Malaria in pregnancy is a obstetric, social and medical problem requiring multidisciplinary and multidimensional solution. Pregnant women constitute the main adult risk group for malaria and 80% of deaths due to malaria in Africa occur in pregnant women and children below 5 years. In Africa, perinatal mortality due to malaria is at about 1500/day. In areas where malaria is endemic, 20-40% of all babies born may have a low birth weight. Malaria in pregnancy is a Priority Area in Roll Back Malaria strategy.
Malaria and pregnancy are mutually aggravating conditions. The physiological changes of pregnancy and the pathological changes due to malaria have a synergistic effect on the course of each other, thus making the life difficult for the mother, the child and the treating physician. P. falciparum malaria can run a turbulent and dramatic course in pregnant women. The non- immune, primi gravidae are usually the most affected. In pregnant women the morbidity due to malaria includes anemia, fever illness, hypoglycemia, cerebral malaria, pulmonary edema, puerperal sepsis and mortality can occur from severe malaria and haemorrhage. The problems in the new born include low birth weight, prematurity, IUGR, malaria illness and mortality.
Complications of malaria in pregnancy:
Anemia: Malaria can cause or aggravate anemia. It could be due to the following causes:
Hemolysis of parasitised red blood cells.
Increased demands of pregnancy.
Profound hemolysis can aggravate folate deficiency.
Anemia due to malaria is more common and severe between 16-29 weeks. It can develop suddenly, in case of severe malaria with high grades of parasitemia. Pre existing iron and folate deficiency can exacerbate the anemia of malaria and vice versa.
Anemia increases perinatal mortality and maternal morbidity and mortality. It also increases the risk of pulmonary oedema. Risk of post-partum haemorrhage is also higher.
Significant anemia (Hemoglobin <7-8 g%) may have to be treated with blood transfusion. In view of the increased fluid volume in pregnancy, it is better to transfuse packed cells than whole blood. Rapid transfusion, particularly whole blood, may cause pulmonary oedema.
Immuno suppression:
Immunosuppression in pregnancy poses special problems. It makes malaria more common and more severe. And to add to the woes, malaria itself suppresses immune response.
Hormonal changes of pregnancy, reduced synthesis of immunoglobulins, reduced function of reticulo endothelial system are the causes for immunosuppression in pregnancy. This results in loss of acquired immunity to malaria, making the pregnant more prone for malaria. Malaria is more severe with higher parasitemia. Patient may have more frequent paroxysms of fever and frequent relapses.
Secondary infections (UTI and pneumonias) and algid malaria (septicaemic shock) are more common in pregnancy due to immunosuppression.
Risks for the foetus:
Malaria in pregnancy is detrimental to the foetus. High grades of fever, placental insufficiency, hypoglycemia, anemia and other complications can all adversely affect the foetus. Both P. vivax and P. falciparum malaria can pose problems for the foetus, with the latter being more serious. The prenatal and neonatal mortality may vary from 15 to 70%. In one study, mortality due to P. vivax malaria during pregnancy was 15.7% while that due to P. falciparum was 33%. Spontaneous abortion, pre mature birth, still birth, placental insufficiency and IUGR (temporary / chronic), low birth weight, fetal distress are the different problems observed in the growing foetus. Transplacental spread of the infection to the foetus can result in congenital malaria.
P. vivax malaria in pregnancy:
There are very few documented studies on P. vivax malaria in pregnancy. It appears to be more common in primigravidae than multigravidae. Parasite densities are similar in pregnant and non-pregnant states. It may be associated with mild anaemia and increased risk of low birth weight and not associated with abortion, stillbirth or a reduction of the duration of pregnancy. Benefit of chemoprophylaxis has not been established.
Management of Malaria in Pregnancy:
Management of malaria in pregnancy involves the following three aspects and equal importance should be attached to all the three.
Treatment of malaria
Management of complications
Management of labour
Treatment of malaria:
Treatment of malaria in pregnancy should be energetic, anticipatory and careful.
Energetic:
Don't waste any time.
It is better to admit all cases of P. falciparum malaria.
Assess severity- General condition, pallor, jaundice, BP, temperature, hemoglobin, Parasite count, SGPT, S. bilirubin, S. creatinine, Blood sugar.
Anticipatory: Malaria in pregnancy can cause sudden and dramatic complications. Therefore, one should always be looking for any complications by regular monitoring.
Monitor maternal and fetal vital parameters 2 hourly.
RBS 4-6 hourly; hemoglobin and parasite count 12 hourly; S. creatinine; S. bilirubin and Intake / Output chart daily.
Careful: The physiologic changes of pregnancy pose special problems in management of malaria. In addition, certain drugs are contra indicated in pregnancy or may cause more severe adverse effects. All these factors should be taken into consideration while treating these patients.
Choose drugs according to severity of the disease/ sensitivity pattern in the locality.
Avoid drugs that are contra indicated
Avoid over / under dosing of drugs
Avoid fluid overload / dehydration
Maintain adequate intake of calories.
Anti malarials in pregnancy:
All trimesters: Chloroquine; Quinine; Artesunate / Artemether / Arteether
2nd trimester: Mefloquine; Pyrimethamine / sulfadoxine
3rd trimester: Mefloquine; ?Pyrimethamine / sulfadoxine
Contra indicated: Primaquine; Tetracycline; Doxycycline; Halofantrine
Management of complications:
Management of labour:
Anemia, hypoglycemia, pulmonary oedema, and secondary infections due to malaria in full term pregnancy lead to problems for both the mother and the foetus. Severe falciparum malaria in full term pregnancy carries a very high mortality. Maternal and fetal distress may go unrecognised in these patients. Therefore, careful monitoring of maternal and foetal parameters is extremely important and pregnant women with severe malaria are better managed in an intensive care unit.
Falciparum malaria induces uterine contractions, resulting in premature labour. The frequency and intensity of contractions appear to be related to the height of the fever. Fetal distress is common and often unrecognised. Therefore only monitoring of uterine contractions and fetal heart rate may reveal asymptomatic labour and foetal tachycardia, bradycardia or late deceleration in relation to uterine contractions, indicating fetal distress. All efforts should be made to rapidly bring the temperature under control, by cold sponging, anti pyretics like paracetamol etc.
Treatment of vivax malaria in pregnancy:
In pregnancy, use of primaquine is contraindicated. Therefore to prevent the relapse of vivax malaria from reactivation of hypnozoites in the liver, suppressive chemoprophylaxis with chloroquine is recommended. Tablet Chloroquine 500 mg weekly should be administered to all such patients until delivery. At that point, a complete treatment with full therapeutic dose of chloroquine and primaquine should be administered.
Vaccine against malaria in pregnancy: Although a general malaria vaccine appears to be a distant possibility, there is much hope for a vaccine against placental malaria. The administration of excessive soluble CSA to pregnant women has proven to drastically reduce parasite adhesion; however, in excess levels, this soluble protein is severely nephrotoxic. Studies have demonstrated that the administration of chondroitinase AC can effectively reduce parasite adhesion by 95%. This preliminary data is being further tested in combination with therapeutic use of monoclonal antibodies to CSA
