थैलासीमिया की counselling. pre pregnancyPGT-M, prenatal diagnosis

थैलासीमिया को आप रोक सकते हैं, किस प्रकार का थैलासीमिया है, genetic mutation कोनसा है, का ज्ञान होना बोहुत जरूरी है।   Many a times we come across the following scenarios: A child is born in a family and suddenly the couple finds that it is affected by " Mongolism" or Down syndrome, which they never thought of . A child is born and it is very healthy and grows well, but after 6 or 7 months, the child suffers from severe anemia and when they contact the paediatrician, it is found to be "beta-Thalassemia-Major''. Doctors tell them that this disease can not be cured completely, but you can continue the life of the child by regular blood transfusion. How many families can afford this therapy... sometimes they lose all their money and if not well cared, the baby dies. A newborn suddenly develops a symptom: like sudden vomiting, convulsions or becoming blue and within days the baby collapses and dies. Doctors are baffled by the symptoms and can not make the diagnosis. Can we assure this couple, that your next child will be safe and will not suffer from the disease the earlier one suffered. If we wish to help them, then we have to do something in their next pregnancy at the, so that we can catch or identify the disease. Now if this couple wants to take any decision about this pregnancy, the lady will have least psychological trauma Any intervention or treatment to the unborn baby to identify or treat the disease: The science is called Fetal Medicine. That means we treat the fetus as an identity or an individual. Looking at the above scenario there are following things we can perform to help the pregnant individual and the family. 1. Genetic Counselling, very important step to explain the couple the pros and cons of the procedures. 2. Aneuploidy screening : Looking for the chromosomal status of the fetus, like extra set of chromosome Number 21 or 13 or 18 and sex chromosome, or some missing set of chromosome. It is done by double marker at 10 to 12 weeks. It gives us an idea and should be confirmed by diagnostic methods. 3. First trimester Nuchal Translucency scan: Gives an idea about the aneuploidy and anatomical structure of the fetus at an early stage of pregnancy, around 12 weeks. 4. A targeted imaging of the fetus at 16 to 20 weeks to identify any abnormality and imprints of genetic defects. 5. Quat marker testing : Another way of screening by maternal blood for chromosomal defects at 16 to 18 week. We should take all pregnancies at risk of aneuploidy until proved otherwise. But there are pregnancies when there is some disease ( not chromosomal but inside the chromosome, that is defect in the printing of DNA, the Genetic disorders,) going in there families, like thalassemia, sickle cell disease etc,  and the couple comes to us with a question “ Sir/ Madam, can we have a baby not carrying the same disease which my previous child is/was suffering” Or they may come to us “ We both are carriers of some disease, but we are not symptomatic, will our child suffer from the symptomatic disorder” These can be answered only by examining the “The Fetus” itself (Chromosomal disorder (aneuploidy) or genetic disorders). Here we have to get some cells/tissues from the fetus. It may be done at 12 weeks, by Chorion villus sampling(CVS) or at 16-18 weeks by Amniocentesis. As they are invasive diagnostic tests, they carry the risk of losing the pregnancy, although to a very less extent ( one out of 500 to 1000 cases). Non-invasive prenatal test(NIPT/S) may be one of the answers. When we call it a “Test” then it should be diagnostic and the couple should take decision on its result. Unfortunately, till today, this is not the case. The NIPT/NIPS is still suffering from lots of shortcomings and is still under research.   Pre-implantation diagnosis for chromosomal and genetic diseases ( Pre-implantation genetic testing for aneuploidy PGT-A, for monogenic disorders PGT-M, and for structural rearrangements PGT-SR,)  is growing in leaps and bounds. It will help the family to start the pregnancy with “Confirmed healthy fetus”. But till today, we have to validate its findings by doing prenatal diagnostic procedures like CVS or Amniocentesis. And top of it, it requires an extra effort of In-vitro fertilization and embryo freezing, with all its shortcomings. At present, the gold standard to confirm the fetal disorder is by either Chorionic Villus sampling or Amniocentesis. These fetal cells are subjected to regular karyotyping, molecular karyotyping, Chromosomal Microarray, SNP microarray, clinical exome sequencing or whole genome sequencing, depending on the need. The future goal will always remain: Can we get all the information at the earliest stage of pregnancy without harming the health of the fetus. The earliest is the diagnosis, least will be the trauma to the lady and the family.       Dr.D'Pankar Banerji MS ( ObGy) Consulting Gynecologist and IVF specialist www.drbanerji-fertilityclinic.com