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A comparative study of the clinical performance of two copper-releasikg IUDs, NOVA-T & copper-T-200 in Lagos, Nigeria
CONTRACEPTION A CCBPARATIVE STUDY OF TKK CLINICALPERFORMANCE OF TWO COPPER-RELEASIRGIUDr. KOVA-T & COPPER-T-200 IN LAGCS, NIGERIA
MURIELA. OYEDIRAN,I.B.B.S.,MPH Department of Community Health College of Medicine University of Lagos, Nigeria
OLADELE AKINLA, F.R.C.S.,M.R.C.O.G. Department of Obstetrics and Gynaecology College of Medicine University of Lagos, Nigeria
ABSTRACT
A non-randomisedstudy was performed to compare the useeffectivenessof the Copper-T-200and Nova-T intrauterinedevices. It was found that generally, results compared favourably with other world-wide studies. No accidental pregnancieswere experienced and no significant difference was found between the expulsion rate of the Nova-T (5.0) and that of the Copper-T-200 (6.5) and the removal rates for bleeding and pain, which were 1.5 and 3.8, respeotively. The continuationrate for the Nova-T was 91.3 compared with 88.2 for the Copper-T. The total experiencewas based on 815 woman-monthsof use,
Accepted for publication July 15, 1980
AUGUST
1980VOL.22N0.2
115
CONTRACEPTION INTRODUCTION The Copper-T-200 intrauterine device extensively in many countries (1,2,3,5,6,7) use throughout the world.
(IUD) has been tested and is now in general
However Copper IUDs have not been used extensively in Nigeria because the Lippes loop, first introduced to the country in 1964
by its Family Planning Council, has been the most popularly used and most easily available IUD up until now. In view of the fact that several studies have shown the advantages of the Copper-T over the Lippes loop, with regard to the continuation rate, expulsion rate, accidental pregnancy rate, and rate of removals for bleeding and pain (4,6,9), it was decided to test the CU-T-200 on patients attending the Family Planning Clinic of the Department of Community Health of the College of Medicine, University of Lagos. At the same time, a new copper device called the Nova-T had recently been introduced in Finland end one of us (O.A.) brought some to Lagos. It was decided to compare these two forms of the copper device in the same clinic population. The study was performed with a view to establishingwhether there were any variations in results compared with reported experiencesfrom other countries.
METHODS _.-One-hundred-and-thirty-two women attending the Family Planning Clinic, and who had choSeA the IUD as their method of contraception, were included in the non-randomisedtrial. The insertions of the Copper-T-2C0 and the Nova-T were performed initially by two physicians (O.A. and a Senior House Officer), then by one physician only (M.A.O.). The insertionswere performed during a menstrual period or within one or two days post-menstrually. Sixty-five women had the Nova-T inserted and 67 had the Copper-T-200. The principal differences between the Nova-T and the Copper-T-200 (Fig. 1 and 2) are as follows: The junction of the horizontal and vertical arms in the Nova-T is curved enabling the Nova-T to retain its memory more easily after insertion; perforation or penetration of the cervical tissue is eliminatedby increasing the surface area of the Nova-T at the end of the vertical arm which is formed in a loop; the horizontal arms of the Nova-T are directed upwards when loaded into the inserter, while the horizontal srms of the Copper-T-200 are directed downwards, which leads to a variation in insertion technique such that when the Copper-T device and inserter tube are inserted into the uterine cavity, retraction of the inserter tube releases the arms of the device aAd also places it at the fundus of the uterus (12), whereas with the Nova-T, retraction of the inserter tube releases the arms of the deviceonly, it then requires to be positioned at the fundus of the uterus by the extra procedure of pushing it up into position with the inserter techniques and methods of withdrawal of tube - the pre-insertion the inserter tube and plunger are,however,the same for both devices;
116
AUGUST
1980 VOL. 22 NO. 2
CONTRACEPTION
Fig.
1
,;,,;~~--.‘~..2f,(1 .J
Fig. 2 Nnvd-T
AUGUST
1980 VOL. 22 NO. 2
117
CONTRACEPTION
the rounded hemispheres of the Nova-T also cover the edges of the inserter so that a rounded sphere is presented when insertion occurs and this gives an easier and less painful insertion - there is also less risk of penetration of uterine tissue because of the beaded ends of the horisontal arms; and ?.astly,by incorporating a silver core in the centre of the copper wire used in the Nova-T, it is hoped to extend its life. The life table method described by Tietre & Lewitt (11) was used in the analysis of the data.
RBSULTS Age Distribution: Table I Age Distributionof the Women in the Studg
NOVA-T
Cu-T
Total
P value
.--7q-7
Age
No.
20.24
3
4.6
8
6.1
0.25
25-29
12
18.5
28
21.2
0.66
30-34
17
26.1
47
35.6
0.24
35 +
33
50.8
49
37.1
0.12
65 t-k
100.0
%
I
67 I loo.0
Worn Table I it is seen that the age distributionbetween the two groups of wmen using either the Nova-T or Copper-T-EC0did not vary significantly. No woman under the age of 20 was fitted with an IUD, and over 70% of the patients who were fitted were over 30 years in both groups. The lowest number of insertions was in the 20 - 24 year group for both Nova-T and Copper-T-200.
118
AUGUST
1980 VOL. 22 NO. 2
CONTRACEPTION Parity: Table II Distributionof Parity of the Women Using the Nova-T & Cu-T-200 IUDs Cu-T
Nova-T Parity
No.
Total
No.
5
I1
No.
0
1.5
3
1
1.5
3
2
16.4
16
80.6
110
3+
k
2.3
2.3
12.1
83.3
:
65
100.0
I
I
67
I 100.0
I
132
I
1 loo.O(
The majority of women (over 8% in both groups)had had three or more live births. Only 6.s of the women who had the Nova-T and 3% of those using the Copper-T-200 had fewer than two children (Table II). TerminationRates: Table III --Ret Cumulative TerminationRates per 100 Yoren at 12 Months (with 9%
lower and uooer confidence limits)
T
Nova-T Type of Termination
Rate
LL
UL
1
Cu-T
Rate
LL
UL
pregnancy Expulsion
5.0
1.1
14.5
6.5
1.8
16.6
Bleeding/Pain
1.5
0.4
8.4
3.8
1.0
9.7
Other Personal
2.2
0.3
7.9
1.5
0.2
5.2
Total Terminations
8.7
1.8
30.8
11.8
3.0
31.7
91.3
98.2
69.2
88.2
97.0
68.3
Other Medical Planning Pregnancy
Total Continuations
AUGUST
1980VOL.22N0.2
119
CONTRACEPTION In this series althougil the total 815 women months of use, no pregnancies no removals for “other medical” reasons In the light of the high (Table III). the patients, 8W0 of whom had 3 or more surprising.
experience was only for occurred. There were also or for “planning pregnancy” parity oi the majority of live births, this is not
The expulsion rate for Nova-T was 5.0 compared to 6.5 with the Similarly all other Cu-T, but this difference was not significant. rates were lower for the Nova-T, but more so for bleeaing / pain where only 1.5 removals occurred per 100 women using the Nova-T The continuation rate for the campared with 3.8 for the Cu-T. Nova-T was higher than that for the Cu-T, being 91.3 compareu with However, none of these differences were found to be signi88.2. ficant. DlSCUSSlCn --Pregnancy: No accidental pregnancies were recorded for the 12 months of use for either the Nova-T or the Copper-T-200. It was therefore not possible to come to any conclusion regarding a lower pregnancy In the rate for the Nova-T as found by Luukkainen et al. (2). same study, they also found that the pragnzyxte for the Nova-T was lower in every age and parity group.
Timonen and Luukkainen in another study (3) also showed that the pregnancy rate for the Copper-T-200 declined with increasing parity, while Lewitt (4) observed that accidental pregnancies tended In the light of the above facts, the absence to decline with age. of accidental pregnancies in our study might be related to the fact that 83% of the total clinic population had a parity of over three children and 7% were over the age of 30 years. &ulsion: --._The difference in the expulsion rates in this study, of 5.0 for the Nova-T and 6.5 for the Copper-T-200, was not significant. The comparative study by Luukkainen et al. (I) recorded an expulsion rate of 5.8 for the Nova-T compared with.8 for the Copper-T-EOC but this result was also not statistically significant. The expulsion rate of Copper-T-200 in the Lagos study (6.5) compared favourably with the 7.0 obtained by Tejuja et al. in India (8). Bowever, Pulido and Heasham in Colombia (6) experienced a high expulsion rate of 8.2. The Colombian study however had a clinic population in which only 2%: of the women were over 30 years of age compared with 73% in Lagos. ParitS also varied, with 44% of the Colombian women having more than 3 children, compared with 83$ of the Lagos women. The higher age range and parity of the Lagos women associated with a lower expulsion rate tends to support observations by other researchers that increasing age and parity were associated with declining expulsion rates (4, 2).
120
AUGUST
1980 VOL. 22 NO. 2
CONTRACEPTION Bleeding
ani Pain:
The main medical reason for removal of the Copper-T-200 in a study by Timonen and Luukkainen (3) was for bleeding and/or pain, removals for and this was found to be closely reiated with age; this reason being highest in the age-group under 25. The under 23 age-group was unfortunately under-represented in the Lagos study. with However, the rate of 3.8 in this study compared favourably their rate of 4.0 for all acceptors. In another study by the same authors (l), however, the removal rates for pain and bleeding were high, being 13.9 for the CopperThe reasons for these large values T-200 and 12.3 for the Nova-T. were thought to be due to less well-trained personnel performing insertions, and removals being carried out for the slightest indication. Timonen and Luukkainen (3) recorded that women under 2.5 years of age had a high risk for developing infection regardless of parity, and that removals for other medical reasons were greater in this They also showed that with the Copper-T-200, the removal age group. rate for planning pregnancies showed a high negative correlation These findings are consistent with our findings with age and parity. in which the under 25 age-group because in our clinic population, was under-represented and only formed 6.s of the total clinic population, no removals were experienced for infection, other medical reasons or for planning pregnancies. The continuation rates in the Lagos study of 91.3 for the Nova-T and 88.2 for the Copper-T compared favourably with 72.6 and ::;‘? for the Nova-T and Cu-T, respectively, in Luukkainen’s study Akinla et al. (9) stated that the highest continuation rates in iheir study were found when insertions were done during or This is the policy in the Clinic immediately after menstruation. in which the present research was done, and all insertions were done in the first week of the menstrual cycle. The differences already mentioned earlier, with regard to lower rates of removals for bleeding and pain in the Lagos study compared with the rates in Europe (l), are of significance. Removals for pain and bleeding have been one of the most frequent drawbacks in the use of the Lippes loop in developing countries (10). One of the problems caused by the excessive bleeding is that a potentially anaemic state may becme overt leading to a deterioration in maternal health and well-being. In view of the fact that both the Nova-T and the Copper-T-200 have produced results that are comparable with, and in saae cases better than those obtained in Europe, the addition of the copper IUDs to the armsmentarium of the family planner can only but herald a more favourable attitude to the use of intrauterine devices in developing countries.
1.
Luukkainen, T., Nielsen, N.C., Nygren, Ii. G., Pyorala, T., and Kosonen, A. Randomised comparison of clinical performance of two copper-releasing IUDs, Nova-T and Copper-T-200 in Denmark, Finland and Sweden. Contraception 19: l-9 (1979).
AUGUST
1980 VOL. 22 NO. 2
121
CONTRACEPTION
2.
Luukkainen, T., Nielsen, N. C., Nygren. K. G., Pyorala, T. Combined and national experience of postand Allonen, h. menstrual IUD insertions of Nova-T and Copper-T in a randomised study. Contraception198 11-20 (1979).
3.
The use effectivenessof Timonen, H., and Luukkainen,T. the Copper-T-200 in a simulated field trial. Contraception 9: 1-13 (1974).
4.
Two years Experience with the Copper-T: A Research Lewit, S. Report. Studies in Family Planning 4: 171-172 (1973).
5.
The effectivenessof the Copper-T intrauterine Silvin, I. device. A CoilaborativeStudy in Five Countries. Studies in Family Planning 4: 162-170 (1973).
6.
Tvo-year result of a clinical Pulido M., and Measham, A. R. study of the T-Cu-200 IUD in Colombia. Studies in Family Planning 5: 221-223 (1974).
7.
Tejuja, S., Savena, N.C., Malhotra, LT.,Choudbury, S.D., and Bhinder, G. Two years experience with the Copper-200 in India. Contraception 10: 337-349 (1974).
8.
Tejuja S., Choudhury, S. D., Nalhotra, U.h Saxena, N. C. Clinical trial with the Copper-7 intrauterinedevice. One year experience in India. Contraception10: 351-360 (1964).
9.
Akinla, O., Luukkainen, T., and Timonen, Ii. Important factors in the use effectivenessof the Copper-T-200 IUD. Contraception 12: 697-707 (1973).
10.
11.
12.
122
hkinla, 0. Bleeding endtheuse effectivenessof the CopperT-200 IUD. A Brief Review. Nigerian Medical Journal 7: 71-76 (1977). Recommended procedures for the Tietze, C., Lewitt, S. statistical evaluation of intrauterinecontraception. Studies in Family Planning 4: 33-42 (1973). Tatum, H.J. The endouterineCopper-T procedure manual. Bio-medical Division,ThePopulation Council (1971).
AUGUST
1980 VOL. 22 NO. 2
MURIELA. OYEDIRAN,I.B.B.S.,MPH Department of Community Health College of Medicine University of Lagos, Nigeria
OLADELE AKINLA, F.R.C.S.,M.R.C.O.G. Department of Obstetrics and Gynaecology College of Medicine University of Lagos, Nigeria
ABSTRACT
A non-randomisedstudy was performed to compare the useeffectivenessof the Copper-T-200and Nova-T intrauterinedevices. It was found that generally, results compared favourably with other world-wide studies. No accidental pregnancieswere experienced and no significant difference was found between the expulsion rate of the Nova-T (5.0) and that of the Copper-T-200 (6.5) and the removal rates for bleeding and pain, which were 1.5 and 3.8, respeotively. The continuationrate for the Nova-T was 91.3 compared with 88.2 for the Copper-T. The total experiencewas based on 815 woman-monthsof use,
Accepted for publication July 15, 1980
AUGUST
1980VOL.22N0.2
115
CONTRACEPTION INTRODUCTION The Copper-T-200 intrauterine device extensively in many countries (1,2,3,5,6,7) use throughout the world.
(IUD) has been tested and is now in general
However Copper IUDs have not been used extensively in Nigeria because the Lippes loop, first introduced to the country in 1964
by its Family Planning Council, has been the most popularly used and most easily available IUD up until now. In view of the fact that several studies have shown the advantages of the Copper-T over the Lippes loop, with regard to the continuation rate, expulsion rate, accidental pregnancy rate, and rate of removals for bleeding and pain (4,6,9), it was decided to test the CU-T-200 on patients attending the Family Planning Clinic of the Department of Community Health of the College of Medicine, University of Lagos. At the same time, a new copper device called the Nova-T had recently been introduced in Finland end one of us (O.A.) brought some to Lagos. It was decided to compare these two forms of the copper device in the same clinic population. The study was performed with a view to establishingwhether there were any variations in results compared with reported experiencesfrom other countries.
METHODS _.-One-hundred-and-thirty-two women attending the Family Planning Clinic, and who had choSeA the IUD as their method of contraception, were included in the non-randomisedtrial. The insertions of the Copper-T-2C0 and the Nova-T were performed initially by two physicians (O.A. and a Senior House Officer), then by one physician only (M.A.O.). The insertionswere performed during a menstrual period or within one or two days post-menstrually. Sixty-five women had the Nova-T inserted and 67 had the Copper-T-200. The principal differences between the Nova-T and the Copper-T-200 (Fig. 1 and 2) are as follows: The junction of the horizontal and vertical arms in the Nova-T is curved enabling the Nova-T to retain its memory more easily after insertion; perforation or penetration of the cervical tissue is eliminatedby increasing the surface area of the Nova-T at the end of the vertical arm which is formed in a loop; the horizontal arms of the Nova-T are directed upwards when loaded into the inserter, while the horizontal srms of the Copper-T-200 are directed downwards, which leads to a variation in insertion technique such that when the Copper-T device and inserter tube are inserted into the uterine cavity, retraction of the inserter tube releases the arms of the device aAd also places it at the fundus of the uterus (12), whereas with the Nova-T, retraction of the inserter tube releases the arms of the deviceonly, it then requires to be positioned at the fundus of the uterus by the extra procedure of pushing it up into position with the inserter techniques and methods of withdrawal of tube - the pre-insertion the inserter tube and plunger are,however,the same for both devices;
116
AUGUST
1980 VOL. 22 NO. 2
CONTRACEPTION
Fig.
1
,;,,;~~--.‘~..2f,(1 .J
Fig. 2 Nnvd-T
AUGUST
1980 VOL. 22 NO. 2
117
CONTRACEPTION
the rounded hemispheres of the Nova-T also cover the edges of the inserter so that a rounded sphere is presented when insertion occurs and this gives an easier and less painful insertion - there is also less risk of penetration of uterine tissue because of the beaded ends of the horisontal arms; and ?.astly,by incorporating a silver core in the centre of the copper wire used in the Nova-T, it is hoped to extend its life. The life table method described by Tietre & Lewitt (11) was used in the analysis of the data.
RBSULTS Age Distribution: Table I Age Distributionof the Women in the Studg
NOVA-T
Cu-T
Total
P value
.--7q-7
Age
No.
20.24
3
4.6
8
6.1
0.25
25-29
12
18.5
28
21.2
0.66
30-34
17
26.1
47
35.6
0.24
35 +
33
50.8
49
37.1
0.12
65 t-k
100.0
%
I
67 I loo.0
Worn Table I it is seen that the age distributionbetween the two groups of wmen using either the Nova-T or Copper-T-EC0did not vary significantly. No woman under the age of 20 was fitted with an IUD, and over 70% of the patients who were fitted were over 30 years in both groups. The lowest number of insertions was in the 20 - 24 year group for both Nova-T and Copper-T-200.
118
AUGUST
1980 VOL. 22 NO. 2
CONTRACEPTION Parity: Table II Distributionof Parity of the Women Using the Nova-T & Cu-T-200 IUDs Cu-T
Nova-T Parity
No.
Total
No.
5
I1
No.
0
1.5
3
1
1.5
3
2
16.4
16
80.6
110
3+
k
2.3
2.3
12.1
83.3
:
65
100.0
I
I
67
I 100.0
I
132
I
1 loo.O(
The majority of women (over 8% in both groups)had had three or more live births. Only 6.s of the women who had the Nova-T and 3% of those using the Copper-T-200 had fewer than two children (Table II). TerminationRates: Table III --Ret Cumulative TerminationRates per 100 Yoren at 12 Months (with 9%
lower and uooer confidence limits)
T
Nova-T Type of Termination
Rate
LL
UL
1
Cu-T
Rate
LL
UL
pregnancy Expulsion
5.0
1.1
14.5
6.5
1.8
16.6
Bleeding/Pain
1.5
0.4
8.4
3.8
1.0
9.7
Other Personal
2.2
0.3
7.9
1.5
0.2
5.2
Total Terminations
8.7
1.8
30.8
11.8
3.0
31.7
91.3
98.2
69.2
88.2
97.0
68.3
Other Medical Planning Pregnancy
Total Continuations
AUGUST
1980VOL.22N0.2
119
CONTRACEPTION In this series althougil the total 815 women months of use, no pregnancies no removals for “other medical” reasons In the light of the high (Table III). the patients, 8W0 of whom had 3 or more surprising.
experience was only for occurred. There were also or for “planning pregnancy” parity oi the majority of live births, this is not
The expulsion rate for Nova-T was 5.0 compared to 6.5 with the Similarly all other Cu-T, but this difference was not significant. rates were lower for the Nova-T, but more so for bleeaing / pain where only 1.5 removals occurred per 100 women using the Nova-T The continuation rate for the campared with 3.8 for the Cu-T. Nova-T was higher than that for the Cu-T, being 91.3 compareu with However, none of these differences were found to be signi88.2. ficant. DlSCUSSlCn --Pregnancy: No accidental pregnancies were recorded for the 12 months of use for either the Nova-T or the Copper-T-200. It was therefore not possible to come to any conclusion regarding a lower pregnancy In the rate for the Nova-T as found by Luukkainen et al. (2). same study, they also found that the pragnzyxte for the Nova-T was lower in every age and parity group.
Timonen and Luukkainen in another study (3) also showed that the pregnancy rate for the Copper-T-200 declined with increasing parity, while Lewitt (4) observed that accidental pregnancies tended In the light of the above facts, the absence to decline with age. of accidental pregnancies in our study might be related to the fact that 83% of the total clinic population had a parity of over three children and 7% were over the age of 30 years. &ulsion: --._The difference in the expulsion rates in this study, of 5.0 for the Nova-T and 6.5 for the Copper-T-200, was not significant. The comparative study by Luukkainen et al. (I) recorded an expulsion rate of 5.8 for the Nova-T compared with.8 for the Copper-T-EOC but this result was also not statistically significant. The expulsion rate of Copper-T-200 in the Lagos study (6.5) compared favourably with the 7.0 obtained by Tejuja et al. in India (8). Bowever, Pulido and Heasham in Colombia (6) experienced a high expulsion rate of 8.2. The Colombian study however had a clinic population in which only 2%: of the women were over 30 years of age compared with 73% in Lagos. ParitS also varied, with 44% of the Colombian women having more than 3 children, compared with 83$ of the Lagos women. The higher age range and parity of the Lagos women associated with a lower expulsion rate tends to support observations by other researchers that increasing age and parity were associated with declining expulsion rates (4, 2).
120
AUGUST
1980 VOL. 22 NO. 2
CONTRACEPTION Bleeding
ani Pain:
The main medical reason for removal of the Copper-T-200 in a study by Timonen and Luukkainen (3) was for bleeding and/or pain, removals for and this was found to be closely reiated with age; this reason being highest in the age-group under 25. The under 23 age-group was unfortunately under-represented in the Lagos study. with However, the rate of 3.8 in this study compared favourably their rate of 4.0 for all acceptors. In another study by the same authors (l), however, the removal rates for pain and bleeding were high, being 13.9 for the CopperThe reasons for these large values T-200 and 12.3 for the Nova-T. were thought to be due to less well-trained personnel performing insertions, and removals being carried out for the slightest indication. Timonen and Luukkainen (3) recorded that women under 2.5 years of age had a high risk for developing infection regardless of parity, and that removals for other medical reasons were greater in this They also showed that with the Copper-T-200, the removal age group. rate for planning pregnancies showed a high negative correlation These findings are consistent with our findings with age and parity. in which the under 25 age-group because in our clinic population, was under-represented and only formed 6.s of the total clinic population, no removals were experienced for infection, other medical reasons or for planning pregnancies. The continuation rates in the Lagos study of 91.3 for the Nova-T and 88.2 for the Copper-T compared favourably with 72.6 and ::;‘? for the Nova-T and Cu-T, respectively, in Luukkainen’s study Akinla et al. (9) stated that the highest continuation rates in iheir study were found when insertions were done during or This is the policy in the Clinic immediately after menstruation. in which the present research was done, and all insertions were done in the first week of the menstrual cycle. The differences already mentioned earlier, with regard to lower rates of removals for bleeding and pain in the Lagos study compared with the rates in Europe (l), are of significance. Removals for pain and bleeding have been one of the most frequent drawbacks in the use of the Lippes loop in developing countries (10). One of the problems caused by the excessive bleeding is that a potentially anaemic state may becme overt leading to a deterioration in maternal health and well-being. In view of the fact that both the Nova-T and the Copper-T-200 have produced results that are comparable with, and in saae cases better than those obtained in Europe, the addition of the copper IUDs to the armsmentarium of the family planner can only but herald a more favourable attitude to the use of intrauterine devices in developing countries.
1.
Luukkainen, T., Nielsen, N.C., Nygren, Ii. G., Pyorala, T., and Kosonen, A. Randomised comparison of clinical performance of two copper-releasing IUDs, Nova-T and Copper-T-200 in Denmark, Finland and Sweden. Contraception 19: l-9 (1979).
AUGUST
1980 VOL. 22 NO. 2
121
CONTRACEPTION
2.
Luukkainen, T., Nielsen, N. C., Nygren. K. G., Pyorala, T. Combined and national experience of postand Allonen, h. menstrual IUD insertions of Nova-T and Copper-T in a randomised study. Contraception198 11-20 (1979).
3.
The use effectivenessof Timonen, H., and Luukkainen,T. the Copper-T-200 in a simulated field trial. Contraception 9: 1-13 (1974).
4.
Two years Experience with the Copper-T: A Research Lewit, S. Report. Studies in Family Planning 4: 171-172 (1973).
5.
The effectivenessof the Copper-T intrauterine Silvin, I. device. A CoilaborativeStudy in Five Countries. Studies in Family Planning 4: 162-170 (1973).
6.
Tvo-year result of a clinical Pulido M., and Measham, A. R. study of the T-Cu-200 IUD in Colombia. Studies in Family Planning 5: 221-223 (1974).
7.
Tejuja, S., Savena, N.C., Malhotra, LT.,Choudbury, S.D., and Bhinder, G. Two years experience with the Copper-200 in India. Contraception 10: 337-349 (1974).
8.
Tejuja S., Choudhury, S. D., Nalhotra, U.h Saxena, N. C. Clinical trial with the Copper-7 intrauterinedevice. One year experience in India. Contraception10: 351-360 (1964).
9.
Akinla, O., Luukkainen, T., and Timonen, Ii. Important factors in the use effectivenessof the Copper-T-200 IUD. Contraception 12: 697-707 (1973).
10.
11.
12.
122
hkinla, 0. Bleeding endtheuse effectivenessof the CopperT-200 IUD. A Brief Review. Nigerian Medical Journal 7: 71-76 (1977). Recommended procedures for the Tietze, C., Lewitt, S. statistical evaluation of intrauterinecontraception. Studies in Family Planning 4: 33-42 (1973). Tatum, H.J. The endouterineCopper-T procedure manual. Bio-medical Division,ThePopulation Council (1971).
AUGUST
1980 VOL. 22 NO. 2