The impact of male age on fecundity remains controversial. Here, a large population study was used to investigate the effect of paternal age on time to conception. All couples in the Avon Health district expecting a baby between 1 April 1991 and 31 December 1992 were eligible. Questionnaires completed by both the man and the woman at 18 weeks gestation covered specific fertility factors, e.g. parity, paternity, cohabitation and oral contraception; and non-specific factors, e.g. educational achievement, housing, cigarette smoking, alcohol consumption, obesity. Logistic regression was used to identify factors independently related to conception in ≤6 or ≤12 months. Of 8515 planned pregnancies, 74% were conceived in ≤6 months, 14% in the second 6 months and 12% after more than a year. Nine variables, including the age of the woman, were independently related to time to conception. After adjustment for these, the likelihood of conception within 6 or 12 months was lower in older men. Compared to men <25 years old, the adjusted odds ratios (95% confidence interval) for conception in ≤12 months were 0.62 (0.40, 0.98), 0.50 (0.31, 0.81) and 0.51 (0.31, 0.86) in men aged 30–34, 35–39 and ≥40 years respectively.
That might explain Harry. And the kale smoothie diet. Good for sperm.
When people wait too long on purpose, with the right person, and find out they can’t have kids any more, I like to think it’s Mother Nature flipping them off with one hand and punching them in the balls with the other.
Why, you ask?
“the overall association with age was highly statistically significant. If the man’s age was treated as a continuous variable there was a significant linear relationship: the odds ratio for conception in ≤6 months decreased by 2% per year of age (P < 0.01) and for conception in ≤12 months by 3% (P < 0.001).”
Every year a man goes over 25, his likelihood of easy conception drops by 2%.
“These results suggest that there is a larger decline in male fecundity with advancing age than reported in earlier population studies (see above).”
That is all pretty funny considering the guys who think they have Thor-immortal sperm.
More like thaw.
“Therefore our conclusions would remain valid even if the most fertile of the older men had been eliminated from the study group because they achieved unplanned pregnancies. If the opposite bias predominated and the less fertile couples were lost from the older groups, we would underestimate the effect of age on male fecundity. It is unlikely that a substantial number of men aged ≤24 years would believe themselves to be sub-fertile….
Please call it virility. Men don’t give birth, they can’t be fecund. Just call the impotence, impotence. There are levels.
Were this true of older men, it would again lead to an underestimate of the effect of age on fecundity.”
“…However, they do not exclude the possibility that the greater fecundity of young relative to older men was more marked in the past.
….It is also possible that more fertile men complete their families sooner, and less often try to father children in their thirties or forties.”
It gets worse. You can’t supplement your way out of ball shrinkage.
Although most data come from elderly men changes can be detected in middle age (Erfurth and Hagmar, 1995; Bonavera et al., 1997). There are a number of morphological changes in the ageing testis, including a decrease in the number of Leydig cells (Neaves et al., 1985), a decline in Sertoli cell numbers and daily sperm production (Johnson et al., 1984a,b) and an increase in the involution of seminiferous tubules (Paniagua et al., 1987). Spermatozoa from older men are less fertile after intrauterine insemination (Mathieu et al., 1995; Brzechffa and Buyalos, 1997) or in donor insemination (Lansac, 1995). These observations support the conclusion that the effects of paternal age on a couple’s fecundity are real and may be greater than previously believed. After adjustment for other factors, the probability that an ultimately fertile couple will take >12 months to conceive nearly doubles from ~8% when the man is <25 years to ~15% when he is >35 years and paternal age is a further factor to take into account when deciding the prognosis for infertile couples.
Doubles in ten years. That’s worse than any female stat. It tanks!
What about the sperm?
Reduced fertility typically occurs among women in their late 30s, but increasing evidence indicates that advanced paternal age is associated with changes in reproduction as well. Numerous studies have investigated age-based declines in semen traits, but the impact of paternal age on semen parameter values remains inconclusive.
Clear rationale, nice.
Using data from 90 studies (93,839 subjects), we conducted a systematic review and meta-analysis to quantify the effect of male age on seven ejaculate traits (semen volume, sperm concentration, total sperm count, morphology, total motility, progressive motility and DNA fragmentation). Age-associated declines in semen volume, percentage motility, progressive motility, normal morphology and unfragmented cells were statistically significant and results generally seemed to be robust against confounding factors. Unexpectedly, sperm concentration did not decline with increasing male age, even though we found that sperm concentration declined over time.
More chance of mutant sperm, future psychiatrist patient babies! Lucky you!
It would be better if they made less but retained quality than risk stillbirth.
Our findings indicate that male age needs more recognition as a potential contributor to the negative pregnancy outcomes and reduced offspring health associated with delayed first reproduction. We suggest that greater focus on collection of DNA fragmentation and progressive motility in a clinical setting may lead to better patient outcomes during fertility treatments of aging couples.
Ouch. Thirties is now aging? Well, I guess in medicine, it is.
Really, 40 is the age where male fertility tanks severely.
Like, you’d be better off not conceiving than risk the cost of a disabled kid.
Result(s): The odds ratio of failure to conceive for paternal age 40 years was 2.00 (95% confidence interval [CI]: 1.10–3.61) when the woman was 35–37 years old, 2.03 (95% CI: 1.12–3.68) for age 38–40 years, and 5.74 (95% CI: 2.16, 15.23) for age 41 years and over.
Conclusion(s): As an increasing number of couples choose to postpone childbearing, they should be informed that paternal age over 40 years is an important risk factor for failure to conceive.
This marked maternal age effect led to the conclusion that 35 years is the “amber light” in the reproductive life of women (4).
Paternal age was long almost ignored in studies of age effect on reproductive outcomes, but its potential role has recently been investigated. Some works have shown that increasing paternal age is accompanied by greater risk of delay in achieving pregnancy, of miscarriage and of late fetal death (5–8). In a recent review of the literature, we considered that 40 years could be the “amber light” in male reproductive life, as is 35 years for women’s reproductive life (9)
Wow, five years. Almost the average difference of successful marital unions. (Wait, exactly that, the man is five years older). Now I know why it’s Mother Nature.
…. To analyze paternal age effect mediated by biological aging alone, data on medically assisted cycles provide a very interesting model
Our results provide, for the first time, strong evidence for a paternal age effect on failure to conceive that is linked only to biological male aging (without confusion with sexual activity). We observed a clear tendency to increased risk of failure to conceive, especially when the fathers were over 40 years old. Results in the first and last classes in Table 2 (older woman with young man or young woman with older man) should be interpreted with caution because of the small number of couples in these classes. We thus analyzed Table 2 by concentrating on classes with at least 30 couples. This revealed a clear increase in risk of failure to conceive with paternal age.
Our results on a paternal age effect after 40 years are in accordance with results recently published concerning the general population. In a European population-based study of
couples attempting to conceive naturally, a significant odds ratio of 2.99 (95% CI: 2.77, 7.55) for the risk of not having conceived after 12 months of attempting to achieve pregnancy was observed when the woman was 35–39 years old and the man 40 years old and over (7). A similar tendency was observed in another European study of 782 couples, which showed a decrease in the daily probability of conception in couples composed of a woman 35–39 years old and of a man in his late thirties or older (8).
It has been demonstrated that couples having difficulty in conceiving also have an increased risk of miscarriage (19).
Thus, the association between paternal age and failure to conceive raised the question of a possible association between paternal age and miscarriage. In the literature, an
increased risk of miscarriage was observed in couples composed of a woman 35 years old and over and of a man 40 years old and over (OR 6.73; 95% CI: 3.50, 12.95) (6).
What about 50+? Obvious grandfather territory.
More recently, in a large Danish cohort, a twofold increase of the risk of early fetal death was found when the father was 50 years old and over compared with fathers 25–29 years
old, after controlling for various confounders and especially for maternal age (5). In the same cohort, the authors showed a paternal age effect as early as 45 years when considering late fetal deaths.
Yet they’ll still try to blame it on the women….
….The authors concluded that elevated paternal age (35 years) increased the risk of spontaneous abortion during the first trimester and at the beginning of the second trimester, with a suggestion that the association was stronger for deaths occurring during the first trimester.
large genetic abnormalities
Interestingly, a remarkable concordance exists among all these studies, stressing the fact that older fathers (40–45 years old) have a key impact on both reproductive issues, failure to conceive, and miscarriage.
When a man conceives, his sperm quality is all he contributes. Male age will be a much larger factor than anything female, all things considered. Try making a decent omelette with stale eggs. Try fertilizing an ovum with old sperm. The single ingredient on that side of equation becomes very. very important.
Women in that case are trying to compensate for the errors of men.
The mechanism for the paternal age effect remains to be explained.
Aging germline DNA is not better DNA.
Previously, as for maternal age, the genetic hypothesis had been emphasized (21, 22). After analysis of 11,535 pregnancies obtained by artificial insemination using donor spermatozoa, an increased risk of trisomy 21 for the fetus when the donor was 38 years old has been suggested (23).
A lot of my generation thinking they can wait will be sorely mistaken.
Gambling your future, literally.
In reproduction, age must no longer be considered as the concern of the woman, but as that of the couple. Similar to maternal age over 35 years, paternal age over 40 years is a key risk factor in reproduction.
The results showed that maternal age was closely linked to decreased pregnancy rate, which was 8.9 per cent in women over 35 compared to 14.5 per cent in younger women.
But the scientists also found that the father’s age was also important, not only on pregnancy rates, but perhaps more surprisingly, on the rate of miscarriage, with a pronounced negative effect once the father was over 35 years of age…
A representative of the Eylau Centre also said on an interview with the BBC aired early this morning that the likely cause of the decrease in male fertility after 35 was DNA fragmentation. He said that DNA fragmentation was not unusual in male sperm and often this is repaired “by the woman”, but when it is too fragmented it is beyond repair, leading to pregnancy failure and miscarriage, he said.
They’ll still blame the woman.
There’s a reason all of Henry VIII’s kids died childless.
Frozen sperm is only good for about ten years, by the way.
Maybe instead of proving their manliness by submitting to 23andMe, these guys should be getting their sperm quality checked and post those results.
Sperm donors have an age limit of 40.