Association between Blood hCG Elevation Rate in Very Early IVF Pregnancy and Adverse Pregnancy Outcome

Inbal Navon Avital Wertheimer Alyssa Hochberg-Amikam Onit Sapir Avi Ben Haroush Eran Altman Noam Domnitz Tzippy Shochat Yoel Shufaro
Infertility and IVF Unit, Helen Schneider Hospital for Women, Rabin Medical Center, Israel

Aim:
Abnormal hCG elevation patterns have been strongly associated with short-term adverse pregnancy outcomes such as miscarriage, early fetal demise and ectopic pregnancies. However, the long-term impact of slow hCG elevation rate on pregnancies that do continue to term is unknown.

Methods:
Single center retrospective cohort study of 703 fresh cycles resulting in live singleton birth. The first blood hCG measurement was performed 14±1.4 days after OPU, and the second one 48-72h later. The slope between the two measurements was calculated and adjusted per day. Slow hCG elevation was defined as a slope value below the 10th percentile. Pregnancy outcomes were compared between cycles with a slow elevation and a “normal” elevation in hCG values.

Results:
There were no differences between the groups in maternal age, numbers of retrieved oocytes, ICSI rates, number of transferred and usable embryos, and gestational age at delivery. Neonates from cycles with a slow hCG elevation weighed significantly less (2876±619 gr vs. 3083±553 gr, p<0.005) and were at a higher risk (21% vs. 12%, OR=1.96, 95% CI 1.06-3.64) of having low birth weights (<2500grams). Women with slow hCG elevation rate had more hypertension-preeclampsia related complications (11% vs. 6%, p<0.05), although barely reaching statistical significance in the multivariate analysis (OR=1.76, 95% CI 1.0-3.6).

Discussion:
Early blood hCG elevation slope might be a novel marker for identifying patients at risk for hypertensive complications during pregnancy and low birth-weight. Tighter prenatal care for these pregnancies could potentially improve pregnancy outcome and reduce long-term complications.