Encyclopedia of Health and Medicine

The Reproductive System 237
strual cycles. The ovaries contain a finite number
of ova, present at birth. From the onset of MEN-
STRUATION to midlife, each monthly cycle causes a
half dozen to a dozen ovarian follicles to ripen.
Usually only one ovum (egg) reaches full maturity
and leaves the ovary; the others atrophy (shrink)
and the ovary reabsorbs them. By midlife the
ovaries have made it pretty much through their
supply of ova, far fewer follicles activate with each
MENSTRUAL CYCLE, and ovarian function begins to
shut down. Over a period of five to eight years,
menstrual cycles become irregular and eventually
infrequent until they stop altogether.
Health and Disorders of the Reproductive System
The health of the reproductive system, male or
female, experiences internal and external influences.
Internally the reproductive system relies
significantly on an intricate hormonal balance as
hormones direct nearly all sexual and reproductive
functions. Disorders are often endocrine in
origin. The organs of reproduction are particularly
vulnerable to cancers that thrive on hormones,
such as BREAST CANCER, OVARIAN CANCER, ENDOME-
TRIAL CANCER, PROSTATE CANCER, and TESTICULAR CAN-
CER. Externally the reproductive system is
vulnerable to injury and illness, to great extent
through sexual activity. SEXUALLY TRANSMITTED DIS-
EASES (STDS) can cause serious and sometimes lifethreatening
health conditions. STDs are a leading
cause of INFERTILITY in women and can cause illness
in newborns who are exposed during birth. Other
factors that can affect reproductive health include
exposures to chemicals such as pesticides or to
radiation, which can damage the DNA of sperm or
ova.
External factors are particularly important during
pregnancy, when certain exposures at vulnerable
points of fetal development can cause
permanent injury. INFECTION with common viruses
such as RUBELLA (German MEASLES) or measles can
cause devastating BIRTH DEFECTS, as can taking certain
drugs and medications. Nearly any substance
the woman takes into her body may cross the PLA-
CENTA to enter the fetus’s BLOOD circulation. FETAL
ALCOHOL SYNDROME, a constellation of physical birth
defects and developmental abnormalities that
occurs as a result of fetal exposure to ALCOHOL, is
entirely preventable.
HEALTH CONDITIONS OF THE REPRODUCTIVE SYSTEM
ADENOMYOSIS
BALANITIS
BENIGN PROSTATIC HYPERPLASIA
(BPH)
CERVICAL CANCER
CHORDEE
CRYPTORCHIDISM
ECLAMPSIA
ENDOMETRIAL CANCER
ENDOMETRIOSIS
ERECTILE DYSFUNCTION
FIBROCYSTIC BREAST DISEASE
HEMATOSPERMIA
HYPOGONADISM
INTRADUCTAL PAPILLOMA
MASTALGIA
NABOTHIAN CYST
ORCHITIS
OVARIAN CYST
PARAPHIMOSIS
PHIMOSIS
PREECLAMPSIA
PREMATURE OVARIAN FAILURE
PRIAPISM
PROSTATE CANCER
SEXUAL DYSFUNCTION
SPERMATOCELE
TESTICULAR CANCER
TURNER’S SYNDROME
UTERINE PROLAPSE
VARICOCELE
AMENORRHEA
BARTHOLIN CYST
BREAST CANCER
CANCER OF THE PENIS
CERVICAL INTRAEPITHELIAL
NEOPLASIA (CIN)
DYSMENORRHEA
ECTOPIC PREGNANCY
ENDOMETRIAL HYPERPLASIA
EPIDIDYMITIS
fibroadenoma
GYNECOMASTIA
HYDROCELE
INFERTILITY
KLINEFELTER’S SYNDROME
MASTITIS
NEONATAL JAUNDICE
OVARIAN CANCER
PAGET’S DISEASE OF THE BREAST
PEYRONIE’S DISEASE
POLYCYSTIC OVARY SYNDROME
(PCOS)
PREMENSTRUAL SYNDROME
(PMS)
PROSTATITIS
SEXUALLY TRANSMITTED DISEASES
(STDS)
TESTICULAR TORSION
UTERINE FIBROIDS
VAGINITIS
VULVODYNIA
Traditions in Medical History
The high rate of maternal deaths from “childbirth
FEVER” (puerperal fever) at the dawn of the era of
antisepsis motivated Hungarian obstetrician Ignaz
Philipp Semmelweis (1818–1861) to change his
habits. In so doing, he transformed the practice of
obstetrics and saved countless lives. By the middle
of the 19th century scientists knew of the existence
of microbes and their role in causing disease,
though their mechanisms of infection remained a
mystery. An emerging recognition was of the danger
of infection for pathologists who performed
autopsies. The slight wound from a slip of the
scalpel was all too often fatal, causing systemic
infection known as pathologist’s pyemia. Semmelweis
was the first to connect the two apparently