If, at delivery, the genitalia are ambiguous to the midwife and/or doctor (this happens to between 1 in 1000 to 1 in 10000 live births), it is somewhat important not to make a definitive statement regarding the infant's sex straight away. Extra time should be taken for further investigation - if still in doubt, a karyotype should tell the infant's genotypic gender.
Counselling should be offered to the parents and options given as to what they can do with their newborn and how to raise it (i.e. as which sex).