Abstract

OBJECTIVE:

To determine whether fetal size differences exist between matched fertile and infertile women and among women with infertility achieving pregnancy through various treatment modalities.

DESIGN:

Retrospective cohort study with propensity score analysis.

SETTING:

Tertiary care center and affiliated community hospitals.

PATIENT(S):

1,246 fertile and 461 infertile healthy women with singleton livebirths over a 10-year period.

INTERVENTION(S):

Infertile women conceiving without medical assistance, with ovulation induction, or with in vitro fertilization.

MAIN OUTCOME MEASURE(S):

Birthweight; secondary outcomes included crown-rump length, second-trimester estimated fetal weight, and incidence of low birth weight and preterm delivery.

RESULT(S):

Compared with matched fertile women, infertile women had smaller neonates at birth (3,375 ± 21 vs. 3,231 ± 21 g) and more low-birth-weight infants (relative risk = 1.68, 95% confidence interval, 1.06, 2.67). Neonates conceived via ovulation induction were the smallest among the infertility subgroups compared with the neonates of fertile women (3,092 ± 46 vs. 3,397 ± 44 g). First-trimester fetal size was smaller in infertile versus fertile women (crown-rump length 7.9 ± 0.1 vs. 8.5 ± 0.1 mm). Within the infertility subgroups, no differences in fetal or neonatal size were found.

CONCLUSION(S):

The inherent pathologic processes associated with infertility may have a larger impact on fetal growth than infertility therapies.

Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.