welcome to HealthcareMagic
At 6 months there is no medical abortion
and it will be like a proper delivery.The main thing you said is that you fear that your baby will suffer birth defect
so was it told by a doctor after confirming it with sonography
or is it just because you feel so you want to get aborted.If you have not done sonography i would suggest you to get the scan done for birth defect and then consult a Gynaecologist for opinion and treatment.