Blood Tests and Investigations

Asymptomatic bacteriuria is a bladder infection that has no symptoms. Identifying and treating it can reduce the risk of developing a kidney infection. It can be detected by testing a urine sample (Mid stream urine).

Anaemia is caused by too little haemoglobin (Hb) in the red blood cells. The Hb is usually tested as part of the 'full blood count'. Hb carries oxygen and nutrients around the body and to the baby. Anaemia can make you feel very tired. If you are anaemic, you will be offered iron supplements and advice on diet . More information @Anemia in Pregnancy and Iron in your diet.

Blood group & antibodies This test tells us your blood group; whether your blood is Rhesus Positive (Rh +ve) or Negative (Rh -ve); and whether you have any antibodies (foreign blood proteins). If you are Rh-ve, you will be offered blood tests to check for antibodies. If your baby has inherited the Rh+ve gene from the father, antibodies to the baby's blood cells can develop in your blood. To prevent this, you will be advised to have 'anti-D' injections whenever there is a chance of blood cells from the baby spilling into your blood stream (e.g. due to miscarriage, amniocentesis or CVS, vaginal bleeding, a blow to the abdomen, and after the birth of the baby). It is recommended that Anti-D is given routinely to all Rh -ve mothers at 28 and 34 weeks of pregnancy.Until recently a maternal blood test (plasma DNA) can detect fatal Rh (+ve or -ve)in pregnancy and thereby identify which Rh-ve mother will need 'anti-D' injection. But, this test is expensive. It is available in Hong Kong.

Rubella (German measles) Rubella infection early in pregnancy can damage your baby. A test is offered to check your immunity (ability to fight infection). Most women are protected by routine rubella vaccinations given in childhood, but if you are not immune, you will be advised to be immunised after the birth. Inform your doctor if you develop a rash.

Hepatitis B is a virus which infects the liver. If you are a carrier of the virus or have become infected during pregnancy, you will be advised to have your baby immunised at birth to avoid infection.

Syphilis is a sexually transmitted disease and can seriously damage your baby if left untreated. If detected, treatment can be offered with antibiotics to control the infection and to help protect your baby.

HIV (Human Immunodeficiency Virus) affects the body's ability to fight infection. This test is important because any woman can be at risk. It can be passed on to your baby during pregnancy, at birth or through breastfeeding. Treatment given in pregnancy can greatly reduce the risk of infection being passed from mother to child. A negative test does not affect past or future life assurance claims.

Sickle cell and Thalassaemia are blood disorders that can be passed from parent to child. You will be offered a blood test if you are living in an area with high occurrence of the disorder, or if there is an increased chance of you being a carrier without knowing. This is the case if you or your family come from Africa, the Caribbean, India, Pakistan, Bangladesh, South East Asia, China, the Middle East, or Mediterranean countries (e.g. Greece, Italy, Turkey, Cyprus). The results may require the baby's father to be tested.

Additional tests may be offered as necessary, for example to check for infections which can cause damage to the developing baby, but rarely cause problems for the mother. Inform your doctor if you develop any rashes or if you think you have been in contact with any of the following:

• Chicken pox can cause problems to the developing baby if caught before 20 weeks of pregnancy. It can also be passed to the newborn baby if caught within 10 days prior to the birth.
• Cytomegalovirus (CMV) prevention involves careful hygiene especially thorough washing of hands.
• Parvovirus (Slapped cheek syndrome) often causes a red rash on the face and is mostly seen in children.
• Toxoplasmosis is caused by an organism that is found in cat faeces, so always wear gloves when gardening or changing cat litter. Also make sure that all food is washed and thoroughly cooked before it is eaten.
• Chlamydia is a sexually transmitted infection which can result in pelvic inflammatory disease and infertility. If you are under 25, you may be offered a simple test, either a vaginal swab or urine test. If positive, antibiotics will be offered to you and your partner.