Hello XXXXXXX
Thanks for the query.
  your baby will not become acutely ill upon delivery.  Typically, if a baby does have a problem with a ventricular septal defect (VSD), they get out of breath with feeds and/or get sweaty with feeds some time within the first 2 months.  Then, we have medications that can help to decrease these symptoms.  The reason for this is to try to allow the babies to grow enough to restrict the blood flow across the defect.  At this time, it is difficult for me to say whether surgery will be required at all.  Your cardiologist will have to evaluate the baby's heart and the size of the VSD after birth.  Sometimes, muscular VSDs can close by themselves, as well.  Thus, babies do not necessarily require surgery at two months, or four months, or even at all.  I can say that, in a facility that does a lot of these, the outcomes are excellent with normal lifespans and the risks are quite minimal.
One third to one-half of all small VSDs close spontaneously (on their own). This seemingly miraculous event occurs most often before the baby is 1 year old, almost always before age 4 (75% by 2 years of age). The closure is due to the small VSD being located between heart fibers that increase in size in time, thus encroaching upon the opening in the ventricular septum.

Even if a small VSD does not close spontaneously, surgical repair is usually not recommended. However, long-term follow-up is required.

So please continue your pregnancy and there is no need to abort it.
I hope to have answered your query however you may revert to me for any further query.
Best of luck
Thanks

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