Second-trimester maternal serum screening for Down syndrome in in vitro fertilization pregnancies.

Objectives: To examine whether second-trimester maternal serum triple marker screening results differ between in vitro fertilization (IVF) pregnancies and naturally conceived pregnancies.

Methods: Second-trimester maternal serum triple marker screening results from 88 IVF pregnancies were compared with 596 naturally conceived pregnancies (controls). Controls were matched to each IVF pregnancy by maternal age, gestational age and date of blood collection.