The effect of labor and delivery on white blood cell count.
OBJECTIVE
To explore post-partum white blood cell (WBC) count, and possible factors affecting it.


METHODS
Retrospective cohort analysis of 12 079 healthy women, delivering a singleton term fetus with an uncomplicated course of labor, delivery and puerperium. All women delivered in a single tertiary, university-affiliated medical center from 2009 to 2014. Student's t-test, Mann-Whitney's U-test, χ(2) test and ANOVA were used to compare between variables. Multiple variable analyses was performed to allow adjustment for potential covariates and confounders. The main outcome measures included post-partum WBC count and the difference in the post-partum versus ante-partum WBC count, in association to mode of delivery, type of analgesia, timing of cesarean delivery and perineal trauma.


RESULTS
The mean post-partum WBC count was 13.39 ± .24 × 10(9)/L (range 1.20-37.30 × 10(9)/L). There is a significant increase in the WBC after delivery (2.1 9 ± 3.33 × 10(9)/L) with significant differences according to mode of delivery (2.34 ± 3.48, 3.32 ± 3.69 and 1.6 0 ± 2.87 × 10(9)/L for spontaneous, assisted and cesarean deliveries. Multiple variables can affect post-partum leukocytosis, including: age, parity, gestational age, mode of delivery, type of anesthesia, timing of cesarean delivery in relation to labor onset and the extent of perineal trauma.


CONCLUSIONS
Post-partum leukocytosis is a physiological phenomenon with a wide normal variation and multiple contributing factors. As a single parameter, post-partum leukocytosis should not prompt further work up.
a Helen Schneider Hospital for Women, Rabin Medical Center, and the Sackler Faculty of Medicine, Tel Aviv University , Tel Aviv , Israel.
Nissim
N
Arbib
a Helen Schneider Hospital for Women, Rabin Medical Center, and the Sackler Faculty of Medicine, Tel Aviv University , Tel Aviv , Israel.
Amir
A
Aviram
a Helen Schneider Hospital for Women, Rabin Medical Center, and the Sackler Faculty of Medicine, Tel Aviv University , Tel Aviv , Israel.
Rinat
R
Gabbay Ben-Ziv
a Helen Schneider Hospital for Women, Rabin Medical Center, and the Sackler Faculty of Medicine, Tel Aviv University , Tel Aviv , Israel.
Orly
O
Sneh
a Helen Schneider Hospital for Women, Rabin Medical Center, and the Sackler Faculty of Medicine, Tel Aviv University , Tel Aviv , Israel.
Yariv
Y
Yogev
a Helen Schneider Hospital for Women, Rabin Medical Center, and the Sackler Faculty of Medicine, Tel Aviv University , Tel Aviv , Israel.
Eran
E
Hadar
D000328:Adult; D000704:Analysis of Variance; D036861:Delivery, Obstetric / Q000379:methods*; D005260:Female; D006801:Humans; D007743:Labor, Obstetric / Q000097:blood*; D007958:Leukocyte Count; D007964:Leukocytosis / Q000097:blood*; D049590:Postpartum Period / Q000097:blood*; D011247:Pregnancy; D012189:Retrospective Studies; D012307:Risk Factors; D018709:Statistics, Nonparametric
Delivery; labor; leukocytosis; post-partum; white blood cells