Contraception (Birth Control) and Family Planning PubHealthInfo

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PubHealth.info® (a subsidiary of PakMed) presents scientific information mainly based on abstracts of articles published on a variety of public health issues/topics, particularly encompassing population planning, disease prevention, maternal and child health, and communicable and non-communicable diseases (like HIV AIDS, malaria, etc) that are affecting a significant portion of population in developing and developed countries. Here you can find abstracts of articles published on a variety of public health topics under category "Contraception (Birth Control) and Family Planning". Contraception (birth control) is a regimen of one or more actions, devices, or medications followed in order to deliberately prevent or reduce the likelihood of a woman becoming pregnant or giving birth. Therefore contraception is the utilization of various and sundry surgical procedures, devices, practices, agents, or drugs with the intention of preventing conception or impregnation (pregnancy). Methods and intentions typically termed birth control may be considered a pivotal ingredient to family planning. Birth control is a controversial political and ethical issue in many cultures and religions, and although it is generally less controversial than abortion specifically.

YEAR: 1983

CATEGORY: Contraception (Birth Control) and Family Planning

TITLE

Poly(lactic acid) and poly(lactic acid-co-glycolic acid) contraceptive

delivery systems.

AUTHORS

Beck LR; Tice TR

SOURCE

In: Mishell DR Jr, ed. Long-acting steroid contraception. New York, Raven Press,

1983. :175-99. Advances in Human Fertility and Reproductive Endocrinology

ABSTRACT

The scope of this chapter is limited to a specific class of biodegradable contraceptive systems that use

homopolymers and copolymers of poly(lactic acid),(PLA) and poly(glycolic), (PGA) acid as the polymeric platform or

matrix for the controlled delivery of contraceptive steroids. Discussion reviews the properties of PLA, PGA, and their

copolymers; in vitro studies; and in vivo studies. The homopolymers, PLA and PGA, also referred to as polylactide

and polyglycolide, and copolymers thereof, poly(lactide-co-glycolide) (PLGA), are thermoplastic, biodegradable

materials that are suitable for surgical implants. 1 of their earliest applications was for resorbable sutures. In the

area of controlled release, PLA and PLGA are used as rate controlling membranes and erodible polymeric excipients

for implantable drug delivery systems. In this application these materials show considerable promise in providing

efficacious pharmaceutical formulations. The combination of these polymers with contraceptive steroids in the form

of tablets, films, and cylinders to achieve controlled delivery of drug has been studied. Their use as excipients for

the delivery of contraceptive steroids is somewhat limited if the release of drug is to be controlled solely by a

diffusional mechanism. This is because PLA, PGA, and PLGA are glassy rather than rubbery materials. Because of

this morphology, they are relatively impermeable to steroids. Due to the complexities of biodegradation of PLA and

PLGA, devices containing these materials should be tested to determine their specific reabsorption rates. For

example, the rate of biodegradation of norethisterone (NET) microcapsules having d1-PLA and d1-PLGA excipients

with 0-25 mol% glycolide was determined in rats. Evaluation of the biodegradation curves obtained from unsterilized

microcapsule formulations reveals that increasing the quantity of glycolide in the copolymer excipient causes a

corresponding increase in the rate of biodegradation of the microcapsules. Various in vitro methods have been used

to evaluate controlled release contraceptive steroid systems. A simple and rapid in vitro model was devised to

guide the process development and optimization of the NET microcapsule systems. This in vitro release study was

performed by weighing out in triplicate about 10 mg quantities of 25% loaded NET microcapsules and placing each

sample in an 8 ounce bottle containing 100 ml of 27.5 wt% aqueous ethanol. The amount of NET accumulation in

the receiving fluid as a function of time was determined spectrophotometrically at 247 mm. The method can be used

to predict in a relative manner the duration of release in vivo once 1 batch of microcapsules has been tested in vitro

and in vivo. (PubHealth.info Document ID: CONT5T 2082-06)

PubHealth.info NOTE: The author(s) of this article titled, "Poly(lactic acid) and poly(lactic acid-co-glycolic acid)

contraceptive delivery systems.", is(are) Beck LR; Tice TR. The source of this article is "In: Mishell DR Jr, ed.

Long-acting steroid contraception. New York, Raven Press, 1983. :175-99. Advances in Human Fertility and

Reproductive Endocrinology Volume 2". This article was published in 1983 in English language(s). (PubHealth.info®

Document ID: CONT5T 2082-06. All rights reserved with PubHealth.info) PIN: 22082

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