TY - JOUR
T1 - The risk of secondary sex ratio imbalance and increased monozygotic twinning after blastocyst transfer
T2 - Data from the Japan Environment and Children's Study
AU - Hattori, Hiromitsu
AU - Kitamura, Akane
AU - Takahashi, Fumiaki
AU - Kobayashi, Norio
AU - Sato, Akiko
AU - Miyauchi, Naoko
AU - Nishigori, Hidekazu
AU - Mizuno, Satoshi
AU - Sakurai, Kasumi
AU - Ishikuro, Mami
AU - Obara, Taku
AU - Tatsuta, Nozomi
AU - Nishijima, Ichiko
AU - Fujiwara, Ikuma
AU - Kuriyama, Shinichi
AU - Metoki, Hirohito
AU - Yaegashi, Nobuo
AU - Nakai, Kunihiko
AU - Arima, Takahiro
AU - Kawamoto, Toshihiro
AU - Saito, Hirohisa
AU - Kishi, Reiko
AU - Hashimoto, Koichi
AU - Mori, Chisato
AU - Hirahara, Fumiki
AU - Yamagata, Zentaro
AU - Inadera, Hidekuni
AU - Kamijima, Michihiro
AU - Konishi, Ikuo
AU - Iso, Hiroyasu
AU - Shima, Masayuki
AU - Ogawa, Toshihide
AU - Suganuma, Narufumi
AU - Kusuhara, Koichi
AU - Katoh, Takahiko
N1 - Funding Information:
The Japan Environment and Children’s Study is funded by the Ministry of the Environment of the Government of Japan. The members of the Japan Environment and Children’s Study (JECS) as of 2016 were as follows; Toshihiro Kawamoto (principal investigator), Hirohisa Saito (National Center for Child Health and Development, Tokyo, Japan), Reiko Kishi (Hokkaido University, Sapporo, Japan), Nobuo Yaegashi (Tohoku University, Sendai, Japan), Koichi Hashimoto (Fukushima Medical University, Fukushima, Japan), Chisato Mori (Chiba University, Chiba, Japan), Fumiki Hirahara (Yokohama City University, Yokohama, Japan), Zentaro Yamagata (University of Yamanashi, Chuo, Japan), Hidekuni Inadera (University of Toyama, Toyama, Japan), Michihiro Kamijima (Nagoya City University, Nagoya, Japan), Ikuo Konishi (Kyoto University, Kyoto, Japan), Hiroyasu Iso (Osaka University, Suita, Japan), Masayuki Shima (Hyogo College of Medicine, Nishinomiya, Japan), Toshihide Ogawa (Tottori University, Yonago, Japan), Narufumi Suganuma (Kochi University, Nankoku, Japan), Koichi Kusuhara (University of Occupational and Environmental Health, Kitakyushu, Japan), Takahiko Katoh (Kumamoto University, Kumamoto, Japan).
Funding Information:
JECS was funded by the Japanese Ministry of the Environment. The findings and conclusions of this article are solely the responsibility of the authors and do not represent the official views of the government.
PY - 2019/2/22
Y1 - 2019/2/22
N2 - Background: Some studies have suggested that blastocyst transfer is associated with i) imbalance in the secondary sex ratio (SSR) (which favors male offspring), ii) increased incidence of monozygotic twins (MZT). In contrast, others have not found these changes. In this study, we evaluated the association between blastocyst transfer and SSR and MZT, considering potential parental confounders. Methods: The Japan Environment and Children's Study is a large, nationwide longitudinal birth cohort study funded by the Ministry of the Environment of Japan. We used this large dataset, including 103,099 pregnancies, to further investigate the association between blastocyst transfer, SSR and MZT, using spontaneously conceived pregnancies, non-assisted reproductive technology (non-ART) treatment (intrauterine insemination and ovulation induction with timed intercourse) and cleavage stage embryo transfer for comparison. We evaluated the association with each group, the SSR, and the frequency of MZT, calculating the adjusted odds ratio (AOR) using multivariable logistic regression analyses, adjusting for potential parental confounders such as basic health and socioeconomic status. Results: For each group (spontaneous conception vs. non-ART treatment vs. cleavage stage embryo transfer vs. blastocyst transfer), the percentages of males were 51.3% vs 50.7% vs 48.9% vs 53.4% and the monozygotic twinning rates per pregnancy were 0.27% vs 0.11% vs 0.27% vs 0.99% respectively. Multivariate logistic regression analyses indicated that blastocyst transfer was significantly associated with a higher SSR and higher incidence of MZT than the other three groups (SSR: AOR 1.095, 95% CI1.001-1.198; MZT: AOR 4.229, 95% CI 2.614-6.684). Conclusions: There are significant relationships between blastocyst transfer and SSR imbalance and a higher occurrence of MZT.
AB - Background: Some studies have suggested that blastocyst transfer is associated with i) imbalance in the secondary sex ratio (SSR) (which favors male offspring), ii) increased incidence of monozygotic twins (MZT). In contrast, others have not found these changes. In this study, we evaluated the association between blastocyst transfer and SSR and MZT, considering potential parental confounders. Methods: The Japan Environment and Children's Study is a large, nationwide longitudinal birth cohort study funded by the Ministry of the Environment of Japan. We used this large dataset, including 103,099 pregnancies, to further investigate the association between blastocyst transfer, SSR and MZT, using spontaneously conceived pregnancies, non-assisted reproductive technology (non-ART) treatment (intrauterine insemination and ovulation induction with timed intercourse) and cleavage stage embryo transfer for comparison. We evaluated the association with each group, the SSR, and the frequency of MZT, calculating the adjusted odds ratio (AOR) using multivariable logistic regression analyses, adjusting for potential parental confounders such as basic health and socioeconomic status. Results: For each group (spontaneous conception vs. non-ART treatment vs. cleavage stage embryo transfer vs. blastocyst transfer), the percentages of males were 51.3% vs 50.7% vs 48.9% vs 53.4% and the monozygotic twinning rates per pregnancy were 0.27% vs 0.11% vs 0.27% vs 0.99% respectively. Multivariate logistic regression analyses indicated that blastocyst transfer was significantly associated with a higher SSR and higher incidence of MZT than the other three groups (SSR: AOR 1.095, 95% CI1.001-1.198; MZT: AOR 4.229, 95% CI 2.614-6.684). Conclusions: There are significant relationships between blastocyst transfer and SSR imbalance and a higher occurrence of MZT.
KW - Blastocyst transfer
KW - Japan Environment and Children's Study
KW - Monozygotic twins
KW - Secondary sex ratio
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U2 - 10.1186/s12958-019-0471-1
DO - 10.1186/s12958-019-0471-1
M3 - Article
C2 - 30795788
AN - SCOPUS:85062026618
VL - 17
JO - Reproductive Biology and Endocrinology
JF - Reproductive Biology and Endocrinology
SN - 1477-7827
IS - 1
M1 - 27
ER -