Aging of fertilizing gametes and spontaneous abortion

Guerrero, Rodrigo; Lanctot, Claude A.

doi:10.1016/0002-9378(70)90595-8

Cited by 23 publications

(4 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The "U"-shaped configuration of SSR and pathologic progeny vis-à-vis timing of ovulation. The tendencies toward disproportionate attrition and loss of conceptuses at the very beginning and very end of the fertility window versus optimal survival at the middle of the window are in line with the "U"shaped configuration in relation to the estimated ovulation date for conceptions that are destined to end in spontaneous abortion (29). In addition, these tendencies explain the other well-known "U"-shaped probabilities for delivering male offspring vis-à-vis timing of insemination in various animals or estimated ovulation in humans: insemination at the time of ovulation apparently biases the SSR in favor of equal sex proportions, in contrast to a moderate increase in males before or after ovulation (for pooled data, 94:100 vs. 117:100) (30).…”

Section: Compatible With the Hypothesis That The Decrease In The Ratimentioning

confidence: 57%

The Secular Trends in Male:Female Ratio at Birth in Postwar Industrialized Countries

Jongbloet¹,

Zielhuis²,

Groenewoud³

et al. 2001

Environmental Health Perspectives

View full text Add to dashboard Cite

Section: Compatible With the Hypothesis That The Decrease In The Ratimentioning

confidence: 57%

The Secular Trends in Male:Female Ratio at Birth in Postwar Industrialized Countries

Jongbloet¹,

Zielhuis²,

Groenewoud³

et al. 2001

Environmental Health Perspectives

View full text Add to dashboard Cite

“…The tendencies toward disproportionate attrition and loss of conceptuses at the very beginning and very end of the fertility window versus optimal survival at the middle of the window are in line with the "U"-shaped configuration in relation to the estimated ovulation date for conceptions that are destined to end in spontaneous abortion (29). In addition, these tendencies explain the other well-known "U"-shaped probabilities for delivering male offspring vis-à-vis timing of insemination in various animals or estimated ovulation in humans: insemination at the time of ovulation apparently biases the SSR in favor of equal sex proportions, in contrast to a moderate increase in males before or after ovulation (for pooled data, 94:100 vs. 117:100) (30).…”

mentioning

confidence: 55%

The secular trends in male:female ratio at birth in postwar industrialized countries.

Jongbloet

Zielhuis

Groenewoud

et al. 2001

Environ Health Perspect

View full text Add to dashboard Cite

Finnish investigators [Vartiainen et al. Environmental Chemicals and Changes in Sex Ratio: Analysis Over 250 Years in Finland. Environ Health Perspect 107:813-815 (1999)] presented the sex ratio of all newborn babies from 1751 to 1997 in order to evaluate whether Finnish long-term data are compatible with the hypothesis that the decrease in the ratio of male to female births after World War I and World War II in industrial countries is caused by environmental factors. They found an increase in the proportion of males from 1751 to 1920, which was interrupted by peaks in male births during World War I and World War II and followed by a decrease thereafter, similar to the trends in many other countries. The turning point of male proportion, however, preceded the period of industrialization and introduction of pesticides and hormonal drugs. Thus, a causal association between these environmental exposures and this decrease is unlikely. In addition, none of the various family parameters (e.g., paternal age, maternal age, age difference in parents, birth order) could explain the historical time trends. Vartiainen et al. concluded that at present it is unknown how these historical trends could be mediated. The postwar secular decline of the male:female ratio at birth is not an isolated phenomenon and parallels the decline of perinatal morbidity and mortality, congenital anomalies, and various constitutional diseases. This parallelism indicates a common etiology and may be caused by reduction of conceptopathology, as a correlate to increasing socioeconomic development. An inverted dose response or the dose-response fallacy due to vanishing male conceptuses explains the low sex ratios before World War I and World War II in newborns from black parents and from the lowest socioeconomic classes.

show abstract

“…It was only thereafter that the temperature elevation became significant reaching a peak of 37.1"C on the 27th day after a gradual rise. This pattern called "stepwise temperature rise" is well known to infertility workers and reproductive biologists (1,3,7). It is their general consensus that ovulation may occur almost at any point of the ascending slope and that the phenomenon belongs to the category of "luteal phase defect" (2); a recognized cause of intertility and reproductive abnormalities (6).…”

mentioning

confidence: 98%

Letter to the Editor

Iffy¹

1977

Acta Obstet Gynecol Scand

View full text Add to dashboard Cite

Aging of fertilizing gametes and spontaneous abortion

Cited by 23 publications

References 16 publications

The Secular Trends in Male:Female Ratio at Birth in Postwar Industrialized Countries

The Secular Trends in Male:Female Ratio at Birth in Postwar Industrialized Countries

The secular trends in male:female ratio at birth in postwar industrialized countries.

Letter to the Editor

Contact Info

Product

Resources

About