premature ventricular contraction Contraction of the lower chambers of the heart, the ventricles, that occurs earlier than usual because of abnormal electrical activity of the ventricles. Abbreviated PVC. The premature contraction is followed by a pause as the heart’s electrical system resets itself; the contraction following the pause is usually more forceful than normal. These…
premature ejaculation Ejecting semen from the penis, usually accompanied by orgasm, occurring sooner than a man wants during sexual activity. Premature ejaculation is characterized by a lack of voluntary control over ejaculation that interferes with optimal sexual or psychological well-being in either partner.
premature contraction of the heart A single heartbeat that occurs earlier than normal. This phenomenon can be within normal limits, or it may represent a medically significant arrhythmia.
premature birth Birth before 37 weeks of gestation have passed. Premature birth carries increased risks the farther it occurs from the 37-week goal. Many procedures are available to prevent premature birth, from bed rest to medications. If premature birth is medically necessary or inevitable, however, it may be accomplished via C-section to limit stress on…
premature baby A baby who is born before 37 weeks of gestation have passed since the mother’s last menstrual period. A premature baby who is born very close to its due date may suffer few, if any, consequences. The earlier in development that birth takes place, the greater the likelihood that life-support systems will be…
premature aging disorder A condition that causes a person to appear far older than their actual age. See progeria; Werner syndrome.
premalignant Pertaining to tissue that is not yet malignant but is poised to become malignant. Appropriate clinical and laboratory studies are designed to detect premalignant tissue while it is still in a premalignant stage. A battery of techniques are available to remove or kill the tissue, thereby preventing the development of cancer. The proper treatment…
preleukemia See myelodysplastic syndrome.
prehypertension A precursor state to high blood pressure (hypertension) in which the systolic pressure is between 120 and 139 mm Hg or the diastolic pressure is between 80 and 89 mm Hg. Lifestyle changes are recommended for anyone with prehypertension. See also high blood pressure.
pregnancy planning Planning that addresses issues that may affect a woman’s ability to carry a child to term, such as nutrition, vitamins, body weight, exercise, potentially harmful medications and illnesses, immunizations, and genetic counseling. See also birth control; family planning.
pregnancy, tubal An ectopic pregnancy that takes place in a fallopian tube. Tubal pregnancies are due to the inability of the fertilized egg to make its way through the fallopian tube into the uterus. Tubal pregnancies account for 95 percent of all ectopic pregnancies. See also ectopic pregnancy.
pregnancy, pernicious vomiting of See hyperemesis gravidarum.