title: Early maternal serum ß-human chorionic gonadotropin (ß-hCG) levels and sex-related growth difference of IVF embryos.
abstract: OBJECTIVE
  Maternal serum ß-human chorionic gonadotropin (ß-hCG) represents the trophoblastic cell mass and is an indirect measurement of embryo development at early implantation stage. Studies in animals and human embryos detected sex-related growth differences (SRGD) in favour of male embryos during the pre-implantation period. The purpose of our study was to correlate SRGD and maternal serum ß-hCG at 16 days after embryo transfer.
  
  
  METHODS
  We retrospectively analysed all (fresh and frozen) non-donor, single embryo transfers (SET), elective and not elective, that were performed between December 2008 and December 2013. We included ß-hCG values from day 16 after oocyte collection of pregnancies resulting in live birth. Neonatal gender was retrieved from patient files. Male and female embryos were further grouped to cleavage and blastocyst stage transfers. Regression analysis for confounding variables included maternal age, maternal body mass index (BMI), use of micromanipulation (ICSI), embryo quality (grade), assisted hatching, day of transfer and fresh or frozen embryo transfer.
  
  
  RESULTS
  Seven hundred eighty-six non-donor SETs resulted in live birth. After including only day 16 serum ß-hCG results, 525 SETs were analysed. Neonatal gender was available for 522 cases. Mean maternal serum ß-hCG levels were similar, 347 ± 191 IU/L in the male newborn group and 371 ± 200 IU/L in the female group. The difference between ß-hCG levels remained insignificant after adjusting for confounding variables.
  
  
  CONCLUSIONS
  Early maternal ß-hCG levels after embryo transfers did not represent SRGD in our study.
authors: Department of Obstetrics and Gynecology, McGill University, MUHC Reproductive Center, Royal Victoria Hospital, 687 av des Pins West, Montreal, QC, H3A 1A1, Canada. esh.broder@gmail.com.
authors: Efrat
authors: http://orcid.org/0000-0003-4441-2341
authors: E
authors: Esh-Broder
authors: Department of Obstetrics and Gynecology, McGill University, MUHC Reproductive Center, Royal Victoria Hospital, 687 av des Pins West, Montreal, QC, H3A 1A1, Canada.
authors: Galia
authors: G
authors: Oron
authors: Department of Obstetrics and Gynecology, McGill University, MUHC Reproductive Center, Royal Victoria Hospital, 687 av des Pins West, Montreal, QC, H3A 1A1, Canada.
authors: Weon-Young
authors: WY
authors: Son
authors: Department of Obstetrics and Gynecology, McGill University, MUHC Reproductive Center, Royal Victoria Hospital, 687 av des Pins West, Montreal, QC, H3A 1A1, Canada.
authors: Hananel
authors: H
authors: Holzer
authors: Department of Obstetrics and Gynecology, McGill University, MUHC Reproductive Center, Royal Victoria Hospital, 687 av des Pins West, Montreal, QC, H3A 1A1, Canada.
authors: Togas
authors: T
authors: Tulandi
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000502:physiology*; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D007231:Infant, Newborn; D050498:Live Birth; D008297:Male; D008423:Maternal Age; D011247:Pregnancy; D012189:Retrospective Studies; D012737:Sex Factors; D056826:Single Embryo Transfer
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human
keywords: Embryo; IVF; Sex related; Sex-related growth difference; ß-hCG