Time-to-pregnancy and offspring finger-length ratio (2D:4D)
- DOI
- Language of the publication
- English
- Date
- 2018-10-17
- Type
- Article
- Author(s)
- Shere, Mahvash
- Arbuckle, Tye E.
- Monnier, Patricia
- Fraser, William
- Velez, Maria P.
- Publisher
- Wiley
Abstract
Objectives Time-to-Pregnancy (TTP) is an epidemiological tool to assess couple fecundity. The finger digit ratio (2D:4D) has been suggested as a marker of androgen exposure in utero. Maternal, paternal, or couple-mediated factors related to fecundity may also have an effect on androgen exposure during pregnancy. We aimed to investigate the association between TTP, infertility, or use of Assisted Reproductive Technologies (ART) and offspring 2D:4D. Methods Data from 673 mother-child pairs were collected from questionnaires in the Maternal-Infant Research on Environmental Chemicals (MIREC) study across 10 cities in Canada. The mean maternal age was 33.4 years (SD 4.7), with a median gestational age of 12.1 weeks (SD 1.3), at the time of recruitment. Our study included 338 girls and 335 boys, and the mean age of the children at follow-up was 3.5 years (SD 1.0). TTP was assessed through questionnaires during the first trimester of pregnancy. Digital photographs of both hands were taken in a follow-up study to calculate the children's 2D:4D (2–5 years). anova, t tests, and multiple linear regression analyses were conducted. Results Boys had significantly lower mean 2D:4Ds (0.936 ±0.041 in right hand, 0.936 ±0.040 in left hand) compared to girls (0.948 ±0.038 in right hand, 0.945 ±0.038 in left hand). The mean 2D:4D did not differ according to TTP, infertility, or use of ART. The only factors associated with the child's 2D:4D were the child's age and maternal 2D:4D. Conclusions Our study does not support an association between TTP, infertility, or use of ART and children's 2D:4D.
Plain language summary
Health Canada helps to protect the health of Canadians by assessing and managing the risks associated with exposure to environmental chemicals. To predict the reproductive toxicity of hormone-disrupting chemicals, two markers have been suggested. One marker is to measure the lengths of the 2nd and 4th fingers and then calculate the ratio (2D:4D). Some researchers think that a person’s 2D:4D ratio is a marker of greater exposure to the male hormone androgen during fetal development as boys tend to have lower 2D:4D ratios than girls. The number of months it takes for a couple to get pregnant (time to pregnancy) is another marker used to study fertility. Whether these two markers are related to each other is not known. Data from 673 mother-child pairs were collected in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study. Women in the study were asked the number of months it took them to get pregnant with the current pregnancy. Digital photographs of both hands were taken to calculate 2D:4D for the woman and her child (at 2-5 years of age). Various statistical techniques were used to study the association between time to pre"Health Canada helps to protect the health of Canadians by assessing and managing the risks associated with exposure to environmental chemicals. To predict the reproductive toxicity of hormone-disrupting chemicals, two markers have been suggested. One marker is to measure the lengths of the 2nd and 4th fingers and then calculate the ratio (2D:4D). Some researchers think that a person’s 2D:4D ratio is a marker of greater exposure to the male hormone androgen during fetal development as boys tend to have lower 2D:4D ratios than girls. The number of months it takes for a couple to get pregnant (time to pregnancy) is another marker used to study fertility. Whether these two markers are related to each other is not known. Data from 673 mother-child pairs were collected in the Maternal-Infant Research on Environmental Chemicals (MIREC) Study. Women in the study were asked the number of months it took them to get pregnant with the current pregnancy. Digital photographs of both hands were taken to calculate 2D:4D for the woman and her child (at 2-5 years of age). Various statistical techniques were used to study the association between time to pregnancy, infertility, or use of assisted reproductive technologies (ART), and children’s 2D:4D. The results showed that boys had significantly lower 2D:4D compared to girls, but that there was no association between 2D:4D and time to pregnancy or any measure of fertility. The only factors associated with the child’s 2D:4D were the child’s age and the woman’s 2D:4D. In agreement with other studies, this study found that boys had lower digit ratios compared to girls, but suggests that 2D:4D may not be related to infertility. " gnancy, infertility, or use of assisted reproductive technologies (ART), and children’s 2D:4D. The results showed that boys had significantly lower 2D:4D compared to girls, but that there was no association between 2D:4D and time to pregnancy or any measure of fertility. The only factors associated with the child’s 2D:4D were the child’s age and the woman’s 2D:4D. In agreement with other studies, this study found that boys had lower digit ratios compared to girls, but suggests that 2D:4D may not be related to infertility.
Subject
- Health,
- Health and safety