[citation needed] The mother will usually have high levels of specific proteins including maternal serum alpha-fetoprotein (AFP) and beta-human chorionic gonadotropin (hCG).

[medical citation needed] Infants may show facial abnormalities, micrognathia, cleft lip, spina bifida, as well as other birth defects that result from kidney, limb, and umbilical cord complications.

[medical citation needed] Triploidy may be suggested by dramatically elevated levels of serum alpha-fetoprotein.

On obstetric ultrasonography, abnormalities of the skeleton, central nervous system, heart, abdomen, and kidneys are visible in the most severe cases beginning at 12-14 weeks of pregnancy.

Placentomegaly or intrauterine growth restriction are the typical findings that prompt evaluation for triploidy, though oligohydramnios may be the first sign in some cases.

If triploidy is diagnosed during the pregnancy, termination is often offered as an option due to the additional health risks for the mother (pre-eclampsia, a life-threatening condition, or choriocarcinoma, a type of cancer).

Should a mother decide to carry until term or until a spontaneous miscarriage occurs, doctors will monitor her closely in case either condition develops.

[citation needed] Mosaic triploidy has an improved prognosis, but affected individuals have moderate to severe cognitive disabilities.