Fetal sex-specific differences in gestational age at delivery in pre-eclampsia: a meta-analysis

• Published in: International journal of epidemiology Vol. 46; no. 2; pp. 632 - 642
• Main Authors: Schalekamp-Timmermans, Sarah, Arends, Lidia R, Alsaker, Elin, Chappell, Lucy, Hansson, Stefan, Harsem, Nina K, Jälmby, Maya, Jeyabalan, Arundhathi, Laivuori, Hannele, Lawlor, Debbie A, Macdonald-Wallis, Corrie, Magnus, Per, Myers, Jenny, Olsen, Jørn, Poston, Lucilla, Redman, Christopher W, Staff, Anne C, Villa, Pia, Roberts, James M, Steegers, Eric A
• Format: Journal Article
• Language: English
• Published: England Oxford University Press 01-04-2017
• Subjects: Adult; ALSPAC; Clinical Medicine; Delivery, Obstetric - statistics & numerical data; Female; Fetal Development; Fetal Growth Retardation - epidemiology; Gestational Age; Humans; Infant, Newborn; Klinisk medicin; Male; Medical and Health Sciences; Medicin och hälsovetenskap; Obstetrics, Gynecology and Reproductive Medicine; Placenta; Pre-eclampsia; Pre-Eclampsia - epidemiology; Pregnancy; Pregnancy Complications - epidemiology; Reproduktionsmedicin och gynekologi; Sex Factors; Sex ratio; Sexual dimorphism; Women’s Health; Young Adult; placenta; ALSPAC; pre-eclampsia; Sexual dimorphism; sex ratio
• ISSN: 0300-5771; 1464-3685
• DOI: 10.1093/ije/dyw178

: Pre-eclampsia (PE) is a major pregnancy disorder complicating up to 8% of pregnancies. Increasing evidence indicates a sex-specific interplay between the mother, placenta and fetus. This may lead to different adaptive mechanisms during pregnancy.
We performed an individual participant data meta-analysis to determine associations of fetal sex and PE, with specific focus on gestational age at delivery in PE. This was done on 219 575 independent live-born singleton pregnancies, with a gestational age at birth between 22.0 and 43.0 weeks of gestation, from 11 studies participating in a worldwide consortium of international research groups focusing on pregnancy.
Of the women, 9033 (4.1%) experienced PE in their pregnancy and 48.8% of the fetuses were female versus 51.2% male. No differences in the female/male distribution were observed with respect to term PE (delivered ≥ 37 weeks). Preterm PE (delivered < 37 weeks) was slightly more prevalent among pregnancies with a female fetus than in pregnancies with a male fetus [odds ratio (OR) 1.11, 95% confidence interval (CI) 1.02-1.21]. Very preterm PE (delivered < 34 weeks) was even more prevalent among pregnancies with a female fetus as compared with pregnancies with a male fetus (OR 1.36, 95% CI 1.17-1.59).
Sexual dimorphic differences in the occurrence of PE exist, with preterm PE being more prevalent among pregnancies with a female fetus as compared with pregnancies with a male fetus and with no differences with respect to term PE.