Confirmatory and Screening Tests
Screening During Pregnancy
Confirmatory Urine Test:
When a woman becomes pregnant, her body produces a hormone called hCG (human Chorionic Gonadotropin). Shortly after fertilization, the placenta starts secreting this and this hormone appears in the urine.
In general, the hCG level will double every 2-3 days in early pregnancy.
In a normal pregnancy, hCG can be detected in serum as early as 7 days following conception. Usually a urine test is advised and is enough to confirm pregnancy.
In some cases an ultrasound and /or serum hCG (a blood test) may be advised. After 12 weeks foetal heart tones can be heard on a Doppler.
Home Pregnancy Kits
The dipstick colour change urine tests are fairly accurate in normal pregnancies. Several brands of these are available across the counter.
Screening During Pregnancy
The Gynaecologist will examine the pregnant woman thoroughly.
A physical exam may include:
- A general examination.
- Inspection of external genitalia.
- Internal examination of vagina and cervix.
- Assessment of the size and shape of the bony pelvis.
The following parameters may be measured:
Blood Typing and Grouping:
Blood type could be A, B, AB, or O. It can be Rh positive or Rh negative, depending on the presence of a protein factor “Rh”. Problems can arise when the foetus’s blood has the Rh factor and the mother's does not. The mother's body may react as if it were allergic to the foetus. It will make antibodies that attack the foetus' blood. This can cause anaemia (low iron levels). It will require special care during pregnancy.
Blood tests to screen for:
Haemoglobin levels and Packed Cell Volumes are measured to check for Anaemia.
The blood test for syphilis is called a VDRL (Venereal Disease Research Laboratory). Syphilis is a Sexually Transmitted Disease. Syphilis can be treated. If the pregnant woman has syphilis and is not treated, she could pass it to the baby.
Blood will be checked for signs of past German measles (rubella). If the mother has had this condition before, she is not likely to get it again. If she hasn't had it, while she is pregnant she has to avoid anyone who has the disease.
Hepatitis B virus
Hepatitis B infects the liver. If a pregnant woman has this infection, she can pass it on to the baby. A drug called hepatitis B immune globulin may be given to help treat the illness. The baby will be given the same medication and a vaccine against the disease after birth.
In case there is a strong family history of Diabetes Fasting Sugar and Post Prandial blood sugar tests are performed.
Human Immunodeficiency Virus (HIV)
HIV is the virus that causes AIDS (acquired immunodeficiency syndrome). Pregnant women are tested even if they do not have special risk factors. If the woman has HIV, there is a chance that she can pass it on to the baby. She can be given medication during pregnancy to reduce this risk.
Routine Urine Test
Urine will be tested at each prenatal visit. This test checks the levels of sugar and protein. Often, sugar in the urine is normal in pregnancy. High levels of sugar could be a sign of diabetes.
Urine tests can detect urinary tract, bladder or kidney infection, kidney disease, or high blood pressure that can occur later in pregnancy.
In cases where there may be complications certain other tests are prescribed.