Coding for VANISHING TWIN
A vanishing twin (or fetal resorption) is a fetus in a multi-gestation that fails to develop or dies in utero and is then partially or completely resorbed. Fetal numbering is most commonly determined by ultrasound. The baby positioned lowest in the uterus is usually given the designation of “Baby A.” Most commonly, Baby A will likely be born first in a vaginal delivery.In the case of a vanishing twin, the correct twin that vanished should be properly identified. In ICD-10 numbering, fetus 1 would indicate baby/fetus A, fetus 2 would be baby/fetus B, etc. When coding the continuing care of the pregnancy, the ICD-10 codes below are useful to indicate the fetus being evaluated.
O31.2 Continuing pregnancy after intrauterine death of one fetus or more
O31.20 Continuing pregnancy after intrauterine death of one fetus or more, unspecified trimester
O31.20X0 …… not applicable or unspecified
O31.20X1 …… fetus 1
O31.20X2 …… fetus 2
O31.20X3 …… fetus 3
O31.20X4 …… fetus 4
O31.20X5 …… fetus 5
O31.20X9 …… other fetus
O31.21 Continuing pregnancy after intrauterine death of one fetus or more, first trimester
O31.21X0 …… not applicable or unspecified
O31.21X1 …… fetus 1
O31.21X2 …… fetus 2
O31.21X3 …… fetus 3
O31.21X4 …… fetus 4
O31.21X5 …… fetus 5
O31.21X9 …… other fetus
O31.22 Continuing pregnancy after intrauterine death of one fetus or more, second trimester
O31.22X0 …… not applicable or unspecified
O31.22X1 …… fetus 1
O31.22X2 …… fetus 2
O31.22X3 …… fetus 3
O31.22X4 …… fetus 4
O31.22X5 …… fetus 5
O31.22X9 …… other fetus
O31.23 Continuing pregnancy after intrauterine death of one fetus or more, third trimester
O31.23X0 …… not applicable or unspecified
O31.23X1 …… fetus 1
O31.23X2 …… fetus 2
O31.23X3 …… fetus 3
O31.23X4 …… fetus 4
O31.23X5 …… fetus 5
O31.23X9 …… other fetus