Int J Gynaecol Obstet 15: 88-92, 1977
Alternatives to Female Sterilization S. S. Ratnam, Mary Rauff, and S. C. Chew Department of Obstetrics and Gynaecology, University of Singapore, Kandang Kerbau Hospital, Singapore, Republic of Singapore
ABSTRACT Ratnam, S. S., Rauff, M. and Chew, S. C. (Dept. of Obstetrics and Gynaecology, University of Singapore, Kandang Kerbau Hospital, Singapore). Alternatives to female sterilization. Int J Gynaecol Obstet 15: 88-92, 1977 With national policies aimed at reaching zero population growth in the shortest possible time, many countries have introduced restrictive legislation and disincentive programs in an attempt to decrease family size norms to 2 or 3 children. As a result, younger women of lower parity are being sterilized, with consequences that will be seen in the years to come. Although female sterilization is usually associated with minimal complications and side effects and is highly effective without continuing motivation or promotion, it has the disadvantage of causing permanent, essentially irreversible sterility. Therefore, it will not be readily acceptable to a large portion of the population. For many women, alternatives must be sought. Reversible methods of female or male sterilization, longacting systemic contraceptives, longacting implants, and immunization against implantation or sperm antigens are potential alternatives, but all are still in experimental stages of development. Intrauterine devices and injectables are the 2 most effective alternatives now available. The use of intrauterine devices with abortion as a backup in case of contraceptive failure ranks high as an alternative to female sterilization.
INTRODUCTION Female sterilization is an effective and safe method of terminating fertility. However, for various reasons, alternatives to female sterilization must be considered. First, sterilization is intended to be permanent, despite ostensibly reversible methods such as ovariopexy and salpingopexy. In countries such as Singapore where sterilization has been made available without restrictions on age and parity, progressively younger, less parous women have accepted the method, despite the possibility that through unforeseen vicissitudes of life they may have cause later to want to restore their fertility. To avoid such cases, alternatives to sterilization should be considered for young women of low parity. Second, safe, effective female sterilization can be provided only by skilled surgeons in well-equipped facilities. Thus, the method is not available to many women, particularly those in rural areas of developing countries. Thus paper was presented at the IX World Congress of Fertility and Sterility, Miami Beach, Florida, USA, April 12-16, 1977. Int J Gynaecol Obstet 15
The chief attributes of female sterilization are reliability and method-dependency. The method cannot fail owing to patient factors. Hence, in considering suitable alternatives to female sterilization, one must look to methods which also share these important attributes. Oral contraception is a poor substitute since this method is totally dependent on the patient's ability to use it properly. This factor is especially important in lesser developed regions where patients find the pill regimen complicated and large numbers of failures occur. Injectable progestogens and intrauterine devices (IUDs) are more acceptable alternatives. Vasectomy is also an alternative, and various immunologic approaches for both males and females are being investigated. ALTERNATIVES TO FEMALE STERILIZATION Male sterilization Vasectomy is a good alternative to female sterilization in some situations. Although it is also a permanent method with some of the same disadvantages as female sterilization, it is a simpler procedure, often requiring less skilled personnel and less sophisticated equipment and facilities. From the standpoint of population dynamics, a single man can potentially father more children than a single woman can produce in her lifetime; hence, vasectomy is theoretically more cost-effective. Yet the method has not gained the expected acceptance in Singapore, and in many countries it has not been introduced yet or, if introduced, has not gained momentum. In Singapore, male sterilization was introduced more than 5 years ago, but the ratio of male to female sterilization was only 1:70 in 1976. Intrauterine devices The mode of action of intrauterine devices remains an enigma. They do not prevent fertilization nor do they suppress ovulation or the function of the corpus luteum. They do cause inflammatory changes in the endometrium and phagocytosis of spermatozoa by macrophages. They do not appear to affect levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol and progesterone, but
Alternatives
menstruation starts an average of 2 days earlier than normal. Hence IUDs may cause an "asynchronism" that may persist for a year or more. Implantation of the fertilized ovum is interfered with. With the copper and copper-zinc devices, biochemical changes occur in the uterine secretion—alkaline phosphatase levels increase while glucose levels decrease. Carbonic anhydrase reaction may be inhibited leading to missed implantation. The metal is also toxic to the spermatozoa and inhibits sperm motility. The copper ions interfere with cellular DNA in the endometrium and with the normal rate of endogenous estrogen uptake by the uterine mucosa. Whatever its mode of action, the IUD offers many advantages. It offers contraceptive protection that is inexpensive, long-lasting, effective, and reversible; and it does not interfere with coitus. It requires 1 decision by the patient and a single insertion procedure. However, side effects and complications with this method have proved to be significant. They include menstrual upset and pain, infection, leukorrhea, ectopic pregnancy, perforation, and expulsion. Therefore, in contrast to female sterilization, IUD use requires continuing follow-up care. Experience with the Lippes Loop in Singapore in 1966 resulted in the highest perforation rate ever recorded. Many insertions were performed in womp" who were 4 to 8 weeks postpartum. Risk of perforation can be reduced by performing insertions during the immediate postpartum period or delaying to 8 weeks after delivery. Occasionally, it may be difficult to ascertain whether perforation has occurred, but ultrasound B scanning may be used to provide a quick noninvasive check on the position of the device if there is any reason to suspect uterine perforation. X-rays are not required and may in fact be uninformative because the uterine outline is not seen. Bleeding—increased and/or prolonged m e n s e s remains a problem with all IUDs although it appears to be a little less with copper devices. The exact cause for the bleeding is not known, but increased fibrinolysis and prostaglandin activity have been implicated. This side effect is a major problem in communities where anemia is prevalent. While some preliminary work on antifibrinolytic agents appears promising, the rationale of prolonged therapy may not be sound. Infection is also probably increased in IUD users, although statistical "proof may not be easy to establish. When the infection occurs within a month of the insertion, the insertion is held liable. On the other hand, many get an infection after a longer period, and in these cases infection is probably due to sexual intercourse rather than to IUD use. One much publicized series included 13 deaths from septic abortion among women using Dalkon Shields at the time they became pregnant. The infection was later
to sterilization
89
attributed to the polyfilament tails on the devices. The manufacturers withdrew the device from the market. There is also an increased risk of ectopic pregnancies among women using IUDs, but the risk seems to diminish over time as a woman continues to wear the device. Intrauterine implantation is estimated to be reduced by 99.5%; tubal pregnancies, by 90.0%; and ovarian ones, not at all. With intrauterine implantation, 50% end in spontaneous abortion, 3 times the abortion rate of women using other contraceptive methods. When a pregnancy occurs, the overall risk of an ectopic pregnancy is estimated to be 10-20%. Expulsion has occurred with all devices, and attempts have been made to combat this problem by changes in the shape or the size of the device so that it more closely fits the uterine cavity. Some form of bending is required to fit copper devices into the inserter, and it is recommended that these devices be inserted as soon as possible after the arm has been bent to keep the devices from "losing their memory". In our experience, the Copper-7 has the highest expulsion rate. Insertions performed during the immediate postpartum are also associated with higher expulsion rates. Presently, our unit is conducting an ongoing study on a number of second generation devices: Copper-7, Copper 220-T, Multiload 220, Multiload 375, Anderson Leaf and Dalkon Shield (insertions of which are no longer being done). The net cumulative event rates per 100 women as of November 30, 1976 with some of the devices are shown in Table I. Alth^'gh we have less experience with the Multiload than with the other devices, we feel that it will prove superior in many respects. A progestogen-releasing device (Alza-T), with a reservoir in the upright limb containing progestogen which diffuses through the device at the steady rate of 65 Mg per day, also shows promise. Cooper et al. have reported pregnancy rates almost as low as the rates for oral contraceptives, and the device has the additional advantage of alleviating the bleeding problems so prevalent with IUD use. Injectables Injectables also have decisive advantages as an alternative method to female sterilization. They are method-dependent and may be administered by paramedical personnel once the initial selection has been made. The compounds used include medroxyprogesterone acetate (MPA), chlormadinone acetate (now withdrawn), and norethisterone enanthate. The one used most extensively is MPA, and it may be given at 3-month or 6-month intervals, depending on the dose selected. Norethisterone enanthate is administered at 12-week intervals in doses of 200 mg. These compounds have prolonged antiestrogenic Int J Gynaecol Obstet 15
90
S. S. Ratnam et al.
and fertility-inhibiting actions by temporarily inhibiting the hypothalamic-pituitary-gonadal function and interfering with the release of LH at the midcycle. The efficacy of norethisterone enanthate has not been fully evaluated. A failure rate of 5.6 per 100 woman-years has been reported with a 200 mg dose. In 1 series, nearly all women stopping the regimen resumed normal menstruation within 2 to 4 months of the last injection. Injections of MPA every 3 months were found to have a cumulative pregnancy rate of 0.8 per 100 woman-years after 4 years of use. The equivalent rate for injections repeated every 6 months over the same period was 4.9 per 100 woman-years. Hence, it would appear that this method has better contraceptive efficacy than the IUD. With higher doses of 500 mg and 1 g repeated at 6-month intervals, no pregnancies had occurred after 48 months. Unfortunately, injectables are also associated with side effects which have limited their acceptance. The usual effects of progestogens on fluid metabolism have led to increased headaches, dizziness, nervousness, irritability, and abdominal discomfort. More serious side effects have also occurred. These include (1) slow recovery of fertility, (2) irregular menstrual cycles and amenorrhea, (3) congenital malformation among infants conceived by women receiving injectables, and (4) increased incidence of breast tumors and metabolic changes. About 80% of the women who discontinue injectables become pregnant within 15 months of the last injection. The cumulative pregnancy rate 18 months after the last injection of MPA in a WHO series appeared to be similar to the corresponding rate observed after removal of an IUD. The slow recovery of fertility is usually associated with amenorrhea or
long cycles of anovulation. The use of fertility drugs such as clomiphene, cyclopherid and/or gonadotrophins may hasten ovulation where this is urgently needed. Whether MPA has any permanent effects on fertility in some women is unknown. The heavy bleeding often associated with IUD use is seldom a problem with women on progestogens. However, progressively scantier periods, "spotting", and amenorrhea are common. Episodes of spotting are followed by periods of amenorrhea which become more frequent with prolonged use. Education of the patient on the natural course to be expected is important to ensure continuation. However, in spite of careful explanation and patient selection, in a Singapore study of 1234 muciparous patients receiving Depo-Provera injections, 52% had discontinued use after 18 months. The primary reasons for discontinuing were irregular spotting and amenorrhea. This high dropout rate occurred in spite of the fact that all patients were para 2 and above and had been forewarned of the various complications, including menstrual irregularities. In a second series of 310 cases, 44% had completed their families while the rest wanted to space their children. The possible side effects were explained to the patients. The continuation rate after 6 months was 50%; after 12 months, it was 25%. The high dropout rate was attributed to menstrual disturbances, although 34% stopped for "unknown reasons". In Singapore, women appear to tolerate amenorrhea better than irregular bleeding provided reassurance is given. To induce withdrawal bleeding, oral estrogens have been recommended for 7 to 10 days of each calendar month. This treatment has been used with some success in Thailand, where it was based on the lunar calendar;
Table I. Net cumulative event rates per 100 women, by levice as of November 30, 1976 after 12 months of use
Event
Dalkon Shield
Gravigard
Alternatives to Female Sterilization S. S. Ratnam, Mary Rauff, and S. C. Chew Department of Obstetrics and Gynaecology, University of Singapore, Kandang Kerbau Hospital, Singapore, Republic of Singapore
ABSTRACT Ratnam, S. S., Rauff, M. and Chew, S. C. (Dept. of Obstetrics and Gynaecology, University of Singapore, Kandang Kerbau Hospital, Singapore). Alternatives to female sterilization. Int J Gynaecol Obstet 15: 88-92, 1977 With national policies aimed at reaching zero population growth in the shortest possible time, many countries have introduced restrictive legislation and disincentive programs in an attempt to decrease family size norms to 2 or 3 children. As a result, younger women of lower parity are being sterilized, with consequences that will be seen in the years to come. Although female sterilization is usually associated with minimal complications and side effects and is highly effective without continuing motivation or promotion, it has the disadvantage of causing permanent, essentially irreversible sterility. Therefore, it will not be readily acceptable to a large portion of the population. For many women, alternatives must be sought. Reversible methods of female or male sterilization, longacting systemic contraceptives, longacting implants, and immunization against implantation or sperm antigens are potential alternatives, but all are still in experimental stages of development. Intrauterine devices and injectables are the 2 most effective alternatives now available. The use of intrauterine devices with abortion as a backup in case of contraceptive failure ranks high as an alternative to female sterilization.
INTRODUCTION Female sterilization is an effective and safe method of terminating fertility. However, for various reasons, alternatives to female sterilization must be considered. First, sterilization is intended to be permanent, despite ostensibly reversible methods such as ovariopexy and salpingopexy. In countries such as Singapore where sterilization has been made available without restrictions on age and parity, progressively younger, less parous women have accepted the method, despite the possibility that through unforeseen vicissitudes of life they may have cause later to want to restore their fertility. To avoid such cases, alternatives to sterilization should be considered for young women of low parity. Second, safe, effective female sterilization can be provided only by skilled surgeons in well-equipped facilities. Thus, the method is not available to many women, particularly those in rural areas of developing countries. Thus paper was presented at the IX World Congress of Fertility and Sterility, Miami Beach, Florida, USA, April 12-16, 1977. Int J Gynaecol Obstet 15
The chief attributes of female sterilization are reliability and method-dependency. The method cannot fail owing to patient factors. Hence, in considering suitable alternatives to female sterilization, one must look to methods which also share these important attributes. Oral contraception is a poor substitute since this method is totally dependent on the patient's ability to use it properly. This factor is especially important in lesser developed regions where patients find the pill regimen complicated and large numbers of failures occur. Injectable progestogens and intrauterine devices (IUDs) are more acceptable alternatives. Vasectomy is also an alternative, and various immunologic approaches for both males and females are being investigated. ALTERNATIVES TO FEMALE STERILIZATION Male sterilization Vasectomy is a good alternative to female sterilization in some situations. Although it is also a permanent method with some of the same disadvantages as female sterilization, it is a simpler procedure, often requiring less skilled personnel and less sophisticated equipment and facilities. From the standpoint of population dynamics, a single man can potentially father more children than a single woman can produce in her lifetime; hence, vasectomy is theoretically more cost-effective. Yet the method has not gained the expected acceptance in Singapore, and in many countries it has not been introduced yet or, if introduced, has not gained momentum. In Singapore, male sterilization was introduced more than 5 years ago, but the ratio of male to female sterilization was only 1:70 in 1976. Intrauterine devices The mode of action of intrauterine devices remains an enigma. They do not prevent fertilization nor do they suppress ovulation or the function of the corpus luteum. They do cause inflammatory changes in the endometrium and phagocytosis of spermatozoa by macrophages. They do not appear to affect levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol and progesterone, but
Alternatives
menstruation starts an average of 2 days earlier than normal. Hence IUDs may cause an "asynchronism" that may persist for a year or more. Implantation of the fertilized ovum is interfered with. With the copper and copper-zinc devices, biochemical changes occur in the uterine secretion—alkaline phosphatase levels increase while glucose levels decrease. Carbonic anhydrase reaction may be inhibited leading to missed implantation. The metal is also toxic to the spermatozoa and inhibits sperm motility. The copper ions interfere with cellular DNA in the endometrium and with the normal rate of endogenous estrogen uptake by the uterine mucosa. Whatever its mode of action, the IUD offers many advantages. It offers contraceptive protection that is inexpensive, long-lasting, effective, and reversible; and it does not interfere with coitus. It requires 1 decision by the patient and a single insertion procedure. However, side effects and complications with this method have proved to be significant. They include menstrual upset and pain, infection, leukorrhea, ectopic pregnancy, perforation, and expulsion. Therefore, in contrast to female sterilization, IUD use requires continuing follow-up care. Experience with the Lippes Loop in Singapore in 1966 resulted in the highest perforation rate ever recorded. Many insertions were performed in womp" who were 4 to 8 weeks postpartum. Risk of perforation can be reduced by performing insertions during the immediate postpartum period or delaying to 8 weeks after delivery. Occasionally, it may be difficult to ascertain whether perforation has occurred, but ultrasound B scanning may be used to provide a quick noninvasive check on the position of the device if there is any reason to suspect uterine perforation. X-rays are not required and may in fact be uninformative because the uterine outline is not seen. Bleeding—increased and/or prolonged m e n s e s remains a problem with all IUDs although it appears to be a little less with copper devices. The exact cause for the bleeding is not known, but increased fibrinolysis and prostaglandin activity have been implicated. This side effect is a major problem in communities where anemia is prevalent. While some preliminary work on antifibrinolytic agents appears promising, the rationale of prolonged therapy may not be sound. Infection is also probably increased in IUD users, although statistical "proof may not be easy to establish. When the infection occurs within a month of the insertion, the insertion is held liable. On the other hand, many get an infection after a longer period, and in these cases infection is probably due to sexual intercourse rather than to IUD use. One much publicized series included 13 deaths from septic abortion among women using Dalkon Shields at the time they became pregnant. The infection was later
to sterilization
89
attributed to the polyfilament tails on the devices. The manufacturers withdrew the device from the market. There is also an increased risk of ectopic pregnancies among women using IUDs, but the risk seems to diminish over time as a woman continues to wear the device. Intrauterine implantation is estimated to be reduced by 99.5%; tubal pregnancies, by 90.0%; and ovarian ones, not at all. With intrauterine implantation, 50% end in spontaneous abortion, 3 times the abortion rate of women using other contraceptive methods. When a pregnancy occurs, the overall risk of an ectopic pregnancy is estimated to be 10-20%. Expulsion has occurred with all devices, and attempts have been made to combat this problem by changes in the shape or the size of the device so that it more closely fits the uterine cavity. Some form of bending is required to fit copper devices into the inserter, and it is recommended that these devices be inserted as soon as possible after the arm has been bent to keep the devices from "losing their memory". In our experience, the Copper-7 has the highest expulsion rate. Insertions performed during the immediate postpartum are also associated with higher expulsion rates. Presently, our unit is conducting an ongoing study on a number of second generation devices: Copper-7, Copper 220-T, Multiload 220, Multiload 375, Anderson Leaf and Dalkon Shield (insertions of which are no longer being done). The net cumulative event rates per 100 women as of November 30, 1976 with some of the devices are shown in Table I. Alth^'gh we have less experience with the Multiload than with the other devices, we feel that it will prove superior in many respects. A progestogen-releasing device (Alza-T), with a reservoir in the upright limb containing progestogen which diffuses through the device at the steady rate of 65 Mg per day, also shows promise. Cooper et al. have reported pregnancy rates almost as low as the rates for oral contraceptives, and the device has the additional advantage of alleviating the bleeding problems so prevalent with IUD use. Injectables Injectables also have decisive advantages as an alternative method to female sterilization. They are method-dependent and may be administered by paramedical personnel once the initial selection has been made. The compounds used include medroxyprogesterone acetate (MPA), chlormadinone acetate (now withdrawn), and norethisterone enanthate. The one used most extensively is MPA, and it may be given at 3-month or 6-month intervals, depending on the dose selected. Norethisterone enanthate is administered at 12-week intervals in doses of 200 mg. These compounds have prolonged antiestrogenic Int J Gynaecol Obstet 15
90
S. S. Ratnam et al.
and fertility-inhibiting actions by temporarily inhibiting the hypothalamic-pituitary-gonadal function and interfering with the release of LH at the midcycle. The efficacy of norethisterone enanthate has not been fully evaluated. A failure rate of 5.6 per 100 woman-years has been reported with a 200 mg dose. In 1 series, nearly all women stopping the regimen resumed normal menstruation within 2 to 4 months of the last injection. Injections of MPA every 3 months were found to have a cumulative pregnancy rate of 0.8 per 100 woman-years after 4 years of use. The equivalent rate for injections repeated every 6 months over the same period was 4.9 per 100 woman-years. Hence, it would appear that this method has better contraceptive efficacy than the IUD. With higher doses of 500 mg and 1 g repeated at 6-month intervals, no pregnancies had occurred after 48 months. Unfortunately, injectables are also associated with side effects which have limited their acceptance. The usual effects of progestogens on fluid metabolism have led to increased headaches, dizziness, nervousness, irritability, and abdominal discomfort. More serious side effects have also occurred. These include (1) slow recovery of fertility, (2) irregular menstrual cycles and amenorrhea, (3) congenital malformation among infants conceived by women receiving injectables, and (4) increased incidence of breast tumors and metabolic changes. About 80% of the women who discontinue injectables become pregnant within 15 months of the last injection. The cumulative pregnancy rate 18 months after the last injection of MPA in a WHO series appeared to be similar to the corresponding rate observed after removal of an IUD. The slow recovery of fertility is usually associated with amenorrhea or
long cycles of anovulation. The use of fertility drugs such as clomiphene, cyclopherid and/or gonadotrophins may hasten ovulation where this is urgently needed. Whether MPA has any permanent effects on fertility in some women is unknown. The heavy bleeding often associated with IUD use is seldom a problem with women on progestogens. However, progressively scantier periods, "spotting", and amenorrhea are common. Episodes of spotting are followed by periods of amenorrhea which become more frequent with prolonged use. Education of the patient on the natural course to be expected is important to ensure continuation. However, in spite of careful explanation and patient selection, in a Singapore study of 1234 muciparous patients receiving Depo-Provera injections, 52% had discontinued use after 18 months. The primary reasons for discontinuing were irregular spotting and amenorrhea. This high dropout rate occurred in spite of the fact that all patients were para 2 and above and had been forewarned of the various complications, including menstrual irregularities. In a second series of 310 cases, 44% had completed their families while the rest wanted to space their children. The possible side effects were explained to the patients. The continuation rate after 6 months was 50%; after 12 months, it was 25%. The high dropout rate was attributed to menstrual disturbances, although 34% stopped for "unknown reasons". In Singapore, women appear to tolerate amenorrhea better than irregular bleeding provided reassurance is given. To induce withdrawal bleeding, oral estrogens have been recommended for 7 to 10 days of each calendar month. This treatment has been used with some success in Thailand, where it was based on the lunar calendar;
Table I. Net cumulative event rates per 100 women, by levice as of November 30, 1976 after 12 months of use
Event
Dalkon Shield
Gravigard
