Differences in Fetal Growth, Discordancy, and Placental Pathology in Reduced versus Nonreduced Twins

ABSTRACT

This study evaluated the effect of multifetal pregnancy reduction on the incidence of small for gestational age (SGA) and discordance in reduced versus nonreduced twins and differences in placental pathology. A computerized ultrasound database was used to identify diamniotic-dichorionic twins who delivered at our institution. Reduced (n = 36) versus nonreduced twins (n = 243) were compared for differences in rates of SGA and discordancy (≥ 20%.) The groups were compared for differences in maternal and neonatal characteristics, as well as differences in placental pathology. Chi-square tests were used to compare differences in means. Stepwise logistic regression was used to adjust for potential confounders including placental pathology. The rate of SGA in either twin A or B remained nonsignificant after adjustment for the use of assisted reproductive technology and gestational age at delivery in the stepwise logistic model (odds ratio, 1.7 95%; confidence interval, 0.5, 5.2). The average discordance at delivery was 12.4% in reduced versus 11.4% in the nonreduced twins (p = 0.54). We found no overall differences in placental pathology between the two groups. Reduced and nonreduced twins have no significant differences in SGA fetuses, growth discordancy, or placental pathology.

KEYWORDS

Multifetal pregnancy reduction - fetal growth - discordancy - placental pathology

REFERENCES

• 1 Keith L G, Oleszcuk J J, Keith D M. Multiple gestation: reflections on epidemiology, causes and consequences.  Int J Fertil Womens Med. 2000;  45 206-214
• 2 Martin J A, Hamilton B E, Sutton P D, Ventura S J, Menacker F, Kirmeyer S. Births: final data 2004.  Natl Vital Stat Rep. 2006;  55 1-101
• 3 Powers W F, Kiely J L. The risks confronting twins: a national perspective.  Am J Obstet Gynecol. 1994;  170 456-461
• 4 Sibai B M, Hauth J, Caritis S et al.. Hypertensive disorders in twins versus singleton gestations. National Institute of Child Health and Human Development Network of Maternal Fetal Medicine Units.  Am J Obstet Gynecol. 2000;  182 938-942
• 5 Multiple Gestation . Complicated twin, triplet and high-order multifetal pregnancy.  ACOG Practice Bulletin. 2004;  , #56
• 6 Torok O, Lapinski R, Salafia C M, Bernasko J, Berkowitz R L. Multifetal pregnancy reduction is not associated with an increased risk of intrauterine growth restriction, except for very high order multiples.  Am J Obstet Gynecol. 1998;  179 221-225
• 7 Audibert F, Boullier M, Boithias C, Kerbrat V, Vial M, Frydman R. Embryo reduction and birth weight discordance in dichorionic twins.  Hum Reprod. 2003;  18 437-440
• 8 Depp R, Macones G A, Rosenn M F, Turzo E, Wapner R J, Weinblatt V J. Multifetal pregnancy reduction: evaluation of fetal growth in the remaining twins.  Am J Obstet Gynecol. 1996;  174 1233-1240
• 9 Lembet A, Selam B, Gaddipati S, Berkowitz R L, Salafia C M. Shortened gestational age following multifetal pregnancy reduction: can chronic placental inflammation be the explanation?.  J Matern Fetal Med. 2001;  10 149-154
• 10 Papageorghiou A T, Vigdou k, Bakoulas V, Sebire N J, Nicolaides K H. Risks of miscarriage and early preterm birth in trichorionic triplet pregnancies with embryo reduction versus expectant management: new data and systematic review.  Hum Reprod. 2006;  21 1912-1917
• 11 Berkowitz R L, Lynch L, Lapinski R, Bergh P. First trimester transabdominal multifetal pregnancy reduction: a report of 200 complete cases.  Am J Obstet Gynecol. 1993;  169 17-27
• 12 Ananth C V, Vintzileos A M, Shen-Schwarz S, Smulian J C, Lai Y L. Standards of birth weight in twin gestations stratified by placental chorionicity.  Obstet Gynecol. 1998;  91 917-924
• 13 American College of Obstetricians and Gynecologists .Special problems of multiple gestation. The College, Washington (DC); (1998) Educational bulletin No.: 253
• 14 Yaron Y, Bryant-Greenwood P K, Dave N et al.. Multifetal pregnancy reductions of triplets to twins: comparison with nonreduced triplets and twins.  Am J Obstet Gynecol. 1999;  180 1268-1271
• 15 Silver R K, Helfand B T, Russell T L, Ragin A, Sholl J S, MacGregor S N. Multifetal reduction increases the risk of preterm delivery and fetal growth restriction in twins: a case-control study.  Fertil Steril. 1997;  67 30-33
• 16 Alexander J M, Hammond K R, Steinkampf M P. Multifetal reduction of high-order multiple pregnancy: comparison of obstetrical outcome with nonreduced twin gestations.  Fertil Steril. 1995;  64 1201-1203