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Can Toxoplasmosis infection in pregnancy lead to miscarriage or stillbirth?
Yes. Again, infection in the earlier phase of pregnancy increases a risk of such an outcome. It is less likely, the more advanced the pregnancy is.
Since not every fetus is affected by the infection, what is the advice to an expectant mother confirmed to have the Toxoplasmosis infection?
The risk to the fetus will be assessed, normally using ultrasound. If features suggestive of congenital toxoplasmosis infection are there, advice may be given to perform a fetal blood sampling, which will confirm or exclude the diagnosis in most (not all) cases.
Since the extent of damage and resultant disability is difficult to quantify before delivery, it is normally up to the parents to decide whether to proceed with the pregnancy or not. Unfortunately, termination is never an easy option after the tests, because they can only be carried out rather late in pregnancy, certainly not before twenty weeks of gestation.
Is there any treatment if the fetus is infected and parents want to continue with the pregnancy?
Yes. There are a few treatment options that may be used by any mother with primary toxoplasmosis infection, even in the absence of documented fetal infection. This is because, in theory, the treatment may reduce the risk of fetal infection or at least moderate it. The doctor should fully explain the potential side-effects of the chosen drug and how long it needs to be used to confer the required benefit.
One of the options, spiramycin, is claimed to reduce the risk of fetal infection by half. The other, which is a combination of pyrimethamine and a sulphonamide, is similarly - if not more - protective.
Does secondary toxoplasmosis infection to the mother pose a similar amount of risk?
No. Secondary infection is probably an inappropriate term. Some people with toxoplasmosis have unusual manifestations, such as eye lesions. In such cases, the eye lesions may flare up months or years after the primary infection. There is no evidence that specific action is required, as far as the pregnancy is concerned.
For somebody with primary toxoplasmosis infection, are there any special measures regarding delivery?
Not normally. Of course, the method of delivery will depend on all the usual obstetric variables. If the fetus is affected and one of the features is an abnormally large head (hydrocephalus), a caesarean section may be opted for, as long as the baby is viable.
Paediatricians will be on hand at delivery to give the required immediate treatment, if any.
Will Toxoplasmosis infection in one pregnancy have any bearing on further pregnancies?
No. Babies in subsequent pregnancies will not be affected.
Surely all this risk calls for universal screening for toxoplasmosis in earlier pregnancy?
As mentioned before, different population groups have varying degrees of risk, depending on life-style. Moreover, there is evidence that 25 to 50 per cent will have had the infection in the past and are therefore not at risk.
Some countries, such as France, offer the screen test to all mothers, because the prevalence of the disease there is relatively high. Most other countries do not and instead target those expectant mothers at risk. These will include those keeping cats and those whose occupations involve frequent handling of raw meat or cat litter.
What is the general advice against toxoplasmosis infection?
Avoid eating raw meat and eggs
Ensure meat is properly cooked, or at least frozen to minus 20ºC prior to cooking, if it is to be done rare.
Use milk which has been pasteurised.
Avoid cat litter or, if this is not possible, ensure protective gloves are used each time.
Use gloves when gardening.
Wash vegetables thoroughly before consumption.
Last update: March 2, 2013