Malaria in Pregnancy

Malaria is a major threat to the life of a mother and her unborn child. The impact of the disease will depend on the strength of the mother‚ her immune system and the severity of the Malaria.

However, the fact remains that malaria during pregnancy reduces birth weight, and low birth weight is a major cause of infant mortality.

In the mother, malaria can have complications that include anaemia, fever, hypoglycemia, bleeding, post-natal infections, pulmonary oedema, cerebral malaria and death.

For the unborn child, an infection of Malaria can result in abortion, stillbirth, congenital infection or anaemia. Maternal anaemia and malaria infections in the second trimester reduce weight gain in the unborn child and can cause the fetus to grow more slowly, resulting in low birth weight and increasing the chances of infant mortality.

It has also been shown that if malaria is present in the placenta, maternal antibodies are not efficiently exchanged with the growing child, and thus, the child’s immunity is weakened.

Malaria is an insidious killer that is laying in wait for pregnant women and the children they carry.

When the mosquito bites its victim, it injects the parasites that cause Malaria into the bloodstream. These parasites initially travel to the liver and penetrate the liver cells where they are incubated for a time. After incubation, they explode into the bloodstream and invade red blood cells, where they multiply.

The red blood cells become filled with the new parasites and burst to release them to attack other red blood cells. At the same time, they also release poisons produced from the destruction of red blood cells, which causes fever. At this time, the symptoms of Malaria are first experienced as the body tries to grapple with the presence of the parasites in the blood.

After 36 to 72 hours (depending on the type of Malaria), the red blood cell is destroyed, and parasites in more significant numbers re-enter the bloodstream and attack more red blood cells. The destruction of large numbers of red blood cells is a significant cause of anaemia.

Once falciparum parasites enter the red blood cell, they cause the outside of the cell to become sticky, and the cell becomes less flexible. This causes the red blood cells to adhere to the lining of the capillaries in major organs such as the brain, liver and in the pregnant mother, the placenta.

With placental malaria, large numbers of red blood cells containing parasites lodge in the microcirculation of the placenta, which is rich in capillaries. Because of its relative isolation from the rest of the circulatory system, it is an ideal place for malaria parasites to multiply. Thus large numbers of new parasites are produced in the placenta. These are eventually released and attack more red blood cells, putting the mother and child at significant risk.

Blocking the capillaries in the placenta congests the microcirculation, resulting in hypoxia and blockage of nutrients to the unborn child. This can cause abortion, stillbirth, early labour, reduction of weight gain in the child, or slow the development of the growing fetus. The child can also be infected with malaria.

The people who are most at risk from malaria are women who are experiencing their first pregnancies and who are living in areas where stable malaria infections already exist.

Research has shown that limited immunity to malaria can develop if the mother has had the same strain of malaria more than once and the body has been able to develop limited resistance to the infection. Immunity to malaria can be short-lived and, in stable transmission areas, may only last a few months. However, whilst there are 5 types of malaria, there are hundreds of strains.

Researchers believe that limited immunity has a better chance of developing where only a single strain of malaria lives within the local area. Should different strains of malaria be introduced through the presence of carriers from other regions, then the limited immunity will not be of benefit to the victim. Even though a patient may have limited immunity and the impact of the infection is less severe, it does not decrease the danger to the fetus as the parasites are still present in the placenta.

A second issue with regard to limited immunity in pregnancy is that the limited immunity in a pregnant woman is less than in other victims of the disease. This is due to the suppression of the immune system in a woman’s body during pregnancy.

Placental malaria complicates the way that the disease is treated. If an infected pregnant mother is treated for malaria, sometimes tests will show that the antimalarial medications administered have successfully treated the disease. However, this may not be the case. Case studies show that the malaria parasites sequestered (hidden) in the placenta may be unaffected by antimalarial medication and that, in actual fact, despite blood tests showing the peripheral circulation to be parasite-free, the parasites have freely multiplied in the placenta to alarming levels, leaving both mother and child at serious risk.

The presence of the parasites in the placenta leads to patient re-infection. Therefore, the treated mother will need to be re-tested for malaria regularly after the initial treatment has ceased. In pregnant women, treatment may also need to be extended. When possible, pregnant women in malaria areas should be treated with intermittent preventative treatment (IPT) medications regardless of malaria infection status.

Pregnancy also limits the antimalarials that can be used to treat the disease, as some of the chemicals used are dangerous to the mothers’ health and to the viability of the fetus.