Diagnosis and differential diagnosis of Pregnancy

It is advantageous to diagnose pregnancy as promptly as possible when a sexually active woman misses a menstrual period or has symptomps suggestive of pregnancy. in the event of a desired pregnancy,prenatal care can begin early, and potentially harmful medications and activities such as drug and alcohol use, smoking, and occupational chemical exposure can be halted. int eh event of an unwanted pregnancy, countseling about adoption or termination of the pregnancy can be provide at an early stage.

Pregnancy test
all urine or bloode pregnancy test rely on the detection of hCG produced by the placenta. hCG levels increase shortly after implantation, double approximately every 48 hours, reach a peak at 50-75 days, and fall to lower levels in the second and third trimester. Laboratory and home pregnancy test now use monoclonal antibodies specific for hCG. these tests are performed on urine or serum and are accurate at the time of missed period or shorty after it.
compared with intrauterine pregnancies, ectopic pregnancies may show lower level of hCG that level off or fall in serial determinations. quantitative assays of hCG repeated at 48 to 72 hours intervals are used in the diagnosis of ectopic pregnancy, threatened abortion, and missed abortion. comparison of hCG levels between laboratories may be misleading in a given patient because different international standards may  produce result that vary by as as much as twofold

Manifestations of Pregnancy
the following symptoms and signs are usually due to pregnancy, but none are diagnostic. a record of the time and frequency of coitus  is helpful for diagnosing and dating pregnancy.

A. Symptomps
Ammenorrhea nausea and vomiting, breast tenderness and tingling, urinary frequency and urgency, "quickening" ( noted about the 18th week), weigh gain
B. Sign
Breast changes (enlargement, vascular engorgement, colostrum), abdominal enlargement, cyanosis of vagina and cervical portio(7th week), softening of the cervix (about 7th week), softening of the cervicouterine junction (8th week),generalized enlargement and diffuse softening of the corpus (after 8th week)