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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Glossary

A

Abortion

The expulsion or extraction of the products of conception from the uterus before the embryo or fetus is capable of independent life. Abortions may be spontaneous or induced. Spontaneous abortions are commonly called miscarriages. Induced abortions are voluntary interruptions of pregnancy or therapeutic abortions. Incomplete abortion occurs when some products of conception, usually the placenta, remain inside the uterus. Missed abortion is when the fetus has died in utero and some or all of the nonliving products of conception remain in the uterus.

Abortion, unsafe

A procedure for terminating an unwanted pregnancy either by persons lacking the necessary skills or in an environment lacking the minimal medical standards or both.

Abstinence

Refraining from sexual intercourse.

Adhesion

Abnormal sticking together of body tissues, usually by bands of scar tissue which form between two tissues following inflammation.

Amenorrhea

The absence or suppression of menstruation. This state is normal before puberty, after menopause, and during pregnancy and lactation.

Amenorrheic women

Women who are already pregnant, or who have just had a child and their menses have not yet returned.

Androgen

Generic term for an agent, usually a hormone (e.g., testosterone), that stimulates activity of the accessory male sex organs, encouraging development of male sex characteristics, or prevents changes in the latter that follow castration. Androgens are produced chiefly by the testes but also by the adrenal cortex and the ovary.

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

Anemia

A reduction in the quantity of red blood cells per unit volume of blood to below normal levels.

Antibody

A protein produced by B lymphocytes in response to contact with an antigen from a foreign microorganism and triggered by T lymphocytes. Antibodies attach themselves to the foreign antigen, and to nothing else. This signals other elements of the immune system, including monocytes and macrophages, to destroy the invading organism.

Antigen

1. Any substance capable of reacting with the products of an immune response, that is, specific antibodies, or sensitized T-lymphocytes or both. 2. An extruding molecule on the surface of a cell, microorganism, toxin or other foreign body which is capable, under appropriate conditions, of inducing a specific immune response when coming into contact with a lymphocyte or antibody.

Azoospermia

Absence of living sperm in semen.

B

Barrier method

A contraceptive method that establishes a physical or chemical barrier between the sperm and ovum, e.g., condom, diaphragm, foam, sponge, cervical cap. Some of the barrier contraceptives are used in conjunction with a spermicidal agent.

Biotechnology

The collection of industrial processes that involve the use of biological systems. For some of these industries, the processes involve the use of genetically engineered organisms.

C

Capacitation

The process by which sperm become capable of penetrating an egg, which occurs in the female reproductive tract.

Cervical cap

Small latex or plastic cap that covers the cervix. Users of this barrier method of birth control must spread spermicidal cream or jelly inside the cap.

Chancroid

A sexually transmitted disease caused by the Hemophilus ducreyi bacterium and characterized by a soft sore on the genitals which becomes painful and discharges pus.

Chlamydia trachomatis

A microorganism that can cause vaginitis, urethritis, cervitis, pelvic inflammatory disease, and lymphogranuloma venereum (LGV). Women with positive chlamydia cultures are more likely to have the following: cervical discharge (yellow or green), erythema, ectopy, friability, and white blood cells on microscopic evaluation of cervical secretions. Also called chlamydia, mucopurulent cervicitis, and nongonococcal urethritis (in men).

Coitus

Entry or penetration of the penis into the vagina. Also called intercourse or copulation.

Complication

A difficult factor or issue often appearing suddenly or unexpectedly.

Conception

Generally the beginning of pregnancy. Conception is usually

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

equated with the fertilization of the ovum by the sperm, but is sometimes equated with the implantation of the fertilized ovum in the uterine lining.

Condom

A cylindrical sheath of latex, polyurethane, or sheep intestine worn over the penis during intercourse as a barrier method of contraception and as a prophylactic against sexually transmitted disease. Some condoms contain a spermicide to kill sperm to decrease the risk of pregnancy should a condom break or should semen leak over the outer rim of the condom. Also called a rubber.

Contraception

As a means of logical progression, contraception is necessarily anything that acts against conception, and therefore, anything that prevents the success of fertilization or implantation.

Contraceptive immunogen

All molecular constructs or organoids meant to directly elicit an immune reaction for birth control.

Contraceptive prevalence rate

The percentage of women currently using a contraceptive method.

Contraindications

Describe patients who should not receive a drug because, for one reason or another, the risks of taking it are likely to outweigh the benefits.

Corpus luteum

The structure which develops from the ovarian follicle once a ripened ovum has been expelled. It produces progesterone to prepare the endometrium for implantation. During the second half of the cycle, if conception does not occur, the corpus luteum degenerates, leaving visible scars called the corpora albicans. If pregnancy does occur, the corpus luteum persists and functions through the first half of the pregnancy. During pregnancy it is stimulated by human chorionic gonadotropin (HCG).

Cyst

A walled sac containing gas, liquid, or semi-solid material.

D

Depo-Provera

Injectable form of medroxyprogesterone acetate.

Desired total fertility rate (DTFR)

Hypothesized estimate of what the Total Fertility Rate (TFR) would be in different populations if women were to realize their wishes and bear exactly the number of children they preferred.

Diaphragm

The soft, rubber, dome-shaped device worn over the cervix and used with spermicidal jelly or cream for contraception. Diaphragms are circular, shallow, rubber domes with a firm but flexible outer rim that fit between the posterior vaginal wall (posterior fornix) and the recess behind the pubic arch. Sizes vary from 50 to 105 mm in diameter.

Douche

Cleansing the vaginal canal with a liquid; not an effective means of birth control or STD prevention.

Dysmenorrhea

Painful menstruation. Usually cramping midline lower abdominal pain. May be associated with low back pain, nausea, diarrhea, or upper thigh pain.

E

Ectopic

Out of place; an ectopic pregnancy occurs when the embryo implants

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

outside the uterus, usually in the fallopian tube. Much less commonly, implantation may occur in the endocervical canal, on the ovary, or within the abdominal cavity.

Egg

An ovum; a female gamete; an oocyte; a female reproductive cell at any stage before fertilization.

Ejaculation

Expulsion of semen from the penis.

Endocrine glands

Ductless glands which secrete hormones into the blood-stream.

Endometrium

The mucous inner lining of the uterus.

Epididymis

A coiled tubular structure where sperm cells mature and are nourished, and which connects the testes to the vas deferens.

Estrogen

The primary female hormones; any natural or artificial substance that induces estrogenic activity, more specifically, the hormones estradiol and estrone produced by the ovary. Estrogens are produced chiefly by the ovary but also by the adrenal cortex, the testis, and the placenta.

F

Failure rate

The number of pregnancies occurring per 100 users per year.

Fecund

Potentially fertile.

Fecundity

1 Possessing the power or quality conducive to producing offspring. 2. Exposed to the risk of conception.

Fertility norm

Desired or ideal number of children.

Fetus

The developing conceptus after 7 to 8 weeks postfertilization (the end of the embryonic period) until birth.

Fibrocystic breast disease

Benign breast tumor(s) involving multiple cysts in the terminal ducts and acini of the breast. Believed to be estrogen dependent. Breast cancer is twice as common in women with some types of fibrocystic breast disease. Also known as cystic mastitis, chorionic cystic breast disease, cystic hyperplasia, and cystic adenosis.

Follicle

A small secretory sac or cavity. One type of follicle is an ovarian follicle which is a very small sac in the ovary in which an ovum matures and from which the egg is released.

Follicle stimulating hormone (FSH)

Anterior pituitary hormone which stimulates the ovary to ripen egg follicles. FSH stimulates sperm production in the males testes.

G

Gonadotropin

A substance having an affinity for, or stimulating effect on, the gonads. There are three varieties: anterior pituitary, chorionic (from pregnant women's urine), and equine (from the serum of pregnant horses).

Gonads

An organ that produces sex cells (e.g., the testis and ovary).

Gossypol

A derivative of the cottonseed plant that induces infertility in males; being used experimentally as a male contraceptive in China. Also known to have spermicidal properties when employed as a vaginal contraceptive.

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

H

Homologue

Likeness short of identity in structure or function between parts of different organisms due to evolutionary differentiation from the same or a corresponding part of a remote ancestor.

Hormone

A ''messenger" molecule of the body that helps coordinate the actions of various tissues. Hormones produce a specific effect on the activity of cells remote from their point of origin.

Human chorionic gonadotropin (HCG)

A glycoproteinaceous hormone produced by the placenta which maintains the corpus luteum and causes it to secrete estrogen and progesterone. Measured in urine and blood to detect pregnancy.

Human immunodeficiency virus (HIV)

A virus that causes AIDS. It causes a defect in the body's immune system by invading and then multiplying within white blood cells.

Hypothalamus

Part of the brain just above the pituitary which helps to regulate basic functions such as sleep, appetite, body temperature, fertility. The hypothalamus is influenced by higher cortical levels of the brain and controls hormone production by the pituitary.

I

Immune system

The body's system of protection against infection or penetration by microorganisms, toxins or small particles. Elements of the immune system include white blood cells and the cells, immunoglobin proteins and hormones they produce, such as macrophages, antibodies and lymphokines.

Immunocontraceptive methods

All contraceptive methods based on interference of some step of the reproductive process by products of an immune reaction, be it antibodies or cells.

Immunogen

Any substance that is capable of eliciting an immune response.

Implantation

The process whereby an ovum 6 or 7 days after fertilization burrows into the lining of the uterus and attaches itself firmly. Successful implantation is essential to the development of the embryo.

Infertility

Failure, voluntary or involuntary, to produce offspring. Primary infertility: The woman has never conceived despite cohabitation, exposure to the possibility of pregnancy, and the wish to become pregnancy for at least 12 months (World Health Organization definition). Secondary infertility: The woman has previously conceived but is subsequently unable to conceive despite cohabitation, exposure to the possibility of pregnancy, and the wish to become pregnant for at least 12 months (WHO).

Injectable contraceptives

Hormonal contraceptives given by injection. Two examples of injectable progestins are Depo-Provera (DMPA or depot medroxyprogesterone acetate), and norethindrone enanthate.

Intended pregnancy

One that was wanted at the time, or sooner, irrespective of whether or not contraception was being used.

Interval insertion

All other instances of insertion of the IUD excluding postplacental insertion.

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

Intrauterine device (IUD)

A flexible, usually plastic device inserted into the uterus to prevent pregnancy. May contain metal (generally copper) or hormones for added effectiveness. It produces a local sterile inflammatory response caused by the presence of a foreign body in the uterus which causes lysis of the blastocyst and sperm, and/or the prevention of implantation. IUDs may also prevent fertilization due to deleterious effects on spermatozoa as they pass through the uterus.

K

KAP

Knowledge, attitude and practices

Knockout

Inactivation of a gene.

L

Luteinizing hormone (LH)

Anterior pituitary hormone which causes a follicle to release a ripened ovum and become a corpus luteum. In the male it stimulates testosterone production and the production of sperm cells.

M

Menopause

Cessation of menstruation; i.e., the last episode of physiologic uterine bleeding. After menopause, a woman is naturally infertile. Surgical menopause refers to the removal of a woman's ovaries before natural menopause occurs.

Menses

Menstrual flow.

Microbicide

An agent that inactivates or kills microbes.

Minipill

Oral contraceptive containing no estrogen and generally less than 1 mg of a progestational agent per pill.

Miscarriage

The interruption of the implantation of the embryo in the woman's womb. The fertilized ova that are never implanted and simply lost with the next menstrual cycle are not considered miscarriages or abortions because it is free floating and not being "carried" by the female body.

Mistimed conception

One that was wanted by a woman at some time, but which occurred sooner than wanted.

Myometrium

The muscle layer of the uterus.

O

Oogenesis

Formation and maturation of the egg.

Oral contraceptives (OC)

Various progestin/estrogen or progestin compounds in tablet form taken by mouth; the pill. Estrogenic and progestational agents have contraceptive effects by influencing normal patterns of ovulation, sperm or ovum transport, cervical mucus, implantation, or placental attachment.

Osteoporosis

An abnormal softening, porousness, or reduction in the quantity of bone, resulting in structural fragility. Causes appear to include estrogen deficiency, prolonged immobilization, and adrenal hyperfunction, which result in more bone resorption than formation.

Ovaries

The female gonads; glands where ova are formed; also the primary source of female hormones, estrogen and progesterone.

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

Ovulation

The release of an ovum from the ovarian follicle in the ovary during the female cycle.

Ovum

The egg cell.

Oxytocin

A hormone produced by the pituitary gland. As the baby suckles, impulses are sent to the posterior pituitary. The hormone oxytocin is released causing the milk let-down reflex. Oxytocin also causes the uterine muscles to contract.

P

Pathogen

A microbe capable of causing disease.

Pelvic inflammatory disease (PID)

Inflammation of the pelvic structures, especially the uterus and tubes, whose precipitating or contributing cause quite often is a sexually transmitted disease, e.g., gonorrhea, chlamydia, or both. Also called pelvic infection, polymicrobial pelvic infection, tubal infection, and salpingitis.

Perfect use

When the directions for use of a contraceptive method are followed and the method is used correctly for every act of intercourse.

Perimenopause

Traditionally defined as the few (three to five) years surrounding a woman's last menstrual period; more recently it is being defined as beginning more than a decade before frank menopause, in the mid-thirties and early forties, coincident with the initiation of ovarian decline.

Periodic abstinence methods

Contraceptive methods that rely on timing of intercourse to avoid the ovulatory phase of a woman's menstrual cycle; also called fertility awareness or natural family planning. 1. The basal body temperature (BBT) method uses daily temperature readings to identify the time of ovulation. 2. In the ovulation or Billings methods, women identify the relationships of changes in cervical mucus to fertile and infertile days. 3. The symptothermal method charts changes in temperature, cervical mucus, and other symptoms of ovulation (e.g., intermenstrual pain).

Pituitary gland

A small gland located at the base of the brain beneath the hypothalamus; serves as one of the chief regulators of body functions, including fertility. Most endocrine glands in the body are controlled by the pituitary. Also known as the hypophysis.

Post-placental insertion

1. Manual post-placental IUD insertion which occurs immediately following delivery of the placenta. 2. immediate postpartum insertion occurs during the first week after delivery.

Postpartum

After childbirth.

Potential reproductive years

Years between menarche and menopause.

Pregnancy

The interval from the completion of implantation of the blastocyst in the uterus until parturition.

Progesterone

A steroid hormone produced by the corpus luteum, adrenals, or placenta. It is responsible for changes in the uterine endometrium in the second half of the menstrual cycle which are preparatory for implantation of

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

the fertilized ovum, development of maternal placenta after implantation, and development of mammary glands.

Progestins

A large group of synthetic drugs that have a progesterone-like effect on the uterus.

Prostaglandin

Refers to a group of naturally occurring, chemically related long-chain fatty acids that have certain physiological effects (stimulate contraction of uterine and other smooth muscles, lower blood pressure, affect action of certain hormones). When prostaglandins are produced as the endometrial lining degenerates, they may cause mild to severe menstrual cramps, diarrhea, nausea, and vomiting. Oral contraceptives diminish the prostaglandins released by the endometrial lining, decreasing menstrual cramps in users.

Prostate

A pale, firm, partly muscular, partly glandular body that surrounds the base of the male urethra in man and other mammals and discharges its viscid opalescent secretion through ducts opening into the floor of the urethra.

Puberty

The age when sex organs become functionally operative and secondary sex characteristics develop. Puberty is defined as the state or quality of being first capable of bearing offspring or the period at which sexual maturity is reached. The dictionary says the age of puberty is commonly designated legally as 14 years for boys and 12 years for girls. For a girl, puberty means producing an ovum, and for a boy it is manufacturing spermatozoa. Secondary sexual characteristics in girls include breasts development, enlargement of the hips, and the development of axillary and pubic hair. In boys they include appearance of pubic, facial, and axillary hair; growth of the penis, testicles and scrotum; and deepening of the voice.

R

Reproductive intentions

Intentions to postpone or terminate childbearing.

S

Saturation mutagenesis

Selectively mutating all genes within a species by mutating one gene per individual of the species until all the genes are mutated. Then the function of the genes can be determined.

Semen

The thick, whitish fluid which normally contains sperm and seminal secretions and is ejected during ejaculation.

Seminal vesicles

Two glandular structures located behind the prostrate gland which secrete a component of semen.

Sexually transmitted diseases (STD)

Any disease that is communicated primarily or exclusively through intimate sexual contact. Sexually transmitted diseases have been estimated to cause from 20% to 40% of infertility in the U.S. STDs can adversely affect fertility by three primary mechanisms; pregnancy wastage, prenatal deaths, and damage to male or female reproductive capacity. Also called venereal disease or VD, sexually transmitted infections or STIs, or sexually transmitted reproductive tract infections or RTIs.

Side effect

An effect of a drug other than the one it was administered to evoke.

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

Spacing intentions

Preferred length of the next birth interval.

Sperm

Male reproductive cell.

Sperm antigens

Substances on or in the sperm that in certain circumstances elicit the production of antibodies.

Spermatogenesis

The formation of spermatozoa.

Spermicide

A chemical substance that kills sperm, marketed in the form of foam, cream, jellies, and suppositories used for contraception. The spermicides used in almost all currently marketed spermicides are surfactants, surface-active compounds that destroy sperm cell membranes.

Sponge

The light fibrous skeleton of certain aquatic animals used as an absorbent. Natural sea sponges have been used for centuries as contraceptives. In 1983 the U.S. Food and Drug Administration approved a vaginal contraceptive sponge, the Today sponge, a polyurethane sponge that contains 1 gram of the spermicide nonoxynol-9, which is available without a prescription.

Sterilization (Tubal ligation, Vasectomy)

A surgical procedure which leaves the male or female incapable of reproduction. Sterilization is the most commonly employed method of birth control in the world.

Steroidogenesis

The natural production of steroids. The usual progression of hormones is from progesterone and other progestins to androgens to estrogens.

T

Testosterone

Male sex hormone produced in the testes.

Transgenesis

Introduction of a gene.

U

Unintended pregnancy

One that was not wanted at the time conception occurred, irrespective of whether contraception was being used.

Unwanted conception

One that occurred when the woman did not want to have any more pregnancies at all.

Uterus

The hollow, pear-shaped, muscular, elastic reproductive organ where the fetus develops during pregnancy.

V

Vagina

The 3- to 5-inch long muscular tube leading from the external genitals of the female to the uterus. The external opening, called the introitus, may be diminished by a membrane called hymen. Sometimes called the birth canal, the vagina is the passageway through which babies are born and menstrual fluid flows. The vagina widens and lengthens during sexual arousal.

Validity

A principle of epidemiology used in connection with screening tests, which consists of sensitivity (ability to identify correctly those who have a given disease) and specificity (ability to identify correctly those who do not have a given disease).

Vas deferens

The tube through which sperm pass from the epidydimis to the ejaculatory duct and then into the urethra. It is this tube which is interrupted

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×

in the male sterilization procedure called vasectomy. Also called ductus deferens.

Vasectomy

A surgical procedure in which segments of the vas deferens are removed and the ends tied to prevent passage of sperm. Vasectomy should be regarded as permanent, although reversal is possible in some cases.

W

Withdrawal (coitus interruptus)

Removing the penis from the vagina just prior to ejaculation.

Women in fertile age (WIF)

Females of childbearing age, typically defined as between ages 15 and 44 or between ages 15 and 49.

Z

Zygote

The fertilized egg before it starts to divide.

Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
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Suggested Citation:"Glossary." Institute of Medicine. 1996. Contraceptive Research and Development: Looking to the Future. Washington, DC: The National Academies Press. doi: 10.17226/5156.
×
Page 504
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The "contraceptive revolution" of the 1960s and 1970s introduced totally new contraceptive options and launched an era of research and product development. Yet by the late 1980s, conditions had changed and improvements in contraceptive products, while very important in relation to improved oral contraceptives, IUDs, implants, and injectables, had become primarily incremental. Is it time for a second contraceptive revolution and how might it happen?

Contraceptive Research and Development explores the frontiers of science where the contraceptives of the future are likely to be found and lays out criteria for deciding where to make the next R&D investments.

The book comprehensively examines today's contraceptive needs, identifies "niches" in those needs that seem most readily translatable into market terms, and scrutinizes issues that shape the market: method side effects and contraceptive failure, the challenge of HIV/AIDS and other sexually transmitted diseases, and the implications of the "women's agenda."

Contraceptive Research and Development analyzes the response of the pharmaceutical industry to current dynamics in regulation, liability, public opinion, and the economics of the health sector and offers an integrated set of recommendations for public- and private-sector action to meet a whole new generation of demand.

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