Pakistan J. Med. Res.

Vol. 42 No.4, 2003

Female sterilization and its effects on women  health


Ghazala Ashfaq, Faizullah Kakar, Maqbool Ahmed.

National Institute Of Health, Islambad, Epidemiologist, WHO Islamabad, Biology Department Quaid e Azam University, Islamabad




Background: Female sterilization (tubal ligation) is the method of choice for most of the women world over. Among the Current users of contraceptives in Pakistan the same method is at top.Female sterilization has provided a permanent means of controlling unwanted pregnancies, yet it has not been free of both immediate and long-term reproductive health complications for women opting for the procedure. The postligation effects have been linked to preexisting conditions, age, method of ligation by the researchers. Pakistani women have a unique characteristic in terms of low hormonal contraceptive use, high parity and other social and cultural factors.


Objective: The objective of the study was to find long-term effects of female sterilization on health of women at least 2 years after ligation.


Methodology: A descriptive,community-based study was conducted by visiting women in their homes in communities surrounding the area of Islamabad and Rawalpindi. Women who had undergone tubal sterilization were interviewed.


Result: The data collected has revealed the ligated women reporting more for health and two fold greater Gynecological disorders  as compared to control group.


Conclusion: Long term follow up services are required to be strengthened.


Key words: Female sterilization, Gynecological disorder, Contraceptive, Pakistan




Contraception in general and sterilization in particular have far reaching significance for family planning and population control. This has been and continues to be of paramount importance for developing countries. Since the major focus in family planning programs has traditionally been on female contraception, serious concern relates to women’s reproductive health and the kind of service available to them for alleviating their problems, both in individual terms and social context. While temporary contraceptive methods in the female have been prevalent for quite some time, female sterilization as an irreversible means of contraception has gained popularity over the last few decades, especially in the industrialized countries. Tubal ligation can be carried out either immediately after delivery, i.e., as postpartum sterilization or about 40 days postpartum when it is called interval sterilization1.


In the United States of America, almost 72% of combined male and female sterilizations consisted of female tubal sterilization during the period 1998-20002, 3 Globally, over 190 million couples opted for sterilization by the year 20003, most of which have been interval sterilizations. Tubal ligation is the most widely used contraceptive method the world over. According to available statistics, 40% of the couples of 40 years of age prefer tubal ligation as the method of choice.


Use of contraceptives by Pakistani women has shown an increase from 9% in 1984 to 24% by 19974, and 30 % by 20025. One fourth of the current users have adopted female sterilization.


Whereas tubal sterilization has provided a permanent means of controlling unwanted pregnancies, it has not been free of both immediate and long-term reproductive health complications for women opting for the procedure.


Besides lack of complete protection from further pregnancies, women also tend to complain of complications that are collectively known as “post tubal ligation syndrome”6. The aggregate symptoms that characterize this syndrome are pelvic pain, increased menstrual flow, cramps, altered hormonal profile, change in menstrual cycle and luteal phase defects of the reproductive cycle, general gynecological problems, change in sexual behavior and in mental health 3,6-11.  One of the consequences of tubal ligation in some cases is precipitation of menopause. Disruption of uteroovarian blood supply, as may happen in cases of cauterization, seems to be one of the most serious causes of post ligation abnormalities 6,12.


In view of the reported consequences of ligation procedure, the present investigation was planned to determine the effects of tubal ligation and risk of disruption of gynecological health of women on a cross section of women residing in the Islamabad-Rawalpindi area of Pakistan. A major compulsion for conducting the present investigation was the unique socioeconomic background of women in Pakistan with low literacy rate young age marriages, high parity, overall low contraception practice and prevalence of sterilization as the method of choice. The objective of the study was to find long-term effects of ligation on health of women at least 2 years after ligation.




Study population and investigative design

The subjects for the study were recruited from the resident community of Islamabad-Rawalpindi area. Women of reproductive age were randomly interviewed during field visits to communities. Information regarding the pertinent variables was obtained with the help of questionnaires specially designed for this purpose


Aim was to analyze possible association of tubal ligation with gynecological complications collectively called “post tubal ligation syndrome”. The collection of data for analysis was done by direct face-to-face interviews of women involved retrospective cohort study for analysis of relative risk for post ligation gynecological and health condition of the ligated cohort. Both control cohort and ligated cohort were recruited by visiting communities through Community Health Houses (CHH)(Period: 1998-2000).


For purposes of the investigation, women illnesses was considered to be any complaint pertaining to menstrual impairment, postmenopausal bleeding (PMB), uterine pathology, vaginal discharge (infection) and utero-vaginal prolapsed (UVP) for which a woman must consult a gynecologist. The rationale of variables was based on the reported risk factors, conditions and status contributing to a particular gynecological disorder.


Ethical considerations:


Verbal consent of the subjects for participation in the study was obtained before conducting interviews. The subjects were assured of confidentiality of their identity. The data were, thus, entered by a code number allotted to individual subjects.


Analysis of data:


Analysis of data was done on group basis and not on individual basis. The data obtained were coded for type of study and the selected variables, followed by entry for analysis using SPSS Version 8. Computer Programme For the purpose of analysis, the multiple outcomes were reduced to a dichotomous outcome (i.e. yes/no)


Field Visits:


The Prime Minister’s Programme (now named as Women’s Health Project, Ministry of Health, Islamabad) on Family Planning has been providing nationwide services to communities through trained lady health workers. The territory under the Federal Area of Islamabad comprises low income urban as well as rural areas in its vicinity. A supervisory team performs routine monitoring and holds family planning camps in coordination with the District Population Office, which provides services and follow up at the community level. The field visits were coordinated with this team after formal approval of the relevant authorities. Visits were made routinely to interview women at their homes. The communities are looked after by lady health workers located in Community Health Houses that maintain demographic and reproductive health records of the resident women. Since the resident women are familiar with the lady health workers, they do not hesitate to seek their assistance regarding day-to-day mother-child problems, general awareness of and motivation for health education, family planning and contraceptive supply.


Baseline data pertaining to social characteristics, demographic factors, reproductive characteristics and health status were recorded along with post ligation health status and reproductive history.


This community-based study was conducted by visiting women in their homes in communities surrounding the area of Islamabad and Rawalpindi. Women who had undergone tubal ligation at any stage of their life were interviewed. The aim of the visit was to assess prevalence of postligation complications, if any, and to circumvent hospital bias by asking questions in a hospital-free setting. The descriptive information covered age at ligation, parity, and method of ligation, time since ligation, health status and possible gynecological disorders. The calculated sample size turned out to be 500 (95% confidence level) but only 89% response rate could be achieved (N= 447).


 Questions were asked regarding their health and gynecologic condition especially menstrual cycle, previous contraceptive use and time since gynecological problem. Visit to gynecologist or use of medication for gynecological problem was taken as indicator of presence of gynecological disorders. The criterion of selection as cohort for interview was “Pakistani women of over 30 years and ligated at least 6 months prior to the interview”. The information collected on health and gynecological status was based on self-report. The control cohort consisted of women residing in the same community.




Demographic features:


Partitioning of the ligated cohort ( N=447) on the basis of incidence of Gynecological disorder (GD) or lack there of yielded 165 (37.92%) women with GD and 282 (63.1%) without GD (Table 1).In contrast, the corresponding percentages for the control cohort (nonligated, N=507) yielded only 15% women with GD. There were no marked between and within group differences in average age of the women at the time of postligation interview. The time age and number of abortions (Table 1). The notable aspect of the comparison, thus, was a markedly greater incidence of GD in the ligated cohort compared to the control cohort (nonligated) (Figure 1), and that the onset of GD in the ligated cohort occurred with considerable delay after ligation.


Table 1.  Baseline statistics of total sample of women  (N=954). Data (mean + SD) based on information collected at the Community Health House (hospital-free environment) as part of the study on postligation health and gynecological status. Ligated Cohort (ligated) and Control Cohort (nonligated) are dichotomized as GD and No GD subgroups.



Ligated Cohort  (447)



Control Cohort (507)


(165, 37%)


 (282, 63%)




 (76, 15%)


 (431, 85%)

Age (yr)





Time Since

Married (yr)


19.2+ 6.8



Time Since

Ligation (yr)





Time Since

GD (yr)





Conception (No.)





LCB (yr)





Abortion (No.)







Health characteristics:


Table 2 shows age distribution, marriage duration and health status of the women of both the cohorts, each partitioned into GD and No GD subgroups. Regardless of GD status, the majority of the women in the two groups (ligated cohort and control cohort) were over 30 yrs of age (premenopausal range) and married for over 10 yrs. In the control cohort , a greater percentage of women in both subgroups (GD, No GD) had a parity of < 5 (>70%) compared to the ligated cohort (lesser pregnancy burden). In both subgroups of the ligated cohort, parity of < 5 or > 5 was in a ratio of nearly 50:50. There were no marked between group or within group differences in respect to abortion rate. The majority of women in both subgroups of the two cohorts did not experience abortion (67-75%). In both the cohorts, a markedly high percentage of women were not using contraceptives.  However, a noticeably higher percentage of control cohort with GD were on contraceptives. Both cohorts had previously experienced surgery other than ligation surgery. In the ligated cohort, the percentage of women exposed to such surgery was much lower in both subgroups (GD, No GD) compared to the control cohort subgroups. In the control chorot, a higher percentage of women with GD experienced such surgery as opposed to the No GD subgroup (51 vs 33%). Such a trend was evident in the ligated cohort too (21.8 vs 15.9%). The majority of women (over 78%) in the two subgroups of the ligated cohort had no surgical history of this kind. The majority of women in the No GD subgroup of the ligated cohort and in both subgroups of the control cohort were free of health problems (Table 2). However, the GD women in both the ligated and control cohort had substantially greater incidence of health problems (40% and 17.2% respectively) (Figure 2) than the No GD subgroup. It should also be noted that the collective percentage of women with health problems was greater in the ligated than in the control cohorts.


Table 2. Baseline statistics of total sample of women (N=954). Data based on information collected at the Community Health House as part of the study on post ligation health and gynecological status.



Ligated cohort (447)


Control cohort (507)

GD (165)

No GD (282)


GD (76)

No GD (431)










*Age at Interview

<30 y

>30 y



























Time Since Married

<10 y

>10 y















































































>1 yr



























Contraceptive Use:





























Surgery History:





























*Health Problem:





























*post ligation

Figure 1



Figure 2




The study  (ligated vs nonligated control cohort) dichotomized into GD and No GD subgroups revealed (1) two fold greater risk of GD in the ligated cohort than in the control cohort (nonligated), and (2) fairly close correspondence regarding mean age, duration of marriage, abortion rate, LCB and contraception. The majority of women in this sub sample were over 30 yrs of age, were married for over 10 yrs, had no experience of abortion, had LCB of > 1 yr (cessation of further pregnancies) and yet were non users of contraceptives. Some notable differences pertained to noticeably higher percentage of women with experience of surgery other than ligation (perhaps pregnancy-related). Furthermore, a substantially greater percentage of women had health problems in the GD subgroup of both the ligated and control cohorts as compared to the No GD subgroup of these cohorts, suggesting an association of GD with health problems. However of those women that had GD, health problems were far greater in the ligated cohort compared to the control cohort indicating increased risk of GD in the former cohort. Also, onset of GD occurred about 2 yrs after ligation suggesting possibility of a biological basis of such change.


Prospective studies in the past on effect of tubal ligation on reproductive health and gynecological status, two or more years after surgery, have yielded conflicting results. Studies, where women have been observed for 4-6 years after surgery, have yielded only equivocal evidence of menstrual disturbance following ligation13-16. Self report and hospital-based data gave generally similar evidence regarding GD and ligation. Often, self-reports underestimate the gravity of the problem as has been observed by Bhatia et al.17 in a study in South Indian women. Depending on the site of puncture for sterilization, herniation has been recorded in several studies18-22, highlighting a surgical procedural complication as is also evident in a small percentage of sterilized women in the present study (data not reproduced here). Sterilization has been shown to reduce the risk of pelvic inflammatory disease (PID) by preventing spread of infection from the lower genital tract to the peritoneal cavity16,23-26. Some reports, however, have given contrary results in this regard indicating that the protection is not absolute24,27-29. Sterilization is known to provide several other advantages in terms of health of ligated women. One of these is reduced risk of ovarian cancer. This has been found to be true in spite of a maximum period of 15 years of observation following sterilization. This advantage  seems to result from protection of the ovaries against oncogenic viruses30 and environmental carcinogens that may be inadvertently introduced into the vagina or the perineum31-36.


The study revealed that ligation has an increased  risk for gynecological disorders, especially menstrual disturbance, as well as health complications. The onset of GD occurred in the ligated women with a delay. Studies during the last two decades or so have yielded considerably discordant information on gynecological morbidity and its relationship with sterilization13-16,27. Several investigators have presented evidence that tubal ligation results in what has been described as post-tubal ligation syndrome. Yet the existence of this syndrome has been widely debated by others. A major reason for the debate has been lack of consensus on its precise definition. According to one view, it is a complex of largely psychosomatic symptoms dominated by menstrual disorders37-40. Another view states that it is characterized by increased menstrual flow or cramps, increased premenstrual syndrome and gynecological problems in general with the additional implication that sterilization speeds up menopause6. Peterson et al.41 have argued that the debate on existence of post tubal ligation syndrome persists not only because the syndrome has been ill defined but also because many women show menstrual abnormalities after sterilization.


 They further state that the two are coincidental simply because both sterilization and menstrual disorders are quite common. Earlier reviews42 ; 43;44 on the subject dealt with gynecological status and emotional consequences of tubal ligation when neither the technology was very advanced nor ligation was a preferred recourse. It has been reported that one of the most common postligation gynecological symptoms is dysfunctional uterine bleeding 43;45;46. This has been observed in the present investigation as well. That tubal ligation is followed by a sequence of menstrual alterations has also been demonstrated in more recent studies47-51 . Other investigators8;15, 52  have not been able to confirm this observation. Evidently, the conflict seems to stem from lack of appropriate controls for confounders in the study designs of some of the studies. Thus, it has been noted that the evidence of positive association of ligation with GD presented by some of the investigators43,53; 54;55; 56 suffers from lack of adjustments for contraceptive usage, pre-existing gynecological diseases, age, education, parity, gravidity and even the additional constraint of recall bias vis-à-vis menstrual history. Also, where perimenopausal women dominate the study population, the chances of disturbed menstrual cycle increase simply because of approaching menopause. In retrospective analysis of postligation syndrome, recall of menstrual parameters several years later introduces a bias that confounds proper evaluation of the data. In a large number of studies, where the subjects have been on oral contraceptives prior to ligation, the women tend to develop postligation menstrual disorders as a result of cessation of contraception41. This observation has been substantiated by negative evidence of association with menstrual disturbance following exclusion of such subjects from the analysis57. In their study, Vessey et al.16 could hardly find any evidence of long term sequalae of tubal ligation. On the other hand, Martinez-Schnell et al. 9 examined postligation menstrual complications in a multicenter prospective study of 5000 women and concluded that there is an increase in odds of risk of at least one of the several menstrual dysfunctions in the 5th year of follow up compared to the early postligation period. Increase in risk of menstrual dysfunction in yearly follow up has also been reported by Goldhaber et al..

The ensuing GDs consequent to ligation as reported in the present work do not appear to be a consequence of surgical procedure but outcome of biological alterations in, perhaps ovarian hormonal physiology ensuing from vascular modifications and subsequent ovarian dysfunction. Thus, from the standpoint of local family planning programmes and policies aimed at safeguarding the reproductive health of women and to curtail unwanted pregnancies, recourse to female sterilization requires enhanced services for long term ligated women to ensure their health post ligation and thus remove the apprehensions and fear for opting for the procedure by other women.




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