Increased chance of giving birth before 37 weeks
(premature delivery), which poses greater risks of illness, disability, and
death. For more information, see the topics Preterm Labor and Premature
Differences in size between the fetuses
(discordance), usually from twin-to-twin transfusion. In twin-to-twin
transfusion, blood shifts from one fetus (the donor) through the placenta to
the other fetus (the recipient).
Increased risk of birth defects
and genetic disorders. For more information, see the topic Multiple Pregnancy:
Twins or More.
The delivery and care of multiple infants is costly,
especially if they have special needs, which often is the case with babies born
If a woman becomes pregnant with several fetuses, she
and her partner may choose
selective reduction (multifetal pregnancy reduction).
This procedure removes one or more of the embryos during the first trimester,
giving the remaining fetuses a better chance of healthy survival. But the procedure also has a risk of ending the pregnancy.