Department of Obstetrics and Gynaecology, Lagos University Teaching Hospital, Lagos. Tel: +1(431) 668-3320; Email:
Faculty of Clinical Sciences, College of Medicine, University of Lagos, Lagos.
West Afr J Med. 2024 Jul 30;41(7):818-825.
Until now, the sex ratio in a population is believed to be relatively stable with no male/female preponderance. There has been an increasing amount of evidence to suggest that assisted conception may significantly impact on sex ratio (SR). Several factors have been suggested to affect SR such as parental variables (paternal race, maternal age, and body mass index-(BMI), methods of fertilisation (in-vitro fertilisation/intracytoplasmic sperm injection), stage of embryo transfer (cleavage/blastocyst), type of IVF cycle (fresh/cryopreserved), medications used for controlled ovarian stimulation, poor sperm motility, and even culture media.
This study aims to investigate the potential impact of the different ART procedures on sex ratio. It will also explore the relationship between paternal race, maternal age and body mass index BMI on sex ratio.
A retrospective cohort study from January 2017 to December 2023. Participants were women who had successful ART and delivery at Ninewells Assisted Conception Unit (NACU) Dundee and ART centre of Lagos University Teaching Hospital, Nigeria.
Overall, 294 (66.2%) of the case records and 150 (33.8%) were evaluated from NACU and LUTH respectively. More male infants 244 (66.8%) were delivered following pregnancies conceived with blastocyst embryo stage transfer when compared with female infants which stood at 121 (33.2%). Concerning cleavage embryo stage transfer, 56 (70.9%) were in favour of female newborns while males accounted for 23 (29.1%).
The study revealed that there is an increase in the proportion of male babies born following certain assisted conception techniques such as blastocyst stage embryo transfer and IVF while more female babies were born when cleavage stage embryos were transferred or when ICSI was used as a method of fertilisation.
到目前为止，人们认为人口中的性别比例相对稳定，没有男性/女性优势。越来越多的证据表明，辅助受孕可能会对性别比例（SR）产生重大影响。已经有几个因素被认为会影响 SR，例如父母变量（父系种族、母亲年龄和体重指数（BMI））、受精方法（体外受精/胞浆内精子注射）、胚胎移植阶段（卵裂/囊胚）、IVF 周期类型（新鲜/冷冻）、用于控制性卵巢刺激的药物、精子活动力差，甚至培养介质。
本研究旨在探讨不同的 ART 程序对性别比例的潜在影响。它还将探讨父系种族、母亲年龄和体重指数 BMI 与性别比例之间的关系。
这是一项回顾性队列研究，时间为 2017 年 1 月至 2023 年 12 月。参与者为在英国邓迪的 Ninewells 辅助受孕单位（NACU）和尼日利亚拉各斯大学教学医院的 ART 中心成功进行 ART 并分娩的女性。
总体而言，NACU 和 LUTH 分别评估了 294 份（66.2%）病历和 150 份（33.8%）病历。与囊胚胚胎阶段转移相比，更多的男性婴儿（244 例，66.8%）在妊娠中分娩，而女性婴儿为 121 例（33.2%）。在卵裂胚胎阶段转移方面，56 例（70.9%）有利于女婴出生，而男婴则有 23 例（29.1%）。
该研究表明，某些辅助受孕技术，如囊胚阶段胚胎转移和 IVF，会增加男婴的比例，而当转移卵裂期胚胎或使用 ICSI 作为受精方法时，会有更多的女婴出生。
