Why is blood group important in a marriage?

Rh factor is an antigen present on the red blood cells. Depending on whether it is present or not people are designated Rh +ve or Rh -ve.

A woman is at risk when her blood group is Rh-ve and that of her partner is Rh+ve. This combination can produce a child who is Rh+ve. Though the mother's and baby's blood systems are separate there are times when the blood from the baby can enter into the mother's system. This can cause the mother to create antibodies against the Rh factor, thus treating an Rh+ve baby like an intruder in her body. This could complicate the delivery.

Rh Factor Possiblities

Father's Group	Mother's Group	(Child's possible Group)
Rh+	Rh+	(Rh+ or Rh-)
Rh+	Rh-	(Rh+ or Rh-)
Rh-	Rh+	(Rh+ or Rh-)
Rh-	Rh-	(Rh-)

However, with the improving medical research these days, this problem is avoidable with the use of injections, which are administered to the mother-to-be during 28th week of pregnancy and immediately after the delivery. There are more complex treatments for severe cases, though they are not required mostly. If you have more questions on Rh factor, do not hesitate to consult with your doctor.