Also referred to as ‘amnio’, is a simple procedure to obtain a small quantity  of amniotic fluid (about 20mL) by inserting a special needle through the mother’s tummy and into the uterus. The needle will always be under ultrasound guidance so that it does not harm the fetus. The reasons for performing an amniocentesis test are essentially the same as that for doing a chorionic villus sampling. The amnio test is done after 16 weeks. The safety and complications of amnio test are also similar to CVS in experienced hands. Choosing between the two tests is a matter of preference by the physician: CVS has the advantage of early testing while amnio has the advantage of being widely available due to its technical simplicity.

Testing the fetal blood directly is required in certain conditions. Commonly, when there is  accumulation of fluid inside the fetus (hydrops), fetal blood sampling  is required to find out the cause. In other situations, the reasons for testing is essentially the same as that of chorionic villus sampling or amniocentesis. Generally, when the testing has to be done beyond 20 weeks, FBS is preferred over amniocentesis.

It is a life saving intervention when the fetus is affected with severe anaemia. The most common situation  is when the mother is Rh negative and the fetus is Rh positive. In about 1-2% of such pregnancies, the mother will produce antibodies (attacking proteins) that will go into the blood of the fetus and cause destruction of the red blood cells of the fetus. This makes the fetus anaemic and when it becomes severe, the anaemia can be lethal for the fetus. Correction of anaemia through direct fetal transfusion is the treatment of choice. Depending on the stage of pregnancy at which the fetus becomes anaemic the number of transfusions required might change. Typically the decision to do the procedure is taken after analysing various factors including what happened in a previous pregnancy, the blood flow velocity in the fetal brain vessel, and the stage of pregnancy.

In about 15% of single-placenta twins (monochorionic twins), there would be serious complications affecting one or both fetuses, that if left untreated would end up damaging both fetuses. During serial monitoring of the monochorionic twins, timely identification of such complications allow us to intervene at the correct time to avoid losing both babies. The aim of the interventions is to separate the two circulations as the babies sharing the blood might cause harm to one of both of them.This can be achieved by the use of fetoscopic LASER coagulation of the connecting vessels on the surface of the placenta or by  occluding the umbilical cord of one of the fetus using  radio frequency energy. Occlusion of the umbilical cord vessels results in the demise of that fetus while protecting the other fetus and is offered when the chances of saving two fetuses are low.

When fluid collects inside the fetal thorax, it is referred to as pleural effusion or hydrothorax. This fluid collection may increase in quantity within the fetal chest causing pressure effect on the heart and the main blood vessels leading to heart failure and ultimately fetal death. In such situations, insertion of a shunt tube that drains the fluid from within the chest to the outside of the fetus (i.e. into the amniotic sac) relieves the pressure and protects the baby from dying due to heart failure.