Thank you for those of you who voted on which sessions I should attend today. You guys are so predictable. You voted on Aging and Male Reproductive Health and Safety of Assisted Reproductive Technology. I guess you’re not any more predictable than I am since these were the sessions I would have chosen as well.
Aging and Male Reproductive Health
Embryos do not show a gender differentiation until 6 weeks, but the beginnings of testicles are apparent (if you really know what you are looking for) at 8 weeks. At 3-6 months after birth, male babies go through a mini-puberty with rises in testosterone that equals mid puberty. The reasons for this mini-puberty are not clear, but they think it may have something to do with priming the brain for maleness. Testosterone drops of dramatically until puberty. Scientists do not know what sets of the pubertal clock (yes, that is an actual term), but there is strong evidence that the age of puberty is dropping, most likely caused by environmental factors. Unfortunately, they did not discuss what environmental factors were most suspect.
We all know that it possible for a man to father children into old age (the oldest man to do so was 94), but it is surprisingly hard to study from an epidemiological standpoint if male fertility declines with age, since the male factor is masked by the decline in female fertility with age. To study the effect of age on male fertility a population is needed where:
- Contraceptives are not routinely used
- High quality records are kept
- Greater acceptance of older men married to younger women
The Mormons have historically provided such a population, and studies of this population have found that male fertility declines only slightly with age, and doesn’t begin men are older than 70.
The presentation, however, supported the findings that there are genetic hazards with older fathers. Miscarriages are more common with older fathers. Psychiatric problems are higher in the offspring of older father, such as bipolar, schizophrenia, and autism. The presenters went into little new details on the increased prevalence of these mental illnesses since this was not the subject off their research and they were simply summarizing the existing research on this topic.
Safety in Assisted Reproductive Technology
The session on Safety in Infertility Treatment was disappointing since most of the presentation focused on safety risk for women with Turner syndrome. Bottom line: assisted reproductive technology should only be used with extreme caution for women with Turner syndrome. I was more interested in the very short part of the presentation on the health risks for children conceived through ICSI. They basically summarized the recent research which has found that 118 children born after ICSI and studies at age 14 had a increased fat accumulation and different fat distribution than a control group of children conceived naturally. In all other respects, the ICSI group was comparable to the control group.
Other health/safety news from the conference is that overweight women undertaking fertility treatment are twice as likely to miscarry as women with normal Body/Mass Indexes.Image credit: marcus_and_sue