Reproductive Biomedicine

Publication Analysis 2007-2013
by Kathleen Gransalke, Labtimes 04/2015

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Image: Fotolia/ Hayati Kayhan

It’s a sensitive topic and affects almost everyone but, judging by its total citation counts, the heyday of reproductive medicine seems to be over. Our top 30 most-cited authors ranking is surprisingly dominated by Dutch researchers and short of female scientists.

Shortly before midnight, on July 25th, 1978, a British gynaecologist and a physiologist from Yorkshire had finally made one of mankind’s most daring dreams come true. On this day, Lesley Brown gave birth to her daughter, Louise Joy Brown, the first person conceived by in vitro fertilisation, IVF. Before that joyful day, Lesley and her husband, Gilbert Brown, had tried for many years to have children but because of Lesley’s blocked fallopian tubes, becoming pregnant was impossible.

The two doctors and scientists, who helped to usher in a new era in reproductive medicine, were, of course, Patrick Steptoe (father of two children, a son and a daughter) and Sir Robert Edwards (father of five daughters). “Without Patrick and Bob’s help, Mum wouldn’t have had me,” Louise Brown later said. At that time, not everyone was excited about this new technology. The Archbishop of St Andrews and Edinburgh, Cardinal Gordon Gray, expressed his concern, “I have grave misgivings about the possible implications and consequences for the future.” Well, despite the Catholic Church’s reservations, the future looked very bright for IVF. Millions of babies have since started their lives outside the human body, in a Petri dish. To top it off, in 2010, the Nobel committee honoured Edwards with the Nobel Prize in Physio­logy and Medicine.

This was 30 years ago. What’s the state of current reproductive biomedicine? Is England still spearheading this discipline? Judging from the nations’ ranking, the answer is yes. As previously mentioned, for this ranking, we only rely on so-called expert journals, as specified by the Web of Science database’s subject category, reproductive biology. Among the journals listed in that category is Human Reproduction, founded in 1986 by, you guessed it, Sir Robert Edwards.

With 41,626 citations, England clearly heads the nations’ performance table, followed by, no not Germany this time but Italy, with 35,288 citations. Germany comes in only in third place. Also, Turkey (11th) and Greece (13th) performed well, while research articles, reviews and proceedings papers from Swiss authors only collected enough citations for the 14th spot. Regarding average citations per article, two countries stand out: Denmark with 18.2 citations per article and Scotland (17.9).

Internationally, it’s the same pattern over and over again. European reproductive biomedical specialists wrote more articles (20,110 vs 12,098), garnering more citations (230,725 vs 155,586) compared to their US peers but, on average, a US article was cited more often (11.5 vs 12.9). The bronze place this time goes to Australia; China is only 6th. Hardly surprising, considering the fact that the Land of the Rising Sun has to deal with too many children, rather than too few.

Few citations for top papers

How about the most-cited papers and reviews of reproductive biomedicine published between 2007 and 2013? As was the case in our last publication analysis in parasitology, also here, total citations are rather low. The top paper gathered a mere 503 citations – a ridiculously small number compared to, for instance, the most-cited paper in Human Genetics (3,426 citations). Aren’t there anymore revolutionary discoveries to be made in reproductive biomedicine? Is it only about optimising existing technologies and improving diagnosis? Be it as it may, our top 5 papers all lean more or less towards the clinical side of reproductive medicine and not so much to the basic science side.

Hence, the top two papers are both about management of medical conditions, pre-eclampsia (hypertension and proteinuria during pregnancy) and polycystic ovary syndrome (a hormone imbalance disorder, resulting in poor fertility). Infertility prevalence is the topic of the third most-cited article and hormones (testosterone) are at the heart of paper number 4. Speaking about hormones, they turned out to be the crux of this publication analysis. Often, we found ourselves scratching our heads over the question, is he or she a true endocrinologist or a reproductive endocrinologist? The latter, of course, were suitable for our ranking, the former not.

So, let’s return to our question above, is England still the top dog in reproductive biomedicine? The nations’ ranking suggested yes; the most-cited authors ranking, however, paints a somewhat different picture. Only two scientists, affiliated with an English University or institute, made our top 30, which is, surprisingly, dominated by researchers working in the Netherlands. Not less than seven Dutch reproductive biomedical experts, including our number one, Eric Steegers (who also co-authored our most-cited paper), managed to secure a place in our top 30 authors ranking. Also surprising is the fact that male researchers so heavily dominate this discipline. Only one female reproductive specialist, Outi Hovatta (7th), managed to break that male dominance.

Let’s have a closer look at some of the most-cited scientists, specialising in reproductive biomedicine. Eric Steegers, our number one, is professor of obstetrics and prenatal medicine. He focusses on all things that can go wrong during pregnancy and what effects those things might have in later life. Also, Ben Mol (4th), who, last year swapped his Amsterdam office for a sunnier workplace at the University of Adelaide, is interested in pregnancy and child birth.

Successful reproduction, resulting in a pregnancy, implies, of course, sufficient reproductive capacities. Some of our top researchers, therefore, inspect disruptive factors of male fertility. Among these factors are hormone deficiencies (Maggi, nd; Forti, 3rd) or environmental toxins. Niels Skakkebaek (6th), for instance, found that “maternal beef consumption, and possibly xeno­biotics in beef, may alter a man’s testicular development in utero and adversely affect his reproductive capacity” (Hum Reprod, 22(6):1497-502). Male sexuality, including its disorders, such as erectile dysfunction and premature ejaculation, is the area of expertise for Giovanni Corona (11th) and Francois Giuliano (20th). In one of his papers, Corona found an interesting association between unfaithfulness in men and higher risk of major cardiovascular events (J Sex Med, 9(6):1508-18).

Deep frozen tissue – a hot topic

On the women’s side, increasing the success rate of IVF (Fauser, 5th; Devroey, 9th; Tarlatzis, 23rd and Andersen, 27th) and cryopreservation of ovarian tissue (Hovatta, 7th; Pellicer, 8th; Donnez, 15th) are the hottest topics. Jacques Donnez made quite a few headlines in 2012, when scientists questioned some of his studies. In one study, a woman, who was thought to be sterile because of chemotherapy, received an ovarian transplant from her sister and successfully gave birth to a child. Doubts were raised that the woman was really sterile before the transplantation. A second study “Livebirth after orthotopic transplantation of cryopreserved ovarian tissue” published by The Lancet in 2004, raised similar questions and four of the original co-authors withdrew their authorship to “ensure the integrity of the literature”.

Last but not least, some of our most-cited scientists study reproduction in mammals other than humans. Thomas D’Hooghe (26th), for instance, developed the baboon model for endometriosis research and Patrick Lonergan (19th) studies assisted reproduction in cattle and sheep.

“I think she was just very brave but I suppose if you’re told you can’t have children, you’ll do anything,” Louise Brown said about her mum. Indeed, the desire to have kids seems to be insatiable for some, bearing some bizarre fruit lately. Science has made the impossible possible – and enabled 65-year olds to become pregnant with quadruplets.

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Last Changed: 08.07.2015