Medical Hypotheses (1990) 31. IY7-iYY 0 Longman Group UK Ltd IYSK)
Suicide and the Menstrual
Cycle
D. LESTER Richard Stockton State College, Department
of Psychology,
Pomona,
NJ 08240, USA
Abstract-A
review of studies on the variation in suicidal behavior over the menstrual cycle identified only five studies with data presented in sufficient detail that they could be pooled, providing a sample of 400 menstruating women. A deficit in acts of attempted suicide in week three of the cycle was revealed, and it was suggested that this supports a hormonal explanation of the variation.
Introduction
Investigators have long been interested in the variation of behavior in women over the menstrual cycle. If behavior does show such a variation, the variation may support psychological theories about the cause of the behavior, since the variation can be attributed to variations in mood over the menstrual cycle, but it may also support physiological theories about the cause of the behavior since the levels of circulating hormones vary over the menstrual cycle. In particular, the premenstrual syndrome, a combination of hormonal and mood changes that occur prior to the bleeding phase of the menstrual cycle, has long been though to be important in determining behavior. Whether the hormonal changes or the psychological changes are emphasized (or whether indeed the syndrome is viewed as simply a product of societal expectations and labelling) changes with the era (1). One behavior that has aroused considerable interest for its variation with the menstrual cycle is suicide. The sex difference in suicidal behavior,
with men completing suicide (that is, dying) more than women and women attempting suicide (and surviving) more than men, has been well documented (2). The variation in acts of attempted suicide over the menstrual cycle may be responsible for the excess number of acts of attempted suicide in women. A recent review of thirteen studies on this topic concluded that the frequency of attempted suicide did vary over the menstrual cycle (3). All of the studies reported on very small samples of women, and the present paper explores these studies in greater depth and combines their data in order to ascertain whether there is indeed a statistically significant variation in suicidal behavior over the menstrual cycle.
Studies on attempted suicides
Of the eleven studies on attempted suicides reviewed (3). three did not study actual attempted suicides. Mandell et al (4, 5) studied
197
198 Table 1A
MEDICAL HYPOTHESES
Data on the number of women attempting suicide in each period of their menstrual period Birtchnelf & Floyd (I 974)
Pa& & Holding (1976)
Tonks, et al. (1968)
Total
A veragef Day
days 1-4 5-7 8-14 15-21 22-24 25-28
12 13 23 14 5 9
15 17 29 18 16 19
15 7 I9 19 11 24
42 37 71 51 32 52
10.5 12.3 10.1 7.3 10.7 13.0
total
76
114
95
285
10.2
X’ = 10.10. df = 3, p < 0.02
Table 1B Birtchnell & Floyd (1974)
Pallis & Holding (I 976)
Tonks, et al. (1968)
Holding & Minkoff (1973)
Ekberg et al. (I 986)
Total
Average/Day
days: l-7 B-14 15-21 22-28
25 23 14 14
32 29 18 35
22 19 19 35
19 20 16 19
13 13 6 9
111 104 73 112
15.6 14.9 10.4 16.0
total
76
114
95
74
41
400
14.3
X’ = 10.37, df = 5,
not significant
callers to a suicide prevention centre, while Glass (6) studied suicidal ideation in female psychiatric emergencies. Of the remaining eight studies, one provides the number of women on each day of the cycle (7) and two others provide a breakdown by the same uneven pattern of days (l-4,5-7,8-14,1522, 22-24, 25-28) (8, 9). Two further studies provide data by week (10, 11). Both Dalton and Trautman (12, 13) used intervals which have not been used by any other investigator, and their data cannot be included in. Buckle (14) did not report their data, but only their conclusion. The result is that three studies can be used to provide a combined sample of 285 menstruating women studied over six periods of the menstrual cycle (Table lA), while five studies can be used to provide a combined sample of 400 menstruating women over the four weeks of the menstrual cycle (Table 1B). A statistical analysis of the sample of 285 menstruating women over six periods of the menstrual cycle showed a premenstrual increase
in frequency and a decrease in days 15-21, but this variation was not statistically significant. In contrast, a division by week, using the expanded sample now possible of 400 menstruating women, found a significant difference, with a deficit of women in days 15-21 (roughly the mid-luteal phase). This deficit is probably valid since the practice of investigators of artificially shortening the cycle to 28 days in all women, many of whom do not have an exactly 28-day cycle, might affect the numbers of women in days 22-28, but would not be expected to increase the numbers of women in the first three weeks of the cycle. Thus, the fact that the number of women in week three is less than the number in weeks one and two is probably not due to this artificial shortening of the cycle to 28 days. It is interesting to note that there does not appear to be a great premenstrual increase as compared to weeks one and two. Rather it is the deficit in week three that is striking in these data. However, we must remember that it is by no means clear whether the data represent a
SUICIDE AND THE MENSTRUAL
199
CYCLE
decreased frequency in week three or an increased frequency in the other weeks.
References
Completed suicides
Two studies have appeared on completed suicides. Ribeiro (15) reported on eleven women committing suicide by burning in Kenya and did not give the exact number by week of the cycle. MacKinnon (16) reported on only 38 suicides, using time periods that do not match those by the investigators of attempted suicides. Thus, these data cannot be combined to provide a more meaningful sample.
5. 6. 7.
Discussion We have seen that only five studies of the variation of suicidal acts over the menstrual cycle provide data that are comparable so that the small sample can be combined to provide more reliable results. It is imperative that future investigators of this topic report their data day by day, so that their results can be compared and combined with those of other investigators. Reliable findings are possible only for attempted suicides, for which it appears that there is a deficit in acts during days 15-21 of the cycle. During this period, the levels of circulating estrogen and progesterone are high (17). Researchers interested in variations in mood do not report particular mood states for this period. Thus, the data do support a hormonal basis for the variation rather than a psychologal/mood basis. Since estrogens may suppress dopamine levels in the brain and since high dopamine levels may be associated with increased depression, the high levels of circulating estrogen in week three of the menstrual cycle may lower levels of depression by reducing the levels of dopamine in the brain (18, 3).
8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18.
M Parlee. The premenstrual syndrome. Psychological Bulletin, 80: 454-465. 1973. D Lester. Suicide. In C S Widom (Ed.) Sex roles and nsvchonatholoav. New York: Plenum. 145-1.56. 1984. D’ Lester. WKy women kill themselves. Springfield, Thomas, 1988. A J Mandell and M P Mandell. Suicide and the menstrual cycle. Journal of the American Medical Association, 200: 792-793, 1967. R Wetzel. T Reich and J McClure. Phase of menstrual cycle and self-referral to a suicide prevention center. British Journal of Psvchiatrv. 119: 523-524. 1971. G Glass, G Heninger’, M Lansky and K Talan. Psychiatric emergencies related to the menstrual cycle. American Journal of Psychiatry, 128: 705-711, 1971. C M Tonks. P H Rack and M J Rose. Attempted suicide and the menstrual cycle. Journal of Psychosomatic Research, 11: 319-327, 1968. J Birtchnell and S Floyd. Attempted suicide and the menstrual cvcle. Journal of Psvchosomatic Research. , 18: 361-369: lY74. D Pallis and T Holding. The menstrual cycle and suicidal intent. Journal of Biosocial Science. 8: 27-33. 1976. 0 Ekberg. D Jacobsen, Y Sorum and G Aass. Selfpoisoning and the menstrual cycle. Acta Psychiatrica Scandinavia, 73, 239-241: 1986. T Holding and K Minkoff. Parasuicide and the menstrual cycle. Journal of Psychosomatic Research, 17: 365-368, 1973. K Dalton. Menstruation and acute psychiatric illness. British Medical Journal. 1: 148-149. 1959. E A Trautman. The suicidal fit. Archives of General Psychiatry, 5: 76-83, 1961. R C Buckle. J Linane and N McConaghy. Attempted suicides presenting at the Alfred Hospital. Medical Journal of Australia. I: 754-758. 1965. A L Ribeiro. Menstruation and crime. British Medical Journal, I: 604. 1961. I L McKinnon, P McKinnon and A D Thomson. Lethal hazards of the luteal phase of the menstrual cycle. British Medical Journal. 1: 1015. 1959. A C Guyton. Function of the human body. Philadelphia: Saunders. 1959. G Skutch. Manic-depression. Medical Hypotheses, 7: 737-746.1981.
Suicide and the Menstrual
Cycle
D. LESTER Richard Stockton State College, Department
of Psychology,
Pomona,
NJ 08240, USA
Abstract-A
review of studies on the variation in suicidal behavior over the menstrual cycle identified only five studies with data presented in sufficient detail that they could be pooled, providing a sample of 400 menstruating women. A deficit in acts of attempted suicide in week three of the cycle was revealed, and it was suggested that this supports a hormonal explanation of the variation.
Introduction
Investigators have long been interested in the variation of behavior in women over the menstrual cycle. If behavior does show such a variation, the variation may support psychological theories about the cause of the behavior, since the variation can be attributed to variations in mood over the menstrual cycle, but it may also support physiological theories about the cause of the behavior since the levels of circulating hormones vary over the menstrual cycle. In particular, the premenstrual syndrome, a combination of hormonal and mood changes that occur prior to the bleeding phase of the menstrual cycle, has long been though to be important in determining behavior. Whether the hormonal changes or the psychological changes are emphasized (or whether indeed the syndrome is viewed as simply a product of societal expectations and labelling) changes with the era (1). One behavior that has aroused considerable interest for its variation with the menstrual cycle is suicide. The sex difference in suicidal behavior,
with men completing suicide (that is, dying) more than women and women attempting suicide (and surviving) more than men, has been well documented (2). The variation in acts of attempted suicide over the menstrual cycle may be responsible for the excess number of acts of attempted suicide in women. A recent review of thirteen studies on this topic concluded that the frequency of attempted suicide did vary over the menstrual cycle (3). All of the studies reported on very small samples of women, and the present paper explores these studies in greater depth and combines their data in order to ascertain whether there is indeed a statistically significant variation in suicidal behavior over the menstrual cycle.
Studies on attempted suicides
Of the eleven studies on attempted suicides reviewed (3). three did not study actual attempted suicides. Mandell et al (4, 5) studied
197
198 Table 1A
MEDICAL HYPOTHESES
Data on the number of women attempting suicide in each period of their menstrual period Birtchnelf & Floyd (I 974)
Pa& & Holding (1976)
Tonks, et al. (1968)
Total
A veragef Day
days 1-4 5-7 8-14 15-21 22-24 25-28
12 13 23 14 5 9
15 17 29 18 16 19
15 7 I9 19 11 24
42 37 71 51 32 52
10.5 12.3 10.1 7.3 10.7 13.0
total
76
114
95
285
10.2
X’ = 10.10. df = 3, p < 0.02
Table 1B Birtchnell & Floyd (1974)
Pallis & Holding (I 976)
Tonks, et al. (1968)
Holding & Minkoff (1973)
Ekberg et al. (I 986)
Total
Average/Day
days: l-7 B-14 15-21 22-28
25 23 14 14
32 29 18 35
22 19 19 35
19 20 16 19
13 13 6 9
111 104 73 112
15.6 14.9 10.4 16.0
total
76
114
95
74
41
400
14.3
X’ = 10.37, df = 5,
not significant
callers to a suicide prevention centre, while Glass (6) studied suicidal ideation in female psychiatric emergencies. Of the remaining eight studies, one provides the number of women on each day of the cycle (7) and two others provide a breakdown by the same uneven pattern of days (l-4,5-7,8-14,1522, 22-24, 25-28) (8, 9). Two further studies provide data by week (10, 11). Both Dalton and Trautman (12, 13) used intervals which have not been used by any other investigator, and their data cannot be included in. Buckle (14) did not report their data, but only their conclusion. The result is that three studies can be used to provide a combined sample of 285 menstruating women studied over six periods of the menstrual cycle (Table lA), while five studies can be used to provide a combined sample of 400 menstruating women over the four weeks of the menstrual cycle (Table 1B). A statistical analysis of the sample of 285 menstruating women over six periods of the menstrual cycle showed a premenstrual increase
in frequency and a decrease in days 15-21, but this variation was not statistically significant. In contrast, a division by week, using the expanded sample now possible of 400 menstruating women, found a significant difference, with a deficit of women in days 15-21 (roughly the mid-luteal phase). This deficit is probably valid since the practice of investigators of artificially shortening the cycle to 28 days in all women, many of whom do not have an exactly 28-day cycle, might affect the numbers of women in days 22-28, but would not be expected to increase the numbers of women in the first three weeks of the cycle. Thus, the fact that the number of women in week three is less than the number in weeks one and two is probably not due to this artificial shortening of the cycle to 28 days. It is interesting to note that there does not appear to be a great premenstrual increase as compared to weeks one and two. Rather it is the deficit in week three that is striking in these data. However, we must remember that it is by no means clear whether the data represent a
SUICIDE AND THE MENSTRUAL
199
CYCLE
decreased frequency in week three or an increased frequency in the other weeks.
References
Completed suicides
Two studies have appeared on completed suicides. Ribeiro (15) reported on eleven women committing suicide by burning in Kenya and did not give the exact number by week of the cycle. MacKinnon (16) reported on only 38 suicides, using time periods that do not match those by the investigators of attempted suicides. Thus, these data cannot be combined to provide a more meaningful sample.
5. 6. 7.
Discussion We have seen that only five studies of the variation of suicidal acts over the menstrual cycle provide data that are comparable so that the small sample can be combined to provide more reliable results. It is imperative that future investigators of this topic report their data day by day, so that their results can be compared and combined with those of other investigators. Reliable findings are possible only for attempted suicides, for which it appears that there is a deficit in acts during days 15-21 of the cycle. During this period, the levels of circulating estrogen and progesterone are high (17). Researchers interested in variations in mood do not report particular mood states for this period. Thus, the data do support a hormonal basis for the variation rather than a psychologal/mood basis. Since estrogens may suppress dopamine levels in the brain and since high dopamine levels may be associated with increased depression, the high levels of circulating estrogen in week three of the menstrual cycle may lower levels of depression by reducing the levels of dopamine in the brain (18, 3).
8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18.
M Parlee. The premenstrual syndrome. Psychological Bulletin, 80: 454-465. 1973. D Lester. Suicide. In C S Widom (Ed.) Sex roles and nsvchonatholoav. New York: Plenum. 145-1.56. 1984. D’ Lester. WKy women kill themselves. Springfield, Thomas, 1988. A J Mandell and M P Mandell. Suicide and the menstrual cycle. Journal of the American Medical Association, 200: 792-793, 1967. R Wetzel. T Reich and J McClure. Phase of menstrual cycle and self-referral to a suicide prevention center. British Journal of Psvchiatrv. 119: 523-524. 1971. G Glass, G Heninger’, M Lansky and K Talan. Psychiatric emergencies related to the menstrual cycle. American Journal of Psychiatry, 128: 705-711, 1971. C M Tonks. P H Rack and M J Rose. Attempted suicide and the menstrual cycle. Journal of Psychosomatic Research, 11: 319-327, 1968. J Birtchnell and S Floyd. Attempted suicide and the menstrual cvcle. Journal of Psvchosomatic Research. , 18: 361-369: lY74. D Pallis and T Holding. The menstrual cycle and suicidal intent. Journal of Biosocial Science. 8: 27-33. 1976. 0 Ekberg. D Jacobsen, Y Sorum and G Aass. Selfpoisoning and the menstrual cycle. Acta Psychiatrica Scandinavia, 73, 239-241: 1986. T Holding and K Minkoff. Parasuicide and the menstrual cycle. Journal of Psychosomatic Research, 17: 365-368, 1973. K Dalton. Menstruation and acute psychiatric illness. British Medical Journal. 1: 148-149. 1959. E A Trautman. The suicidal fit. Archives of General Psychiatry, 5: 76-83, 1961. R C Buckle. J Linane and N McConaghy. Attempted suicides presenting at the Alfred Hospital. Medical Journal of Australia. I: 754-758. 1965. A L Ribeiro. Menstruation and crime. British Medical Journal, I: 604. 1961. I L McKinnon, P McKinnon and A D Thomson. Lethal hazards of the luteal phase of the menstrual cycle. British Medical Journal. 1: 1015. 1959. A C Guyton. Function of the human body. Philadelphia: Saunders. 1959. G Skutch. Manic-depression. Medical Hypotheses, 7: 737-746.1981.
