Mother's Health Is Best for Baby

• Protecting and Ensuring the Mother's Health
• Transmission

Protecting and Ensuring the Mother's Health

Your own health and your own treatment are the most important things to consider to ensure a healthy baby.

This cannot be stressed enough.

Sometimes medical research can forget the fact that HIV-positive pregnant women are people who need care for their own HIV infection. This can sometimes be neglected or forgotten by mothers and healthcare workers when the baby's health is the main focus. You should not forget this, though: your health and care are very important.

Overall, your treatment should be largely the same as if you were not pregnant. Circumstances where this is not the case will be mentioned later on in this booklet.

Prevention of transmission and the health of your baby have a direct link to your own care. Prenatal counselling for HIV-positive woman should always include:

• advice and discussion about how to prevent mother to child transmission;
• information about treating the mother's own HIV now; and
• information about treating the mother's HIV in the future.

Your child is certainly going to want you to be well and healthy as he or she grows up. And you will want to be able to watch him or her go to school and become an adult

Principles of care

• The mother should be able to make her own choices about how to manage the pregnancy. She should be able to choose her own treatment during the pregnancy.
• Healthcare workers should provide information, education and counselling that is impartial, supportive and nonjudgemental.
• HIV should be intensively monitored during pregnancy. This is particularly important as the time of delivery approaches.
• Opportunistic infections should be treated appropriately. Anti-HIV drugs should be used to reduce viral load to undetectable levels.
• Mothers should be treated in the best way to protect them from developing resistance to HIV drugs.
• Mothers should be able to make informed choices regarding how and when their babies will be born.

Transmission

How and why does transmission happen?

Despite remarkable achievements in reducing mother-to-child transmission (MTCT), we do not fully understand how it happens.

What we do understand, though, is that there are many factors that affect transmission. Of these, the level of the mother's viral load is the most important. We will look at these factors in this section.

MTCT of HIV can happen before, during or after birth.

Scientists have found several possible reasons for infection. Besides the mother's viral load, her low CD4 count and whether she has AIDS illnesses make it more likely.

The exposure of the baby to a mother's infected blood or other body fluids during pregnancy and delivery, as well as breastfeeding are thought to be how transmission happens.

But most transmissions happen during delivery when the baby is being born.

More rarely, some transmissions happen during pregnancy before delivery. This is called in utero transmission.

Transmission during pregnancy (in utero)

This may happen if the placenta is damaged, making it possible for HIV-infected blood from the mother to transfer into the blood circulation of the foetus.

Chorioamnionitis, for example, has been associated with damage to the placenta and increased transmission risk of HIV.

This is thought to happen either via infected cells traveling across the placenta, or by progressive infection of different layers of the placenta until the virus reaches the foetoplacental circulation.

The reason we know that in utero transmission happens is that a proportion of HIV-positive babies tested when they are a few days old already have detectable virus in their blood. The rapid progression of HIV disease in some babies has also made scientists conclude that this happens.

Having a high viral load, AIDS and a low CD4 make in utero transmission more likely.

Having TB (tuberculosis) at the same time also makes it more likely and HIV makes in utero transmission of TB more likely.

Malaria also increases the risk of HIV transmission.

During labour and delivery (intrapartum transmission)

In utero is within the uterus or womb before the onset of labour. Intrapartum means occurring during delivery (labour or child birth). Placenta is a temporary organ that develops in pregnancy and joins the mother and foetus. The placenta acts as a filter. It transfers oxygen and nutrients from the mother to the foetus, and takes away carbon dioxide and waste products. The placenta is full of blood vessels. The placenta is expelled from the mother's body after the baby is born and it is no longer needed. It is sometimes called the afterbirth. Foetoplacental circulation is the blood supply in the foetus and placenta. Foetal membranes are the membranes surrounding the foetus. Maternal-foetal microtransfusions are when small amounts of infected blood from the mother leak from the placenta to the baby during labour (or other disruption of the placenta). Chorioamnionitis is inflammation of the chorion and the amnion, the membranes that surround the foetus. Chorioamnionitis is usually caused by a bacterial infection. Mucosal lining is the moist, inner lining of some organs and body cavities (such as the nose, mouth, vagina, lungs, and stomach). Glands in the mucosa make mucous, a thick, slippery fluid. A mucosal lining is also called a mucous membrane. Gastrointestinal tract is the tube that runs from the mouth to the anus and where we digest our food. The gastrointestinal tract begins with the mouth and then becomes the oesophagus (food pipe), stomach, duodenum, small intestine, large intestine (colon), rectum and, finally, the

Transmission during labour and delivery is thought to happen when the baby comes into contact with infected blood and genital secretions from the mother as it passes through the birth canal.

This could happen through ascending infection from the vagina or cervix to the foetal membranes and amniotic fluid, and through absorption in the digestive tract of the baby.

Alternatively, during contractions in labour, maternal-foetal microtransfusion may occur.

Scientists know that transmission occurs during delivery because:

• 50 per cent of HIV-positive babies test HIV-negative in the first few days of life.
• There is a rapid increase in the rate of detection of HIV in babies during the first week of life.
• The way that the virus and the immune system behave in some newborn babies is similar to that of adults when they first become infected.

It is also shown by the ways to prevent it happening. These include:

• Lowering the mother's viral load with ARVs; and
• Delivering the baby by Caesarean section before labour starts.

If it takes a long time to deliver after the membranes have ruptured (waters breaking) or if there is a long labour, risk of transmission in women not receiving ARV treatment or prophylaxis is increased.

A premature baby may be a higher risk of HIV transmission than a full term baby.

Breastfeeding

Doctors think that HIV in breastmilk gets through the mucosal lining of the gastrointestinal tract of infants. The gastrointestinal tract of a young baby is immature and more easily penetrated than that of adults

It is unclear whether damage to the intestinal tract of the baby, caused by the early introduction of other foods, particularly solid foods, could increase the risk of infection.

In the UK all HIV positive women are recommended to formula feed their babies to protect them from HIV. (See Feeding Your Baby: Risks and Options)

The most important thing to know about MTCT is not how it happens, but how we can prevent it from happening. We can do this with ARVs. Fortunately we know a lot more about that!