Clinical experience with intrauterine devices in a private practice

Migration of intrauterine devices: radiologic findings and implications for patient care

Intrauterine devices (IUDs) are a commonly used form of contraception worldwide. However, migration of the IUD from its normal position in the uterine fundus is a frequently encountered complication, varying from uterine expulsion to displacement into the endometrial canal to uterine perforation. Different sites of IUD translocation vary in terms of their clinical significance and subsequent management, and the urgency of communicating IUD migration to the clinician is likewise variable. Expulsion or intrauterine displacement of the IUD leads to decreased contraceptive efficacy and should be clearly communicated, since it warrants IUD replacement to prevent unplanned pregnancy. Embedment of the IUD into the myometrium can usually be managed in the outpatient clinical setting but occasionally requires hysteroscopic removal. Complete uterine perforation, in which the IUD is partially or completely within the peritoneal cavity, requires surgical management, and timely and direct communication with the clinician is essential in such cases. Careful evaluation for intraabdominal complications is also important, since they may warrant urgent or emergent surgical intervention. The radiologist plays an important role in the diagnosis of IUD migration and should be familiar with its appearance at multiple imaging modalities.

Contraindications to IUD and IUS use

Contraindications to IUD or IUS use can be found on product labeling, in the guidelines of various specialty groups and in recommendations from peer-reviewed articles. Overly restrictive contraindications block access to this top-tier method for many women who would be candidates based on current scientific evidence. Assuming that a condition should be listed as a contraindication only if the risk of IUD/IUS use by a woman with that condition exceeds her risk with pregnancy, the list of contraindications is reduced to pregnancy, active uterine infection, malignancy in the uterus or cervix, an inability to place or retain the device, unexplained abnormal bleeding and adverse reaction to product ingredients.

Return of fertility in nulliparous women after discontinuation of the intrauterine device: comparison with women discontinuing other methods of contraception

OBJECTIVE

To clarify the effect of the using the intrauterine device on fertility in nulliparous women.

DESIGN

Prospective cohort study of two groups of nulliparous women, one recruited while using an intrauterine device and the other while using an oral contraceptive.

SETTING

Seventeen family planning clinics in England and Scotland.

SAMPLE

1,071 nulliparous, married women, aged 18-40 years, 558 of whom contributed information to the main objective of the study.

METHODS

The women were recruited between 1982 and 1985 and followed up annually to 1994. Dates and reasons for any contraceptive method changes (which were most frequently to barrier methods) were recorded, together with the outcome of any pregnancies, at each follow up.

MAIN OUTCOME MEASURES

The number of nulliparous women giving birth at term after stopping contraception (oral contraceptive, intrauterine device or barrier method) in order to conceive.

RESULTS

Women who stopped using a barrier method to achieve a planned pregnancy conceived most quickly: 54% were delivered after one year vs 39% of intrauterine device and 32% of oral contraceptive users (log rank P = 0.002). There was no association between fertility and duration of oral contraceptive use: However, short term intrauterine device users (< 42 months) showed a fertility pattern more favourable than seen in those discontinuing oral contraceptives, with increasing duration of intrauterine device use being associated with decreasing fertility (linear trend P = 0.005); the fertility of women who had used the intrauterine device for 78 + months was the most impaired (28% were delivered by 12 months vs 46% of short term users; at 36 months the corresponding figures were 79% vs 91%). This association remained after adjusting for potential confounding factors, including maternal age, husband's social class, and history of gynaecological illnesses, factors which themselves had independent associations with fertility.

CONCLUSIONS

Long term intrauterine device use in nulliparous women appears to be associated with an increased risk of fertility impairment.

Intrauterine devices and pelvic inflammatory disease: meta-analyses of published studies, 1974-1990

We conducted a meta-analysis of 36 papers published between 1974 and 1990 to estimate the effects of intrauterine device (IUD) use and Dalkon Shield use, in particular, on pelvic inflammatory disease (PID). The number of women studied in each report ranged from 50 to 26,507. For general IUD use, analyses were separated by type of PID (symptomatic or asymptomatic) because of extreme rate-ratio heterogeneity across studies. Dalkon Shield rate ratios were more homogeneous and were considered in a single meta-regression. There was substantial heterogeneity, however, in all three meta-regressions; the rate-ratio estimates ranged from 0.51 to 12 for IUD use and symptomatic PID, from 1.0 to 132 for IUD use and asymptomatic PID, and from 0.32 to 28 for Dalkon-Shield use and PID. This heterogeneity appeared to be due to differences in reference groups, study populations, and characteristics of study design. We observed consistent, positive associations of IUD use with both symptomatic and asymptomatic PID. These associations were largest for the Dalkon Shield.

Was the Dalkon Shield a safe and effective intrauterine device? The conflict between case-control and clinical trial study findings

OBJECTIVE

To compare the findings of the case-control and cohort studies used to indict the Dalkon Shield (A.H. Robins Company, Inc., Richmond, VA) with the findings of the Dalkon Shield clinical trials.

DATA IDENTIFICATION

All published reports on the Dalkon Shield were identified through MEDLARS system (United States National Library of Medicine) searches and by cross checking all references in these reports. The same approach was used to identify all case-control and cohort studies of the purported relationship between intrauterine devices (IUDs) and pelvic inflammatory disease (PID).

STUDY SELECTION

Only studies of interval patients that included 50 or more women and 6 or more months of follow up that computed standard IUD event rates (rates of pregnancy and expulsion and removal for pain and bleeding) were selected for this study. All case-control and cohort studies identified were included except two case-control studies that included women with sterile chronic salpingitis.

RESULTS

The 16 case-control and 2 cohort studies found or suggested that the Dalkon Shield increased the risk of PID. The 71 clinical trials of the Dalkon Shield show that when this device is inserted by an experienced clinician it is a safe and effective contraceptive method, comparable with other IUDs used at the time. There was no evidence of an increased risk of PID found in these clinical trials.

CONCLUSIONS

This study offers convincing evidence that the indictment of the Dalkon Shield was a mistake. Additionally, this study shows that physician skill and experience is far more important to successful IUD insertion than previously recognized, a finding with considerable implications for IUD study designs and for marketing strategies.

Copper IUDs, PID, and fertility in nulliparous women

Some authors have suggested that use of IUDs (intrauterine contraceptive devices) in nulliparous women should be contraindicated because of the risk for PID (pelvic inflammatory disease); others have found nulliparous women to be suitable candidates for IUD use. Clinical studies of copper IUDs in which parous and nulliparous women have been compared with regard to risk of PID often point to young age as a risk factor, regardless of parity. Vital statistics of PID rates also show this trend. An overall PID rate of 1.49/100 woman-years (WY) was calculated from data contained in 28 of the clinical studies reviewed in this paper. These studies included 25,674 women, of whom 42.5% were nulliparous. Studies of fertility following use of copper IUDs indicate that fertility is not impaired by their use.

Safety of intrauterine contraception

Some of the risks which have been associated with the use of intrauterine contraception are reviewed. For users of copper-releasing IUDs, such as the Multiload Cu375 and TCu380, uterine perforations are rare, there is no evidence of an increased risk of infertility, and there probably is no increased risk of ectopic pregnancy after IUD removal. Any increased risk of pelvic inflammatory disease may be limited to the initial months of IUD use. The safety of intrauterine contraception needs to be re-evaluated for the newer IUDs, since most of the information relating to IUD safety is based on studies of devices which are no longer used or which are not in widespread use.

The future of intrauterine contraception

In this review paper some guidelines for IUD use are presented that if followed should reduce the incidence of IUD-related complications. Recent IUD developments are discussed including the levonorgestrel-releasing T, a new variation of the Multiload, and IUDs designed for postpartum insertion. Since significant improvements in IUD safety will most likely result from a better understanding of IUD-related side-effects and adverse reactions, the paper includes recommendations for future IUD research that could enhance the safety, effectiveness and acceptability of available IUDs.

Pregnancy after IUD use

Much has been written about the risks of PID to IUD users, but very little about the subsequent fertility status of these patients. Is tubal infertility increased in an IUD user who has been asymptomatic? Does the addition of copper make the device harmless? Was the Dalkon Shield so harmful in the nulliparous woman? Our study (89 and 90% follow-up after 12-14 years) of 200 Dalkon Shield and 142 TCu-200 users allows us to answer 'No' to the three previous questions. We conclude that wearing an IUD per se does not cause infertility since all our patients who had IUDs removed for intended pregnancy did become pregnant; the addition of copper per se does not make an IUD safer although it does make it more efficient; the Dalkon Shield used in nulligravidas was not more dangerous than other types of IUD.