PMS and OCs
1
RUNNING HEAD: Why do women on OCs experience PMS?
Answering the Question: If combined oral contraceptives work by keeping a woman’s hormonal cycle from fluctuating, thereby preventing ovulation, why do women taking the pill still suffer from PMS? Travis Sky Ingersoll
PMS and OCs
2
If combined oral contraceptives work by keeping a woman’s hormonal cycle from fluctuating, thereby preventing ovulation, why do women taking the pill still suffer from PMS?
Before exploring the role of contraceptive use in relation to premenstrual syndrome (PMS), it is best to provide an overview of the definition of PMS, what causes its symptoms, and what treatments are currently available to ameliorate symptoms. A brief review of how oral contraceptives (OCs) work is given in order to help understand OCs role in producing symptoms of PMS. We will conclude with a brief review of new OCs that promise to virtually eliminate menstruation and possibly even PMS. What exactly is premenstrual syndrome? A syndrome is a group of symptoms that occur together, and in the case of PMS those symptoms are in relation to the female’s menstrual cycle. With PMS, physical symptoms may include cramps, dizziness, backache, fatigue, nausea, a tingling in the extremities, abdominal bloating, breast tenderness, breast swelling, change in appetite, thirst, edema, and increased body weight. Psychoemotional symptoms may include anxiety, tension, irritability, depression, mood swings, crying spells, decreased interest, insomnia, feeling out of control, and an inability to concentrate (Backstrom et al., 2003; Hatcher, 2004; Jones & Lopez, 2006). For women whose PMS symptoms have a significant, negative impact on their daily life, a diagnosis of premenstrual dysphoric disorder (PMDD) could be made according to the criteria set by the American Psychiatric Association’s DSM-IV (1994).
PMS and OCs
3
How many women suffer from premenstrual syndrome? According to Jones and Lopez (2006) around 70% - 90% of women suffer from some kind of physical and/or emotional symptoms associated with their menstrual cycle. Around 20% to 30% experience moderate to severe PMS, while another 1% - 10% are debilitated by the severity of their symptoms (Hatcher et al., 2004). What mechanisms cause premenstrual syndrome? The truth of the matter is that nobody really knows what the exact mechanisms underlying many of the symptoms associated with PMS are. However there are a number of researched-backed theories which offer some insight on this physiological/psychoemotional phenomenon. PMS is understood as a result of various neurochemical and physiological interactions that take place due to the cyclic dispersal of gonadotropins. Due to the interactions between the brain and secreted hormones, it is generally agreed that the ovaries, and in particular the corpus luteum, are at the root of PMS (Backstrom et al., 2003; Freeman et al., 2001; Jones & Lopez, 2006). The corpus luteum forms in the follicular cavity left by the expelled egg during ovulation. This process occurs during the second half of the menstrual cycle. Lutenizing hormone (LH) peaks during ovulation and is understood to be the primary compound responsible for the formation and function of the corpus luteum, which is to secrete progesterone and estradiol (Jones & Lopez, 2006). The hormones secreted prime the uterus for the possible implantation of a fertilized ovum. If the egg is not fertilized the corpus luteum disintegrates, during which time PMS symptoms also disappear (Freeman et al., 2001). If however, fertilization does occur, the corpus luteum continues producing progesterone and estradiol until the developing embryo takes over the process of
PMS and OCs
4
hormone secretion. Research has found that during anovulatory cycles, such as those induced by the use of some oral contraceptives, or for any other reason, the corpus luteum is not formed and PMS symptoms are either improved or absent (Hamarback & Backstom, 1988; Mortola, Girton, & Fisher, 1991). Estradiol, progesterone and progesterone metabolites appear to be the primary catalysts for experiencing PMS in susceptible women. We mention PMS susceptibility due to the fact that not every woman will ever experience PMS, and research has shown no difference in progesterone and estradiol levels between women who suffer from PMS and those who do not (Backstrom et al., 2003). With regard to PMS, levels of estradiol and progestogens appear to affect the GABA and serotonin systems, but also have been shown to influence norepinephrine and endorphin production (Jones & Lopez, 2006). How this gonadotropin influence on the GABA system and serotonin levels works to produce symptoms of PMS is not completely understood yet. However, when women suffering from PMS are given selective serotonin reuptake inhibitors (SSRIs), a significant decrease in PMS symptoms is produced (Kouri, E. M. & Halbreich, U., 1997). What treatment options are available for PMS? As was mentioned, SSRIs have been shown to be effective in treating the psychoemotional symptoms of PMS, and have been shown to improve some women’s physical symptoms as well (Hatcher et al., 2004). Of course the specific kind of SSRI used, such as fluoxetine (Prozac), alprazolam (Xanax), or sertraline, would impact the specific symptoms alleviated. With regard to dosage, SSRIs have been found to be effective when taken continuously, but also can be taken in a cyclic manner, such as only during the last 14 days of the menstrual cycle
PMS and OCs
5
(Backstrom et al., 2003; Hatcher et al., 2004). However, one of the most common side effects of using SSRIs is sexual dysfunction. Another route in the treatment of PMS is administering high doses of gonadotrophinreleasing hormone (GnRH) agonists (Jones & Lopez, 2006). The use of GnRH agonists result in extremely low progesterone and estrogen blood serum levels, thereby causing a reduction in the secretion of follicle-stimulating hormone (FSH) and LH by the pituitary gland (Freeman et al., 2001). Due to the reduction of FSH and LH, anovulation and amenorrhoea result. Anovulation means not ovulating, while amenorrhoea refers to a cease of menstruation. Both physiological and psychoemotional symptoms are alleviated using this method of treatment. The primary drawbacks of using GnRH agonists in the treatment of PMS are a loss of bone density, possible impairment in cognitive functioning, and postmenopausal symptoms (Backstrom et al., 2003). Surgical oophorectomy is yet another option. Performing an oophorectomy means that the ovaries are completely removed. Although this treatment method for PMS is drastic and should only be used when all other options have been exhausted, substantial reduction of symptoms have been documented (Backstom et al., 2003). It should be mentioned that many of the treatment options being reviewed are intended to treat severe forms of PMS, there are many less-drastic options available as well. Exercise and dietary manipulations have also been shown to reduce symptoms for those experiencing mild forms of PMS. Minimizing consumables such as alcohol, caffeine, sugar and salt have been found to help (Jones & Lopez, 2006). Vitamin therapy has also shown promise. In particular, vitamin B6 has shown to produce significant improvement in PMS symptoms (Abraham & Hargrove, 1980). However, other studies have indicated
PMS and OCs
6
no such improvement using vitamin B6 (London & Bradley, 1991). Of course there’s always Midol. In addition there has also been research pointing to the effectiveness of an extract of the chaste tree or chasteberry. In a randomized, placebo controlled study by Schellenberg (2001), 178 women who experience PMS were either given a chasteberry tablet or a placebo pill once daily. Participants taking the chasteberry tablets communicated a significant improvement in PMS symptoms on 5 of the 6 self-assessment items. Alleviated symptoms included irritability, anger, mood-alteration, headache and breast fullness. The only symptom not relieved was bloating (Huddleston & Jackson, 2001). To begin to answer the question posed at the beginning of this paper, we will now review the use of oral contraceptives in the treatment of PMS. Theoretically, oral contraceptives should decrease PMS symptoms since they inhibit ovulation. This is accomplished by giving the female body a constant, and somewhat elevated, dose of estrogen, progesterone, or a combination of both (Jones & Lopez, 2006). Estrogen inhibits ovulation, while progesterone thins the endometrium and thickens cervical mucous (Hatcher et al., 2004). However, simply inhibiting ovulation does not appear to be the cure-all for PMS sufferers. Research has found that oral contraceptives containing estrogen are often effective in alleviating physical symptoms, but not psychoemotional symptoms, and add insult to injury by decreasing sexual interest (Backstrom et al., 2003; Graham & Sherwin, 1992). Progesterone-only contraceptives all seem to result in negative mood changes and physical symptoms (Backstrom et al., 2003). In general various treatments using
PMS and OCs
7
estrogens and progestogens have produced inconsistent results with regard to alleviating PMS symptoms (Bancroft & Rennie, 1993; Hatcher et al., 2004; Jones & Lopez, 2006). What role do oral contraceptives play in the experience of PMS? Evidence from studies examining the effects of postmenopausal, or post-oophorectomy hormone replacement therapy (HRT), point to a primarily neurochemical basis for PMS (Backstrom et al., 2003; Casper et al., 1990). Literature indicates an interaction between hormones and the brain’s response systems. Women with a history of PMS, who had undergone both a surgical oophorectomy and a hysterectomy, could be safely be given estrogen-only replacement therapy without experiencing a reoccurrence of symptoms (Feeman et al., 2001). With regard to GnRH agonist therapy, women whose symptoms improved significantly all suffered a reoccurrence of PMS when estrogen and progesterone addback therapy was administered (Mortola, Girton, & Fischer, 1991; Mezrow et al., 1994). It is the combination of estrogen and progestin that appears responsible for the experience of symptoms associated with PMS. Estrogen alone does not appear to create PMS symptoms. The question then is, why not just use estrogen only pills? There is, in fact, a very good reason not to. Due to the strong correlation between estrogen replacement therapy (ERT) and endometrial cancer, adding progestogen is advised due to studies indicating that its addition significantly decreases the risk for such cancers (Jones & Lopez). In conclusion, PMS symptoms are not solely the result of hormonal fluctuations due to a woman’s menstrual cycle. This is why women with a history of PMS still experience symptoms even when their hormonal systems are kept in homeostasis and they are not
PMS and OCs
8
ovulating. The mechanisms producing PMS are much more complex than that. The experience of PMS is due to the way in which certain women’s bodies process neurochemical agents, in particular the combination of estrogen and progesterone. However there does seem to be a degree of psychosomatic influence indicated by high placebo response rates in many studies on the treatment of PMS and PMDD (Freeman & Rickels, 1999; Freeman et al., 2001; Yonkers, Clark & Trivedi, 1997). Is the end of menstruation and PMS in the foreseeable future? With recent advances in oral contraceptive technology, such a possibility may already be a reality. As far as eliminating menstruation, there are already a few products on the market such as Seasonale that can be taken for 84 consecutive days. After the 84 days of taking the pill, seven days of placebo pills are given to promote a progesterone cycle withdrawal bleed. Even in the light of side effects such as spotting, in 2004 sales for Seasonale were around $87 million (George, 2005). Two new oral contraceptives, Anya and Belara both promise to give women complete choice over menstruation. Both can be taken 365 days a year without the need for placebos. Unless the user wants to experience a withdrawal bleed, which they could for a variety of reasons, they do not have to (Bitzer, 2005; George, 2005). Although both Anya and Belara claim to lessen, or even eliminate symptoms associated with PMS, further research is needed to ascertain whether both forms of contraceptive can actually live up to that claim. As we have learned, simply producing a state of anovulation and amenorrhea does not necessarily translate into an absence of PMS. Although our understanding of PMS continues to advance, it is evident that we still have a lot to learn.
PMS and OCs References Abraham, G. E., & Hargrove, J. T. (1980). Effect of vitamin B6 on premenstrual symptomatology in women with premenstrual tension syndrome: A double-blind crossover study. Infertility, 3, 155-165. American Psychiatric Association (1994). Diagnostic and statistical manual of mental disorders (4th ed.), 714-718, Washington, DC: American Psychiatric Association. Backstrom, T., Andreen, L., Birzniece, V., Bjorn, I., Johansson, I., Nordenstam-Haghjo, M., Nyberg, S., Sundstrom-Poromaa, Wahlstrom, G., Wang, M., & Zhu, D. (2003). The role of hormones and hormonal treatments in premenstrual syndrome. CNS Drugs, 17, 5, 325-342. Bancroft, J., Rennie, D. (1993). The impact of oral contraceptives on the experience of perimenstrual mood, clumsiness, food craving and other symptoms. Journal of Psychosomatic Research, 37, 195-202. Bitzer, J. (2005). Belara - proven benefits in daily practice. The European Journal of Contraception and Reproductive Health Care, 10(supplement 1), 19-25. Casper, R. F., Hearn, M. T. (1990). The effect of hysterectomy and bilateral oophorectomy in women with severe premenstrual syndrome. American Journal of Obstetrics and Gynecology, 162, 105-109. Freeman, E. W., Kroll, R., Rapkin, A., Pearstein, T., Brown, C., Parsey, K., Zhang, P., Patel, H., & Foegh, M. (2001). Evaluation of a unique oral contraceptive in the treatment of premenstrual dysphoric disorder. Journal of Women’s Health & Gender Based Medicine, 10, 6, 561-569. George, L, (2005). The end of menstruation. Maclean’s, 118, 50, 40-46.
9
PMS and OCs 10 Graham, C. A., & Sherwin, B. B. (1992). A prospective treatment study of premenstrual symptoms using a triphasic oral contraceptive. Journal of Psychosomatic Research, 36, 257-266. Hamarback, S., & Backstrom, T. (1988). Induced anovulation as treatment of premenstrual tension syndrome: A double-blind cross-over study with GnRH-agonist versus placebo. Acta Obstet Gynecol Scandinavia, 67, 159-166. Hatcher, R. A. (2004). Contraceptive technology (18th ed.) San Francisco, CA:Ardent Media Inc. Huddleston, M., & Jackson, E. A. (2001). Is an extract of the fruit of agnus castus (chaste tree or chasteberry) effective for prevention of symptoms of premenstrual syndrome (PMS)? The Journal of Family Practice, 50, 4, 298-298. Jones, R. E., & Lopez, K. H. (2006). Human reproductive biology (3rd ed.) San Diego, CA: Academic Press. Kouri, E. M., Halbreich, U. (1997). State and trait serotonergic abnormalities in women with dysphoric premenstrual syndromes. Psychopharmacological Bulletin, 33, 767 770. London, R. S., & Bradley, L. (1991). Effect of a nutritional supplement on premenstrual symptomatology in women with premenstrual syndrome: A double-blind longitudinal study. Journal of the American College of Nutrition, 10, 494-494. Mezrow, G., Shoupe, D., Spicer, D., Lobo, R., Leung, R., & Pike, M. (1994). Depot leuprolide acetate with estrogen and progestin add-back for long-term treatment of premenstrual syndrome. Fertility and Sterility, 62, 932-932. Mortola, J. F., Girton, L., & Fischer, U. (1991). Successful treatment of severe
PMS and OCs 11 premenstrual syndrome by combined use of gonadotropin-releasing hormone agonist and estrogen/progestin. Journal of Clinical Endocrinol Metab, 72, 252 A-F. Schellenberg, R. (2001). Treatment for the premenstrual syndrome with agnus castus fruit extract: Prospective, randomized, placebo controlled study. BMJ, 322, 134-137. Sveinsdottir, H., & Backstrom, T. (2000). Menstrual cycle symptom variation in a community sample of women using and not using oral contraceptives. Acta Obstetricia et Gynecologica Scandinavica, 79, 9, 757-764.