MORE INFO: Studies have shown that women older than 45 or 50 have good pregnancy outcomes. In 2005, 14.4 percent of all births in the U.S. were to women older than 35. There were 417 births to women aged 50-54. Risks increase for chromosomal abnormalities, congenital malformations, ectopic pregnancies, spontaneous abortion, placenta previa, preeclampsia hospitalization, cesarean delivery and other complications when the mother is older than 35. The possibility to develop hypertension and diabetes is also a risk.