Q: I've had multiple miscarriages, and my doctor said it could be due to a translocation in the chromosomes. What exactly is this?
A: Chromosomes are the vessels that carry your DNA. When a baby is conceived, she normally would receive 23 chromosomes from her mom's egg and 23 from her dad's sperm, for a total of 46. These chromosomes pair up and begin the process of helping your baby grow. But sometimes they don't sync up in even groups of two, which results in a genetic abnormality called a translocation. If there are still 46 chromosomes total, the child will likely be healthy, but a problem can arise if she one day tries to conceive with someone else who also has a translocation.
If one partner has a translocation, and conceives with a partner who doesn't, the baby will be fine. However, if both parents have the condition, it can sometimes -- but not always -- lead to miscarriage.
- If, for example, you pass on 22 chromosomes to your baby and your partner passes down 24, they'll balance each other out and result in a normal, 46-chromosome baby.
- But if you pass on 22 and your partner passes on 22, say, then your unborn baby would inherit just 44 chromosomes, and would not survive.
You and your husband can have your genes tested to see if either of you carries a translocation. If it turns out that you both have the condition, you can still get pregnant and have a healthy baby with assisted reproductive technology techniques like preimplantation genetic diagnosis (PGD). Here, your egg is fertilized by your partner's sperm in a lab setting through in vitro fertilization (IVF). The embryos are then screened to see whether they have the normal number of chromosomes, and only the healthiest ones are implanted in your uterus.