May 2008
Volume 3, Issue 5

From folk remedy to contraceptive product formulation: Papaya seed extract

Though a growing portion of worldwide contraceptive research is being done in China and India, it can be difficult to get information on those studies, particularly if the results are published in a non-English journal. This month we begin a series on male contraceptive leads beyond the US borders, beginning with Carica papaya extracts, under study by Prof. N.K. Lohiya of Jaipur, India. (We have edited his responses to simplify or explain technical terms.)

Papaya seeds

Originally native to Latin America, the papaya is now cultivated in most countries with tropical climates. The fruit is widely used for food. The plant produces a latex sap rich in the enzyme papain, a protease that tenderiz es meat and other proteins. Both the green fruit and the sap have multiple additional medicinal uses, including folk remedies for contraception and induced abortion. Medical research in adult male langur monkeys has confirmed the contraceptive capabilities of papaya.

Q: How does it work as a male contraceptive?

Prof. Lohiya: The seeds of ripe papaya have been investigated for the control of male fertility in rats, rabbits and langur monkeys. The extracts, when given by mouth, at different doses, cause infertility in animals by either stopping the sperms' motility (ability to swim) or stopping sperm production in the testis. The contraceptive effects are reversible following withdrawal of the treatment, and the animals did not show toxic symptoms.

Q: What is the next step in this research?

Prof. Lohiya: We have established the contraceptive potential of the seed products of Carica papaya in all three animal models tested. Safety of the [drug] has also been investigated by tests of short-term and long-term use in animals, and carcinogenicity tests (tests to make sure it does not cause cancer). Developmental toxicity and teratogenic potential of the drug are in progress. [These studies will assure safety in future generations.] However, in plant research, identification of the active ingredient of the test material is essential for mass production and for reproducibility of the results. Our current research is focused on identifying the active [chemical compounds].

Q: What is your biggest hurdle or concern?

Prof. Lohiya: One of the major hurdles in plant research is the reproducibility of the results. What seems to be the same plant that has shown to be effective in folk remedies and centuries of practice, may not be effective in animal models. In many cases, the results vary from no activity to 100% activity with the same plant. Proper recording of time and place of collection, proper authentification of plants, uniform procedures for extraction, and other studies may help in identifying the plant products with fertility regulation properties [the active ingredient].

Q: What other contraceptive research areas are you working on?

Prof. Lohiya: We successfully showed azoospermia [no sperm] and then reversal to normal functional sperm in RISUG-injected langur monkeys. An exploratory feasibility trial of a male spacing method in langur monkeys by repeated vas occlusion and non-invasive reversal has also been successfully demonstrated by us for the first time in male contraceptive research. The procedure may offer the feasibility of total non-invasive reversible vas occlusion by no scalpel injection and non-invasive reversal. We're awaiting clearance from the relevant drug regulatory agencies to try this reversal procedure in humans. We are also currently investigating safety in two generations of animals following RISUG reversal with DMSO or sodium bicarbonate (a baking soda solution).

Q: What would most help your contraceptive research move forward?

Prof. Lohiya: Technical, infrastructural, and financial inputs would help us to characterize the seed products and would facilitate our efforts towards developing a contraceptive pill of plant origin.

Return to the top

Worldwide need for improved contraceptive options

Citizens of both developed and developing countries have a need for new family planning options, and emerging male contraceptives will be an important piece of improved global reproductive health. A series of recent research publications provide the statistics to back up the assertion of a global need for improved contraceptives.

The Guttmacher Institute found that 3.1 million unplanned pregnancies occur yearly in the US. Method failure accounted for almost half of the unplanned pregnancies. Forty-three percent of those pregnancies occured in women whose contraceptive use was inconsistent or incorrect, while 5% “were in women whose contraceptive method was used correctly but failed.” There is room for improvement in method counseling and use — and in the range of methods available.

The need for better family planning options among adolescent women and men is global. United Nations’ statistics on global fertility trends show that adolescent birth rates in developed countries range “between 4.9 and 43.0 births per 1000 women aged 15-19,” with a much wider range of 2.2 to 200.1 births per 1000 adolescent women in developing countries. While the US has an anomolously high rate of 43 adolescent births per 1000, a recent drop this rate shows change is possible. The majority of this decline is attributed to increased use of contraception.

Among couples of all ages, the Population Reference Bureau projects that demand for contraception will grow in the coming years. Their new data chalks up this increasing demand to “two trends: the burgeoning numbers of young people entering childbearing age and the increasing adoption of contraceptive use.” These trends are acting at different rates in various regions, and the resultant growth in demand “will be especially strong in some countries.”

All of this research shows the importance of family planning in meeting the reproductive health needs of couples in all countries.

Read more:
 • Guttmacher Insititute’s Improving Contraceptive Use In the United States
 • BMJ’s “Problems with contraception play big part in unplanned pregnancies, study says
 • United NationsWorld Fertility Patterns
 • Population Reference Bureau’s Family Planning Worldwide

Return to the top

Male Health Educator Training Institute coming up!

The Office of Family Planning is sponsoring the Male Health Educator Training Institute in Albuquerque, New Mexico, from July 20-25th. “The Male Health Educator Training Institute is an annual intensive week-long seminar sponsored by Title X to support our continuing commitment to male reproductive health. It is designed to provide health educators with comprehensive knowledge of reproductive health, family planning and basic health education competencies to enable them to work more effectively with male clients in family planning programs and clinics.” Modules include sexual development, family planning, communication, fatherhood, intimate partner violence, and health education applications. Dr. David Bell, Medical Director of Columbia University Medical Center ’s Young Men's Clinic, will teach a special module “Anatomy, Contraception and Sexually Transmitted Diseases 101”. Eligible health educators work directly with male clients at least half the time. The National Training Center for Family Planning pays for a hotel room and provides a per diem.

Return to the top

Male contraceptives in the press

On the occasion of an Australian engineer announcing his idea for a radio-controlled sperm blocker, the June issue of Popular Science includes a brief piece on several other non-hormonal male contraceptives in the works — all of which are reality, not just a concept. “The idea is to stop sperm at one localized site, rather than using hormones that can affect heart function, weight and cholesterol levels,’ reports Cliff Kuang, who picks clever nicknames and eye-catching graphics to describe RISUG (“Drano”), the IVD, and ultrasound (“contraception could become a twice-yearly checkup procedure, like going to the dentist”).
Beyond the Male “Pill”: From remote-control key fobs to ultrasound, male contraception goes high tech
Popular Science, June 2008

The Los Angeles Times covers the hormonal research meta-analysis by UCLA team Drs. Ron Swerdloff and Christina Wang, and asks men to weigh in with their opinion. “‘The concept has been validated,’ says Swerdloff. ‘We are convinced that new alternatives for family planning are needed. But a product is not yet ready to go to market.’ Why not? Perhaps pharmaceutical companies are on the sidelines because they don't think men are enthusiastic about controlling their own fertility. What do you say, men?”
Male contraception almost ready. Are men?
Los Angeles Times, 1 May

Additional Southern California papers profile Drs. Wang and Swerdloff. “A study compiled by two Torrance-area scientists — a married couple who head one of only two government-funded research centers in the United States for male contraceptives -- found that hormone pills that block sperm production in men are safe and reversible. ‘There is more of an awareness that the responsibility in family planning should be a shared responsibility…’”
Local experts tout male birth control
Daily Breeze, 29 April

Oklahoma newspapers feature Oklahoma Medical Research Foundation scientist Dr. Kevin Moore and his knockout work on two closely-related enzymes, tyrosylprotein sulfotransferases (TPST) 1 and 2. Mice lacking the TPST-2 enzyme are infertile due to impaired sperm-egg binding. “Though promising, Moore’s male contraceptive is years from human testing. He has started a new drug discovery company called Siwa Biotech Corporation and has begun searching for a compound to inhibit the production of TPST-2. He said that his team has narrowed thousands of contenders to about 150 possible options and that he may be able to narrow those down to a good candidate by next week.”
City research may lead to ‘the pill’ for men, 29 April

Journalist Amy Crawford writes a well-researched piece covering the new retinoic acid receptor antagonist research at Columbia University, and clarifying the struggles faced by hormonal researchers — in addition to mentioning suspensories, RISUG, and the IVD. “Though they didn't look like much, the white specks squirming under a microscope in researcher Debra Wolgemuth's lab could have a big impact in the high-stakes world of controlling fertility — not for women, but for men… ‘In the past 30 to 40 years,’ said Lissner, ‘there's been a societal shift in the responsibility men take for reproduction. It takes time for science and money to catch up, so it's only been in the last five to 10 years that this [field] has taken off.’” Written for the Columbia News Service, a wire put out by Columbia Journalism School and the New York Times Company, this article was also syndicated in other papers around the country.
Scientists say male contraceptive is closer than ever
Vermont Sunday Magazine, 18 May

College papers continue to cover male contraception and interview students to guage their interest in new methods. “The responsibility of birth control has fallen on females since its invention. But a range of birth control methods now being tested suggest that society is putting more responsibility on males when it comes to using protection…”
Birth control everyone's responsibility
OSU - The Lantern, 15 May

Return to the top

Calendar of events

MCC Director Kirsten Thompson will be presenting a poster of recent findings on men's interest in emerging male contraceptives at the September ARHP conference. If you plan to attend, come say hello!

June 9-15
International Men’s Health week
July 20-25
Male Health Educator Training Institute; Albuquerque, NM, USA
September 15
Deadline for Asia-Pacific Council on Contraception abstract submission
September 17-20
Association of Reproductive Health Professionals' Reproductive Health 2008; Washington, DC, USA
September 26
World Contraception Day
October 25-28
2008 American Public Health Association Annual Meeting & Exposition; San Diego, CA, USA
December 4-6
Second Congress of the Asia-Pacific Council on Contraception (APCOC); Macao, China

Return to the top


Elaine Lissner, Director of the Male Contraception Information Project (MCIP)
MCIP is entirely nonprofit and works in three areas: raising public awareness of promising nonhormonal male contraceptives, advocating increased and expedited government research, and serving as a resource for journalists who wish to write about the subject.

Kirsten Thompson, Director of the Male Contraception Coalition (MCC)
The Coalition’s objectives are to speed the development of new male contraceptives through increased legislative and institutional support, to raise funds for applied male contraception research and development, and to educate the public about the work of the research community.