Natural Contraception

Written By: Sam Savage

Published Date: October 23, 2005 Last Edited: October 23, 2005

By Breuner, Cora Collette

Among consumers and health professionals, complementary and alternative medicine (CAM) has become sought after and integrated into mainstream provision of medical services. CAM, known as nonallopathic, unconventional, holistic, or natural therapy, encompasses many types of healing practices [1,2] From the Cochrane Collaboration, CAM is a “a broad domain of healing resources that encompasses all health systems, modalities, and practices and their accompanying theories and beliefs, other than those intrinsic to the politically dominant health systems in a particular society or culture in a given historical period” [3].

A 1993 Harvard study documented that in 1990, more than one- third of Americans used unconventional therapies [4]. In a second study, this number increased by 38%, from 60 million to 83 million people per year between 1990 and 1997. Expenditures for visits to alternative medicine providers were estimated at $21.2 billion, $12.2 billion of which was paid out-of-pocket. Nearly one in five individuals taking prescription medicines also was taking herbs or highdose vitamin supplements [5]. CAM use is considerably higher in specific groups of children and adolescents, such as in those with cystic fibrosis, cancer, arthritis, and in those undergoing surgery [6-12]. Use in homeless adolescents was noted to be 70% and was felt to be caused, among other things, by a need to use something natural and a mistrust of mainstream health care. These youth faced medical and mental health illness on an acute and chronic basis yet felt more confidence in a system that embraces CAM [13]. From a Detroit study, 12% of the pediatrie patients were using CAM [14]. A significant predictor for CAM use in the pediatrie populations is the use of CAM by parents.

Primary care providers are resources for advice and recommendations about using CAM. Adult primary care providers maintain an open attitude toward CAM and may make referrals to CAM providers, or use CAM themselves [15-21]. Similar findings were seen within a study of pediatricians [22].

There are multiple effective contraceptive medical allopathic choices available for women and men in the form of the birth control pill, injectables, barrier methods, intrauterine devices, and sterilization. Yet these may not be the only options that people use, as made clear from studies on CAM use. The contracepting community, of which adolescents may be active or passive members, includes those who seek alternative choices for many chronic illnesses, for prevention or health maintenance, and as an adjunct to the medical services provided by allopathic providers. This article discusses some of these options for contraception, including natural family planning and plant- derived hormonal contraception. The discussion will include medical evidence to support or refute these methods, potential dangers of these interventions, and additional resources for those who want to learn more.

Natural family planning-historical view

The concept of regulating fertility is not a new one. The decline in fertility among the white middle class was noted in Europe and then the United States in the 19th century [23]. The gospel of self sovereignty and fewer children and healthy, happy maternity was coincident with reproductive control and drew considerable support around the time of the Civil War. Fertile times, when sexual activity needed to be curtailed, were documented in diaries and in the medical literature and were discussed at length in the higher social circles.

Family planning has belonged to a highly discordant and not necessarily peaceable clan [24,25]. Family planning to many has been the cornerstone of feminism, redefining the role of women from their patriarchal-defined role as child bearers and household managers. For others, the term is synonymous with abortion. The criminalization of abortion during the latter half of the 19th century drove reproductive services and dissemination of information underground until the middle of the 20th century. Only recently has it become apparent that discussion of contraception is less of a taboo and more of an ethical right for women and men.

From the historical perspective in island and native cultures, sexual taboos against premarital and adolescent sexual union did not exist, as observed and recorded by anthropologists. One reviewer noted that in these cultures where sexual experimentation among adolescents was allowed, there was a general absence of pregnancy [26], Ethnographic reports are highlighted in the next section.

Regarding the Triobriand islanders in Oceania

Since there is so much sexual freedom, must there not be a great number of children bom out of wedlock? If this is not so, what means of prevention do the natives employ? .. .it is very remarkable to note that illegitimate children are rare. The girls seem to remain sterile throughout their period of license.. .until they marry; when they are married they conceive and breed sometimes quite prolifically.. .1 was able to find roughly a dozen illegitimate children recorded genealogically throughout Triobriands, or about 1 %. Thus we are faced with the questions: why are there so few illegitimate children? .. .they never practice coitus interruptus [27].

In the textbook Medical History of Contraception, Himes postulated that desire for contraception is a universal social phenomenon; every society possesses some knowledge of birth control, even if the methods are not always effective. Ethnographers in the era along with Himes rejected the idea of medicinal plants, roots, and barks as commonly used contraceptives. Female researchers who visited these cultures, however, were able to establish trust with the native women in Peru, the Pacific islands, and the Pacific Northwest Native American Shoshone and learned of contraceptive plants grown in small secret gardens and used by these indigenous women.

The questions from the past remain pertinent today. Women want to know: when am I the most fertile? When am I the least fertile? And for adolescents, what is the perfect (easiest) way to keep from getting pregnant? (tonight)? For many, natural birth control answers these questions and helps women to be more in control of their fertility.

In the United States, approximately 4% of women of reproductive age use natural family planning (NFP) to avoid pregnancy. In one study, a questionnaire was mailed to 1500 women, aged 18 to 50 in Missouri in 1992. Almost 25% stated that they would probably use NFP in the future to avoid pregnancy, and 37.4% indicated that they would likely use NFP in the future to become pregnant [28]. A woman’s decision regarding her desires for a family are planted well before her actual first pregnancy, most likely during her adolescent years [29]. Women are seeking out information on natural birth control as a method to prevent pregnancy [30],

Can adolescents learn information needed for natural family planning?

The correspondence of cervical mucorrhea with elevated concentrations of serum and 24-hour urinary estrogens has been established [31-33]. Can this information be disseminated to the adolescent population? Many would think that this is a concept far from the grasp of an adolescent. Yet Klaus and Martin evaluated this and concluded that ethnically and socioeconomically diverse perimenarchal girls can be taught to recognize their cervical mucus patterns and distinguish anovulatory from ovulatory cycles [34].

Young women can take an interest in the physiology of their own bodies. In a study on the pathophysiology of polycystic ovarian syndrome, women performed menstrual charting in an attempt to understand ovulatory disorders. Although this article focused on polycystic ovary syndrome and hypothalamic dysfunction, information gained from a paper such as this can be used in future research on the reproductive health education of the young woman. With knowledge of fertility and menstrual cycle function, adolescents and young women are in a stronger position to make informed decisions about how they wish to manage their reproductive and sexual health [35].

Fig. 1. Marquette model chart. Most commonly patients color code the interpretation: red for menses, green for infertile day, blue for fertile day. The amount of flow is also described is the space allotted for comments. This chart represents a luteal phase deficiency. Note the shortened luteal phase of only 8 days. (From: Barron ML. Proactive management of menstrual cycle abnormalities in young women. J Perinat Neonat Nurs 2004; 18(2):81-92.)

There are many types of NFP, including the Billings Method (the ovulation or mucous method), named for Australian doctors Jon and Evelyn Billings. This method charts the presence and description of cervical fluid [36]. The mucous method describes three different cervical fluids during the menstrual cycle: (1) sticky, tacky, and dry occurring after menstruation, (2) creamy, milky, and smooth, which occurs right before the most fertile period, which is (3) slippery, egg white, stretchable, clear, and yellow /pink or red tinged. Women are taught to avoid intravaginal sexual activity when the cervical mucous reflects the most fertile time [37]. An example of this method is noted in Fig. 1.

Herbal contraception

Herbal products historically have been the cornerstone of much of the pharmaceutical armamentarium. Active segments of the plant include leaves, flowers, stems, roots, se\eds, and berries. Plant- derived products used by health care providers include the statins, which are derived from the fungus Aspergillus terreus; cephalosporins, derived from a marine fungus (Cephalosporium acremonium); digoxin from foxglove (Digitalis lanata), progesterone (Dioscorea villosa, Mexican yam); and cromolyn sodium, a khellin derivative from the Ayurvedic herb Ammi visnaga [38].

From the Harvard studies on CAM use in 1990 and 1997, the use of selfprescribed herbal remedies within the United States increased from 2.5% to 12.1% [4,5]. The proportion of individuals consulting practitioners of herbal medicine rose from 10.2% to 15.1%, and they spent around $5 billion on herbal medicines. In 1998, Brevoort estimated the total retail sales of herbal medicines close to $4 billion [39].

Experts in the field of naturopathy and medicine do not support herbal contraception because of the lack of scientific evidence of efficacy and the possibility of adverse outcomes. With that in mind, it is known that the plant kingdom contains numerous bioactive substances that may affect the regulation of reproduction. Many herbs have been used to reduce fertility with little or no scientific evidence supporting this claim [4O]. Berman, an expert in CAM, does not recommend contraceptive herbs in that they may be abortifacients that work by poisoning the woman [41]. Fifty-seven poisonings from attempts at herbal abortion, including two deaths, were reported in a 1900 to 1997 review [42]. The German Commission E Monographs issued repeated warnings that many herbs can cause pregnancy termination as a side effect and so are not recommended in the pregnant patient or in one desiring pregnancy [43]. Importantly, many of these herbal supplements may be substandard both in content of active constituents and in lack of contamination. Health professionals need to educate their patients on the lack of stringent federal regulation of these products. There have been recent attempts at improving the standards [44,45].

The following herbs and other compounds have been evaluated predominantly in the laboratory with mixed results. If available, information on typical doses is cited. Techniques used for extraction of the bioactive ingredients of these herbs are noted to use ethanol or methanol, which may cause some of the anticontraceptive effects. Except for the isolated occasion, many of these herbs have not been studied in people. Despite this, usage may be higher in women and men than previously thought judging by the high volume of people accessing herbal contraception on the Internet (eg, www.sisterzeus.com). It is not known how many adolescents use these products.

Ovulation inhibition, anti-implantation

Queen Anne’s lace seeds/Wild carrot fDaucus carotaj

Women have used seeds from Daucus carota for centuries; the earliest written references dates back to the late 5th century BC appearing in a work written by Hippocrates. Many view Queen Anne’s lace as a promising postcoital agent, and Internet discussion recommends use similar to emergency contraception, although there has been little or no scientific evidence to support this claim. Typically, one teaspoon of the seeds are chewed and then swallowed with water or juice. The claim is that the volatile oils from the seeds prevent implantation, and thus the seeds must be chewed before swallowing [46].

Stem bark extracts

Multiple studies on the stem bark extracts of Combretodendron macrocarpum, Cola nitida, Afrormosia laxiflora, and Pterocarpus erinaceus have shown that they block the estrus cycle of female rats. It is thought that these compounds may bind to steroid receptor sites with resultant antigonadotropic activity. The most potent competitor for steroid receptors was C macrocarpum extract, followed by P erinaceus, C nitida and A laxiflora [47-49].

Rivea plant (llivea hypocrateriformisj

The plant Rivea hypocrateriformis was tested for anti- implantation effects and as an abortifacient in female rats using petroleum ether, chloroform, ethanol, and distilled water extracts. The ethanol extract was found to be most effective in causing significant anti-implantation and interruption of early pregnancy. The active ethanol extract contained alkaloids, glycosides, saponins, tannins, and phenolic compounds. Whether the contraceptive effects of this plant are caused by the constituents of the extract or an active ingredient of the plant is unclear [5O].

Castor plant (Hicinus communis,)

This plant is a native of India with 17 species that produce large seeds containing the active constituent ricin, a glycoprotein. The castor oil from the seed has been used as a purgative and traditionally is accepted as a contraceptive by women throughout India and Africa. Ricin also is found in smartweed leaves (Polygonum hydropiper). In a study looking at mechanism of action of this compound, female laboratory animals were injected with ricin, placed in cages with males of the same species and then had laparotomies looking for fetus implantation. Controls were injected with estradiol. The findings from this study indicated that Ricinus communis might possess estrogenic and anti-implantation activity [51].

Contraception was evaluated in people using the seeds of Ricinus communis (RICOM-1013-J) in two separate studies. In both trials, women were given one single oral dose of 2.3 to 2.5 g. No pregnancies were detected in subjects for 1 year in one study and for 8 months in the second study. Adverse effects included headache, nausea, vomiting, weight gain, loss of appetite, increased blood pressure, and dysmenorrhea. The results of the liver and renal function profiles in women volunteers showed that there were no significant (P

Wild yam (Dioscorea villosa)

It has been hypothesized that wild yam contains dehydroepiandrosterone-like properties and may act as a precursor to estrogen and progesterone. In the 196Os, progesterone, androgens, and cortisone were chemically manufactured from Mexican wild yam, and this has led many to believe consumption of this plant can lead to the same chemical conversion in the human body. It is used for dysmenorrhea and as an alternative to hormone replacement therapy to treat the symptoms of menopause [56]. It is not recommended as a contraceptive agent [57].

Marshmallow plant (Malvaviscus conzattii,)

The methanol extract of the flowers of Malvaviscus conzattii was administered to rats orally and was found to be effective in inhibiting ovulation. From these data, the researchers suggested that there might be an interference with the synthesis or release of gonadotropins from the pituitary gland [58].

Asparagus (Asparagus pubescens,)

The methanolic extract of Asparagus pubescens root was investigated for its contraceptive activity in mice, rats, and rabbits. Fetal implantation was inhibited in a dose-dependent manner [59].

Other herbs

In India, many antifertility herbs are used by indigenous peoples living in the hills (Drynaria quercifolia) [6O]. Ayurvedic traditional herbs are used by those in more urban environments (Pippaliyadi vati, Molluga stricto, Ruta graveolens, Derris brevipes variety coriace). Studies are preliminary on mechanism of action and efficacy of these herbs [61-64]. In one laboratory study using Ferula jaeschkeana, uterine implantation was inhibited by ingesting an extract of this herb [65]. Similar studies of Ethiopian indigenous medicinal plants traditionally used as antifertility agents appear in the literature [66].

Abortifacient

Every indigenous pharmacopeia contains some type of herbal abortifacient, and these plant products are among the oldest of herbal medicines. Anecdotal evidence suggests that use of herbal abortifacients declines when safe, legal, and affordable clinical abortion and contraception is available.

Pennyroyal (Hedoema pulegiodes)

Pennyroyal traditionally has been used as an abortifacient, yet its toxicity is well documented [67,68]. Doses required for abortion can cause irreversible kidney damage, hepatic disease, and death. It is not recommended and is considered unsafe by Natural Medicine Comprehensive Database.

In a retrospective study of 86 cases of herbal infusion ingestion with abortive intent reported to the Poison Control Center Uruguay between 1986 and 1999, 35 plant names representing 30 species were used. Most frequently used were rue (ruda; Ruta graveolens), cola de quirquincho (Lycopodium saururus), a type of parsley (Petroselinum hortense), and an over-the-counter herbal product called Carachipita, which contains pennyroyal (Mentha pulegium), yerba de la perdiz (Margiricarpus pinnatus), oregano (Origanum vulgre), and guaycuru (Statice brasiliensis). In 23 cases, patients ingested homemade brews made from two to six different species. Rue and parsley were among the more successful abortion agents; they were also among those producing the most toxic symptoms [69].

Spermicidal

Sedum praealtum

Intravaginal ethanol extracts of Sedum praealtum in mice decrease spermatozoa viability for 24 hours after administration [7O].

Cotton plant (Gossypium hirsutum)

Gossypol has been studied in women as an effective spermicide and has been found to immobilize spermatozoa when inserted intr\avaginally. It also has been shown to have an inhibitory effect on herpes simplex virus in vitro [71].

Neem oil (Azardirachta indica)

Neem oil pressed from the bark of Azardirachta indica, a native Indian plant, is considered a spermicidal agent when used intravaginally. It also has antimicrobial and antifungal properties [72]. Orally, neem oil caused arrest of spermatogenesis in male rats along with a decrease in sperm motility and density [73]. Intrauterine neem oil administered to rats and monkeys caused a block in fetal implantation [74].

Zinc acetate and Aloe barbadensis

In a study using 20 samples of fresh ejaculate from volunteers (age 20 to 30 years), zinc acetate was noted to be spermicidal. Lyophilized Aloe barbadensis also was noted to be spermicidal because of the spermatozoa tail toxicity from multiple elements present in small amounts (boron, barium, calcium, chromium, copper, iron, potassium, magnesium, manganese, phosphorus, and zinc). In the laboratory animal, these compounds did not irritate the vaginal epithelium. It was suggested that zinc acetate and lyophilized Aloe barbadensis warranted further study as a vaginal contraceptive [75].

Male antifertility herbs

Cotton plant (Gossypium hirsutum)

Gossypol (Gossypium hirsutum) is a polyphenolic extract of the seed of the cotton plant, and, when taken orally, it may suppress sperm concentration by inhibiting spermatogenesis [76,77]. Gossypol can cause fatigue, hypokalemia, persistent oligospermia. and can interfere with digoxin or other diuretics. It typically is taken as 15-20 mg/d [78].

Papaya (Carica papaya,)

Papaya has been used as a male contraceptive. In adult male rabbits receiving an aqueous extract of papaya seeds orally, no contraceptive effects were noted contrary to the observations made in previous studies [79].

Piperine

Piperine has been used as an oral male contraceptive agent. Histological studies in male rats receiving piperine revealed a partial degeneration of germ cell types, damage to the seminiferous tubule, decrease in seminiferous tubular and Leydig cell nuclear diameter, and desquamation of spermatocytes and spermatids. A 10 mg dose of piperine caused a marked increase in serum gonadotropins and a decrease in intratesticular testosterone concentration. The clinical implications of this study are unclear [8O].

Nicotine

Nicotine causes a reduction in the weight of epididymis and vas deferens in rat studies. The clinical implications of this finding are unclear [81].

Thunder god vine (Lei Gong Teng,)

Thunder god vine has been used for rheumatoid arthritis, menorrhagia, multiple sclerosis, and as a male contraceptive. There is insufficient evidence of efficacy for use as a male contraceptive, but it is postulated that in thunder god leaf and root, the triptolide and tripdiolide inhibit sperm transformation, maturation, and motility. Fertility may return to normal 6 weeks after cessation of use. Adverse effects include gastrointestinal upset, diarrhea, headache, hair loss, and immunosuppression [82].

Tripterygium hypoglaucum

Tripterygium hypoglaucum is a plant used in southern China for renal, liver, skin, and rheumatoid diseases. It also is considered a male antifertility herb. In 24 males aged 20 to 43 years who were given a daily concoction for 2 to 48 months, sperm motility and concentration were lower than in control subjects. These sperm changes were reversed 6 to 12 months after cessation of treatment. Follicle-stimulating hormone, luteinizing hormone, testosterone levels, and libido were similar in treated and control groups [83].

Solanum xanthocarpum

Solarium xanthocarpum is being studied in the laboratory in India as an inhibitor of spermatogenesis [84].

Anacardium occidentale

β-sitosterol, a phytosterol isolated from the leaves of Anacardium occidentale, can cause estrogenic effects and reduce the number of implantation sites in rabbits [85]. It also can inhibit the process of spermatogenesis in male rats [86]. Two doses were studied in rats for 16, 32, and 48 days. High-dose treatment reduced sperm concentration and weights of testis. Further studies were recommended [87].

Summary

The field of CAM is broad and diverse [88-9O]. CAM therapies may be viewed as an adjunct to conventional treatment or as a primary source of medical service [91,92]. Understanding patient choices, and supporting them if safe, reflect respect for the health care choices made by patients [93]. Health care providers must be aware of the safety and efficacy of alternative treatments and know how to access resources to help guide the patient methodically through a decision tree on CAM use for contraception.

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