Reproductive Aging

When a member of the Nature family of journals publishes a collected issue of reviews, it is a signal of significance. Nature Aging recently published “Reproductive Aging” with open access. It covers hot topics in clinical and animal research in five review articles and several commentaries, mostly, though not exclusively, on female biology and medicine.

Reproductive aging is not just about reproduction: its relevance to health extends to immunology, pathology, and obviously the postmenopause and premature male hypogonadism. The ongoing controversy over estrogen replacement therapy is discussed along with a new remedy for vasomotor symptoms. There are many candidates for reversing aging, ranging from nutritional supplements to stem cells, including rapamycin or metformin, and even in vitro gametogenesis (topic coming here soon). Theoretical ways of combating aneuploidy in oocytes and extending the ovarian lifespan get due attention, plus a reappraisal of the ovarian stroma, long regarded as merely organ “bulk.”

I chose reproductive aging from my advisor’s short list for graduate research. Looking back on that decision decades later, it seemed an eccentric choice in the literal meaning of the word for an offbeat territory compared to mainstream topics my peers worked on - capacitation for fertilization, tracing embryonic lineages, testicular immunology, and so on. The field looked fallow with sparse cultivation in journals and some weeds of disreputable work in its history. But I was glad to be free of competitors, even if my endeavors had little prospect of being noticed or clinically relevant.

Among the few people engaged in the 1970s, I read papers and corresponded with Drs. Blaha, Butcher, Foote, Meites (USA), Aschheim (France), Peng & Huang (S. Korea), Adams and Finn (UK). Solly Zuckerman’s group in Birmingham did sterling work two decades earlier, proving the population of ovarian follicles is fixed at birth (a challenge in the 2000s was quashed). Otherwise, the subject was the domain of clinical practitioners or the pharmaceutical industry’s focus on hormones.

How times change! American women have delayed their first childbirth from 21 years old fifty years ago to an average 28 today, while rising to the thirties in Western Europe and island nations in East Asia. Hence, there are at least two explanations for why reproductive aging research now wins more support from grant funding agencies and top journals. For one, Millennials and Generation Z gamble with the declining odds of beating the infertility trap in the years running up to the menopause, and for another, the role of reproductive endocrinology in somatic aging is clear.

Aging is no longer a dead-end for young graduates looking for a subject to keep them absorbed in science over a long career.

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