postpartum.

Conclusion

Professionals’ reports indicate that initiation of effective contraceptive methods is delayed after childbirth. In order to promote better postpartum contraception practices, updated evidence-based guidelines are needed.  相似文献   
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Sulak P  Willis S  Kuehl T  Coffee A  Clark J 《Headache》2007,47(1):27-37
OBJECTIVE: The aim was to assess the timing and severity of self-reported headaches in patients utilizing a standard 28-day oral contraceptive (OC) cycle consisting of 21 hormone (estrogen + progestin)-containing pills and 7 placebo pills (ie, 21/7-day cycle) converted to a placebo-free extended OC regimen. METHODS: An open label single-center prospective analysis of headaches recorded daily on a severity scale of 0 to 10, along with the headache item of the Penn Daily Symptom Rating (DSR17) and a weekly modified Migraine Disability Assessment (MIDAS) headache questionnaire, during standard 21/7-day cycles followed by a 168-day extended placebo-free regimen of an OC containing 3 mg of drosperinone and 30 mcg of ethinyl estradiol (DRSP/EE). RESULTS: Of the 114 patients who began the trial, 111 completed the 21/7-day cycle portion of the study. Based on the headaches scales, there were significant differences in headache severity among the 28 days of the standard 21/7 cycles (P < .001). Greater headache severity occurred on days 25 through 28 during the 7-day placebo interval of the 21/7 cycles (P < .05). Of the 111 patients who completed the 21/7 phase of the study, 102 (92%) completed the 168-day extended placebo-free OC regimen. During the first 28 days of the extended placebo-free regimen, daily headache scores decreased (P < .0001) compared to those of the previous 21 active/7 placebo day cycle. The difference on a daily basis was first detected on extended cycle days 25 through 28 (P < .0001) and persisted throughout the remainder of the 168-day regimen. Subjects were divided into 2 groups (severe and mild) based on the median of the total headache score during the 21/7 OC cycle. The group with higher total headache scores demonstrated a significant (P < .0001) reduction in daily headaches beginning in the first 28-day interval of the extended placebo-free regimen, persisting throughout the entire 168-day extended regimen. In contrast, the group with the lower total headache score remained unchanged (P= .79) throughout the extended regimen. Impact of headaches on work, family, and social functions also improved on the extended placebo-free regimen in 6 of 8 measures (P < .05) assessed by weekly headache questionnaires. CONCLUSION: Compared to a 21/7-day OC regimen, a 168-day extended placebo-free regimen of DRSP/EE led to a decrease in headache severity along with improvement in work productivity and involvement in activities. This is a preliminary study and results may not be widely generalizable.  相似文献   
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