Antifertility

Thiirane is more bactericidal than oxirane, and derivatives of 2-mei captomethylthiirane inhibit tuberculosis. The following pharmacological uses have been reported for compounds derived from thiirane derivatives gold complexes of the adducts of diethylphosphine and thiirane (antiarthritic), adducts of thiiranes and malononitrile (antibacterial, blood vessel dilators, muscle relaxants, sedatives), thermolysis products of thiirane 1-oxides and adducts of thiirane 1-oxides with sulfenyl chlorides (antibacterial), adducts of 2,3-diarylthiirene 1,1-dioxides with ynamines (antibacterial, parasiticidal), adducts of 2,3-diarylthiirene 1,1-dioxides with enamines (antifertility), adducts of p-aminophenylacetic esters with thiirane (immunosuppressants), adducts of amines and thiiranes (radioprotective drugs). 

Dithiazolones, chloro-chlorination, 6, 915 Dithiazolylium salts antifertility activity, 6, 944 as chemosterilants, 6, 944 as herbicides, 6, 944 IR spectra, 6, 907 reduction, 6, 918 Dithiazolylium salts, amino-reactions... 

Harazono, A., M. Ema, and Y. Ogawa. 1998. Evaluation of early embryonic loss induced by tributyltin chloride in rats phase- and dose-dependent antifertility effects. Arch, Environ. Contam. Toxicol. 34 94-99. 

Edwards K, Jackson H, Jones Ar. 1970. Studies with alkylating esters-ll A chemical interpretation through metabolic studies of the antifertility effects of ethylene dimethanesulphonate and ethylene dibromide. Biochem Pharmacol 19 1783-1789. 

Antibiotic revolution has provided long and healthy life to people. The life expectancy has almost doubled. The increased population has caused many social problems in terms of food resources, environmental issues, employment, etc. To control these problems, population is required to be controlled. This has lead to the concept of family planning. Antifertility drugs are of use in this direction. Birth control pills essentially contain a mixture of S)mthetic estrogen and progesterone derivatives. Both of these compounds are hormones. It is known that progesterone suppresses ovulation. Synthetic progesterone derivatives are more potent than... 

The concept of torsional asymmetry is not jnst an interesting abstract idea. Some years ago, fertility in some Chinese rnral commnnities was found to be below normal levels, and this was traced back to the presence of gossypol in dietary cottonseed oil. Gossypol acts as a male contraceptive, altering sperm matnration, spermatozoid motility, and inactivation of sperm enzymes necessary for fertilization. Extensive trials in China have shown the antifertility effect is reversible after stopping the treatment, and it has potential, therefore, as a contraceptive for men. 

The male rat has a large reserve of spermatozoa and it is difficult to detect antifertility effects by using pregnancy as an endpoint. This is because the ejaculate in rats contains over 1000-fold the number of sperm that will produce maximum fertility, in man the multiple is only 2-A times and some studies have suggested that in certain Western populations, average human sperm counts appear to have declined over the past 50 years.The rat s testes are also relatively about 40 times the size of man s, if antifertility effects are observed, it can be helpful to measure various sperm parameters (seminology) to help characterise effects. 

Fertility impairment Medroxyprogesterone acetate at high doses is an antifertility drug. High doses would be expected to impair fertility until the cessation of treatment. 

The roots of Aristolochia indica, commonly known as an Indian birthwort, are reputedly used in Indian folk medicine as an emmenagogue and as an abor-tifacient. Aristolochic acid and its methyl ester, sesquiterpene (12S)-7,12-secoishwaran-12-ol, isolated from this plant, possessed significant antifertility activity in mice (103-105). 

In addition, intraamniotic injection of aristolochic acid I in mid-term pregnant dogs and rats led to termination of pregnancy (106). Later, Che et al. reported that four Aristolochia alkaloids, aristolochic acid I and its methyl ester, aristolic acid, and (125)-7,12-secoish-waran-12-ol were ineffective in antifertility tests, when administered to mice, hamsters, or rats (707). 

The routine developmental toxicity study for vaccines includes dosing of the females before mating and may thus be capable of detecting antifertility effects in the female. There are no requirements to assess effects on male fertility. 

Anti-estrogenic effect. Ethanol (95%) extract of the dried aerial parts, administered intragastric to rats at variable doses was inactive . Petroleum ether extract of the dried leaf, administered intraperitoneally to female rats at a dose equivalent to 10 mg/kg tetrahydrocannabinol (THC) on 11-21 days of age, was active . Antifertility effect. Petroleum ether extract of the entire plant, administered by gastric intubation to female mice at doses of 75 mg/kg and 150 mg/kg, was active. A dose of 3 mg/kg, produced weak activity ". Resin, administered by gastric intubation to male mice at variable dosage levels, was inactive . ... 

K. Srivastava. Antifertility and teratogenic activity of Cannabis sativa in rats. Fitoterapia 1991 62(1) 69-71. 

Gonzalez, F. and M. Silva. A survey of plants with antifertility properties described in the South American folk CN066 medicine. Abstr Princess Congress I Bangkok Thailand 1987 20 pp. 

Antifertility effect. Decoction of the dried seed, administered orally to female adults at a dose of 0.96 L/day, was active. Coffee intake delayed the time to conception and increased relative risk of failure to con-ceive k Decoction of the dried seed. 

DC044 Garg, S. K. Antifertility effect of oil from few indigenous plants on female albino rats. Planta Med 1974 26 391-393. 

DC 169 Chaudhury, R. R. Controversies in the clinical evaluation of antifertility plants. Clinical Pharmacology Therapeutics, P. Turner (ed.), Macmillan, New York, 1980 pp. 474—482. 

Lai, R., M. Gandhi, A. Sankaranara-yanan, V. S. Mathur, and P. L. Pharma. Antifertility effect of Daucus carota seeds in female albino rats. Fitoterapia... 

Singh, M. M., A. Agnihotri, S. N. Garg, S. Agarwal, D. N. Gupta, G. Keshri, and V. P. Kamboj. Antifertility and hormonal properties of certain carotene sesquiterpenes of Ferula jaeschkeana. Planta Med 1988 54(6) 492-494. 

FA093 Keshri, G., V. Lakshmi, M. M. Singh, and V. P. Kamboj. Post-coital antifertility actiivty of Ferula assafoetida extract in female rats. Pharmac Biol 1999 37(4) 273-278. 

Prakash, A. O., and R. Mathur. Screening of Indian plants for antifertility activity. Indian J Exp Biol 1976 14 623-626. 

Ramirez, V. S., L. J. Mostacero, A. E. Garcia, et al. Vegetales Empleados en Medicina Tradicional Norperuana. Banco Agrario del Peru NACL Univ Trujillo, Peru, June 1988 54 pp. Gonzalez, F., and M. Silva A survey of plants with antifertility properties described in the South American folk medicine. Abstr. Princess Congress I Bangkok Thailand 10-13 Dec 1987 20 pp. 

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