(591) Labor Progression in Women with SGA versus AGA Newborns

Thursday, January 30, 2025

4:00 PM – 6:00 PM

Submitting Author and Presenting Author(s)

Or Bercovich, BSc, MD

Rabin Medical Center
Petach Tikva, HaMerkaz, Israel

Coauthor(s)

DC

Daniela Chen, BSc, MD

Helen Schneider Hospital for Women, Rabin Medical Center, Petach-Tikva
Tel Aviv, HaMerkaz, Israel
Natav Hendin, MD

Rabin Medical Center
Petach Tikva, HaMerkaz, Israel
Shay Sukenik, MD

Beilinson
Tel Aviv, HaMerkaz, Israel
EH

Eran Hadar, MD

Rabin Medical Center
Petach Tikva, HaMerkaz, Israel
Ohad Houri, MD (he/him/his)

Doctor
Rabin Medical Center
Petach Tikva, HaMerkaz, Israel

Objective:

To compare labor progression in women with small for gestational age (SGA) newborns versus those with appropriate for gestational age (AGA) newborns.

Study Design:

Retrospective study at a tertiary university medical center from July 2012 to September 2020. Women with singleton pregnancies at or beyond 37 weeks of gestation were included. Exclusion criteria were multiple gestations, non-vertex presentations, previous multiple cesarean deliveries, and neonates with congenital anomalies, 5-minute Apgar < 7, or admission to the intensive care unit. The cohort was divided into SGA (birth weight < 10^th percentile) and AGA (birth weight 10-90^th percentile) newborns.

Interval-censored regression estimated median labor durations at each centimeter of cervical dilatation. Multivariate analyses adjusted for maternal age, BMI, and gestational age.

Results:

23,629 women were included, with 2,283 (9.66%) in the SGA group and 21,346 (90.33%) in the AGA group. In both primiparous and multiparous women, the duration of the first stage of labor (3-10cm dilatation) was not significantly different between the SGA and AGA groups, with medians of 4.45 (95^th percentile 13.31) vs. 4.65 hours (95^th percentile 12.27; P=0.54) in primiparous women and 2.49 (95^th percentile 9.73) vs. 2.72 hours (95^th percentile 9.34; P=0.88) in multiparous women, respectively. The active phase of labor (6-10cm dilatation) was shorter in primiparous women with SGA compared to AGA, with a median of 1.92 (95^th percentile 7.61) vs. 2.22 hours (95^th percentile 7.58; P< 0.01). However, no significant difference was observed in multiparous women, with medians of 0.64 hours (95^th percentile 4.08) vs. 0.84 hours (95^th percentile 4.45; P=0.95) in the SGA and AGA groups, respectively.

Conclusion:

Women with SGA and AGA newborns have a similar duration of labor overall. Although active phase of labor was statistically significantly shorter in primiparous women with SGA, the difference of 18 minutes is of limited clinical significance.