Pregnancy Awareness: Education on Immunization and Tests during Pregnancy | Interview with Pasteur Institut du Cambodge
Healthwise Digest (HD): What are the most common tests for pregnancy?
Institut Pasteur du Cambodge (IPC): Let’s divide these tests into two parts. First are before pregnancy, the pre- marriage stage and the second are during pregnancy. The common tests taken during pregnancy are HIV, Syphilis, Rubella, Toxoplasmosis, and blood grouping. Tests such as Hepatitis B, Hepatitis C, Mycoplasma and Chlamydiae are done after these were prescribed by physicians. For some couples, they come to take blood test when planning a pregnancy while some others only come after getting pregnant. When planning a pregnancy, we repeat all tests as well as blood grouping. Blood grouping is to avoid foeto-maternal incompatibility, when the father is Rh+positive and the mother Rh negative. We have to prevent this incompatibility and we now know how to prevent it, as sometimes this reaction could be fatal for the baby. As for thalassemia, we do a Complete Blood Count and Haemoglobin Electrophoresis. Furthermore, women who do not have any clinical history of rubella or chickenpox and are planning a pregnancy can undergo Control Serological Screening. The Commission on Specialized Safety of the French High Council for Public Health recalls any vaccination against varicella or rubella in a woman of childbearing age must be preceded by a negative pregnancy test and an effective contraception is recommended three months after each dose of vaccine.
HD: What are the specific tests for pregnancy in each semester?
IPC: All tests mentioned above, aside from the prescribed ones, are mandatory from the beginning of pregnancy. The toxoplasmosis, a disease that results from infection with the Toxoplasma gondii parasite, is primarily done to determine if there is a risk for such parasite infection during pregnancy. This parasite is transmitted through cats or consumption of raw meat. Toxoplasmosis is quite common in Cambodia but people here are not aware about this. Many doctors here are more concerned on Rubella and chicken pox. For toxoplasmosis, women who do not have any antibodies, should continue the test every month for the whole pregnancy and they should also repeat the test of rubella at least till 22nd week of pregnancy, if the screening is negative. If after this duration the mother is without rubella, they can stop taking this test. On the other hand, we also do glycosuria and albuminuria. These tests are mandatorily done every month to check if the mother is at risk of acquiring diabetes and pre-eclampsia. Sometimes, they need to check with their OB-Gyne if they have gestational diabetes especially if they have high body mass index (BMI) and other criteria which we noted high risk. We must also make monthly regular monitoring of hemoglobin to prevent anemia in pregnancy and initiate treatment with folic acid and iron.
In the 4th month, we screen for Trisomy, which is among the highest number of conditions in pregnancy. People seem to be unaware of this. As laboratory specialists, we can’t make any medical decision and it is out of scope of what to do. After finding out that there’s a trisomy case, we have to send them for a specialist doctor for further advice. For this screening test, which is non-invasive, we just take the blood sample from the mother. Since this is a genetic test, informed consent of the mother is mandatory. If it turned out positive then we need to do another test that is invasive for confirmation.
When the mother is Rh negative and the father Rh-positive, there is no risk during the first pregnancy. The risk appears after childbirth, during the passage of the child’s red blood cells in the bloodstream of the mother. In a future pregnancy, she will then produce antibodies against the red blood cells of the child. To avoid this, during childbirth, anti-D immunoglobulin injection is given immediately after delivery to the mother with Rh negative if the father has Rh positive to prevent incompatibility feto-maternal incompatibility in a further pregnancy.to the mother. In a new pregnancy, irregular antibodies screening and especially the blood group of the baby (molecular test) must to be done. For, if the baby is rhesus negative, there is no risk.
Test for Hepatitis B antigen (HBs Ag) is useful for newborn management. In case the test is positive for Hepatitis B, we must give the baby immunoglobulin (Ig) injection in the first 24 hours after labor or as soon as possible. Our Pasteur institute can provide this type of Ig. We divide the phases of infection Hepatitis B into 3 phases. According to pathophysiology, there are prenatal, perinatal and post natal. However, if the baby gets infected during prenatal, the injected Ig and hepatitis B zero will not help them. Luckily, the incident of pre-natal transmission by placenta is low. The purpose of giving Ig and hepatitis B vaccine at birth is to prevent the peri-natal and post-natal transmission from the mother towards her baby.
For the third trimester, we conduct a vaginal swab for Streptococcus group B.
HD: What are the vaccines available during pregnancy?
IPC: It is important to remember that consideration is always a safe choice. It’s the things needed to do before couples decide to have baby. First they should remember whether they have taken the vaccines before or not, and if they already had, a booster for those for some vaccines is recommended. We’re highly concerned about the viral infections we mentioned, which can cause congenital malformation. These also include Hepatitis B vaccine. Those diseases are preventable and women should check if they have antibodies against them. In case they don’t have yet, they can do Measles Mump Rubella (MMR) vaccine and Varicella vaccine. Since these are live virus vaccines, they need to get these at distance before they get pregnant.
Hepatitis B vaccine can be given during pregnancy.
During pregnancy, the following vaccines should be given according to the recommendations of the World Health Organization (WHO) and the US Center for Disease Control (US-CDC):
Tetanus Vaccine: The main purpose is to prevent neonatal tetanus in newborn baby at birth and in the mother during labor. It is recommended that pregnant women get at least 2 doses of tetanus vaccine during her pregnancy. Usually pregnant women are a bit late to start medical checkup, thus late to get the first dose of tetanus vaccine. They normally take the 1st dose during the second trimester and onwards.
Hepatitis B Vaccine: This vaccine is safe to take during pregnancy. If the expectant mother doesn’t have any antibody, she should get this vaccine.
Influenza Vaccine: The immune system during pregnancy is weak. Pregnant women are recommend to receive influenza vaccine during third trimester onwards. We have two reasons to take this at the third trimester: one is to prevent the mother from acquiring flu and second is to obtain passive immunity transferred to the fetus so that the newborn are protected from the disease before they can even get the vaccine after birth (for babies, this vaccine can be given only from age sixth months).
HD: Is there any available newborn screening test here?
IPC: Globally, it’s part of their policy to provide newborn screening, but locally we can’t afford it and there’s no possibility of doing all the tests yet. However, there are also some test we do routinely like G6PD (glucose-6-phosphate dehydrogenase) and thyroid unction test for instance. Sometime we also screen for haemopathy, depending on the case.
HD: Can you cite the services offered for pregnant women and babies here at IPC?
IPC: At IPC, we have two important services for pregnant women: vaccination and laboratory analyses. For vaccination, we have Measles-Mumps-Rubella vaccine (3 in 1), Chicken pox, Hepatitis B and Flu vaccines. Likewise, parents should consider about vaccination plan for their babies. IPC has vaccines for babies from birth till 18 years of age corresponding to routine vaccines (against 10 diseases namely tuberculosis, hepatitis B, tetanus, diphtheria, pertussis, polio, haemophilus influenzae b or Hib, measles, rubella, pneumococcus) according to the National Immunization Program of the Ministry of Health. In addition, IPC also has vaccines against rotavirus, seasonal flu, mumps, varicella, hepatitis A, typhoid fever, Japanese encephalitis, cervical cancer, meningitis and yellow fever.
HD: What important advice you can share to women if they are planning to get pregnant or if they are already pregnant?
IPC: They should have proper plan for safe pregnancy. These include regular health checkup, biological testing and immunization. The earlier a health problem is identified, the easier the problem can be managed. Don’t let vaccine preventable diseases affect you, your pregnancy and your baby.