Fertility
Study reveals how assisted reproduction affects placenta and child’s growth

Approximately one in six couples trying to have a child experiences infertility. Each year, over five percent of children in Finland are born with the help of Assisted Reproductive Technology (ART), and to date, over ten million children worldwide have been conceived using these techniques.
Although ART-conceived children are generally healthy, a slightly increased risk of growth disturbances as well as cardiovascular, metabolic, and neurodevelopmental disorders has been observed. The underlying causes of the risks, and whether they result from the ART procedures or parental subfertility, are unknown.
To understand the molecular mechanisms behind ART-associated risks, researchers have examined newborns and placentas from 80 ART and 77 spontaneous pregnancies. When the placentas were compared, they considered different ART methods as well as the children´s sex for the first time.
The placenta has proven to be an extremely fascinating organ which connects the mother and the foetus, mediates environmental effects on the foetus and influences foetal development.
“The placenta offers a unique window into the very early developmental stages, which are otherwise difficult to study in human”, says associate professor Nina Kaminen-Ahola, the leader of the study in the University of Helsinki.
Frozen embryo transfer resembles natural pregnancy
Genome-wide placental gene function and DNA methylation, the most well-known epigenetic mark involved in gene regulation, were examined. Also, potential connections between the observed changes and the placental weight as well as newborns’ weight and height were studied.
One of the most interesting findings concerned the two commonly used ART methods, fresh and frozen embryo transfer. In the fresh embryo transfer, the IVF-fertilised embryo is transferred directly from the culture dish into the uterus, while in the frozen embryo transfer the embryo is frozen for a varying period before the transfer.
Several studies have discovered that placentas and children from fresh embryo transfer are smaller on average compared to those from frozen embryo transfer. This was also the case in the current study. Particularly, it was seen that the observed changes related to metabolism and growth were specific only to placentas from fresh embryo transfers.
“Almost all placentas from frozen embryo transfers had been transferred into the uterus during the mother’s natural cycle, rather than during an artificial hormone surge as in the case with fresh embryo transfers. Consequently, the onset of pregnancy in these cases resemble more spontaneous pregnancies,” explains Pauliina Auvinen, the doctoral researcher on the project.
Altered gene is linked to obesity and diabetes
In addition, the researchers identified altered function of a gene called DLK1. The expression of this gene was reduced in both ART placentas and in placentas from pregnancies of subfertile couples who had applied for fertilization treatment but who got pregnant spontaneously.
The DLK1 gene regulates metabolism and has been associated previously with obesity and type 2 diabetes. Additionally, it can have a role in maternal physiological adaptations to pregnancy.
According to a previous mouse study, Dlk1 is essential for proper maternal fasting response during pregnancy, enabling the switch to using fat for energy resource and thereby securing foetal growth. Silencing of Dlk1 was also associated with the offspring’s lower birth weight.
Kaminen-Ahola says that the silencing of DLK1 gene has also been linked to low birth weight in humans.
“The role of this gene in subfertility and the increasing metabolic disorders such as obesity and type 2 diabetes,” needs to be further clarified.
More research needed
Despite the significant new results, more samples need to be collected to better understand the effects of the different fertility treatment methods, subfertility, and sex on the children´s development and health. In addition, understanding the long-term impact of ART requires long-term monitoring of the children.
“Based on the results, it will be possible to improve ART treatments and understand the causes of sub- and infertility. We are continuously collecting more samples, and we warmly thank all the families for participating in the epiART study,” said Kaminen-Ahola.
Entrepreneur
Applications open for the third W Accelerate with Merck KGaA and M Ventures

W Group has opened applications for W Accelerate with Merck KGaA and M Ventures, inviting reproductive and maternal health startups, scaleups and spinouts to pitch for direct access to global pharma partnership and strategic investment.
Selected companies will pitch on 5th October, competing for the chance to accelerate their growth through commercial partnerships, investment, or both.
This is the third time Merck KGaA, a global leader in reproductive health, has partnered with W Group on the programme, which exists to close the innovation and investment gap in women’s health by connecting the sector’s most promising startups directly with the corporates and investors positioned to scale them.
What Merck KGaA and M Ventures are looking for
This year’s call is focused on breakthrough solutions in female infertility, fertility preservation, adenomyosis, endometriosis, polyendocrine metabolic ovarian syndrome (PMOS), ovarian insufficiency, preeclampsia and pregnancy comorbidities.
New for this round, applicants choose between three pathways depending on what they need from the programme:
- The Partnership Lane, for companies seeking commercial collaborations and strategic relationships
- The Investment Lane, for founders looking to connect with investors and secure funding to scale
- The Dual Lane, for innovators pursuing both partnership and investment opportunities
How the Accelerate event works
Selected companies get a 1:1 pitch practice session ahead of time, then a private 30-minute session with Merck KGaA and M Ventures leadership on the day itself, small-group sessions with regulatory and investment strategy experts, an “Ask Merck Anything” roundtable, and a VIP networking reception.
Key dates
- Open call launches: 8th July
- Open call closes: 2nd September
- Notification of successful companies: 11th September
- Pitch day: 5th October
Applications are open now at wplatform.typeform.com/to/KGzviBQM.
Fertility
Older women face lower chance of fertility treatment working, even with donor eggs, study finds

IVF success declines with age even when women use young donor eggs, with a marked fall from around 49, research suggests.
The findings challenge the idea that donor eggs can fully “reset” the reproductive clock, although researchers said they should not discourage older couples from trying.
Dr Beatrice Crestani, from an assisted reproduction medical institute in Italy, said reproductive ageing had traditionally been seen mainly as an issue involving the ovaries.
She said replacing older eggs with younger donor eggs was often believed to “reset” the reproductive clock.
Dr Crestani added: “Our findings suggest the picture is more complex.”
The study followed 1,774 women undergoing in vitro fertilisation, or IVF, using donated eggs. IVF involves fertilising an egg in a laboratory before transferring an embryo to the womb.
Women in their mid to late 30s had a 54 per cent chance of becoming pregnant after treatment, compared with around 43 per cent among those aged 49 or older.
Live birth rates fell from 46 per cent to 32 per cent, while miscarriage rates rose from 24 per cent to 38 per cent.
Women aged 49 and older had twice the risk of miscarriage compared with those aged 35 to 40.
Researchers believe changes to the endometrium with age may help explain the difference. The endometrium is the lining of the womb where a fertilised egg or embryo implants and grows.
Although the thickness of the womb lining was similar across the age groups, its condition declined with age.
Researchers said future work might find ways to predict, prevent or improve uterine ageing.
Dr Crestani said: “These findings should not discourage women from pursuing donor-egg treatment, because success rates remain meaningful even at advanced ages.
“However, patients should be counselled that donor eggs cannot completely eliminate the effects of reproductive ageing, particularly beyond 49 years.”
Among women who transferred all their available embryos, the live birth rate was around 80 per cent for those aged 35 to 40 and 62.5 per cent for those aged 49 or older.
Experts stressed that the health of the womb and ovaries differs between women.
There is no legal upper age limit for IVF in the UK, unlike some European countries. Greece has an upper limit of 54.
Women in the UK can donate or share their eggs up to the age of 36.
Regulators ask private UK clinics to assess the welfare of any resulting child and whether the recipient can safely carry a pregnancy.
NHS guidelines recommend offering three IVF cycles to women up to the age of 40 and one cycle to women up to the age of 42.
Patients using donor eggs usually have to fund that part of the treatment themselves.
People conceived using sperm, eggs or embryos from donors registered after 1 April 2005 can request identifying information about their biological donor parent once they turn 18.
The findings are being presented at the European Society of Human Reproduction and Embryology.
Professor Borut Kovacic, chair-elect of the society, said researchers were trying to better understand the “cross-talk” between an implanting embryo and the womb lining. This refers to the biological signals exchanged during implantation.
He said the age threshold associated with the beginning of a loss of uterine function was unlikely to be absolute.
Professor Kovacic added: “It provides important information for patients and offers a valuable foundation for future research aimed at identifying novel biomarkers of uterine ageing.”
Dr Ippokratis Sarris, chair-elect of the British Fertility Society, called for more research.
He said pregnancies could carry greater risks for older women and recommended thorough health checks and counselling for couples beginning fertility treatment.
Insight
Women with PMOS should have annual NHS checks, new guidance says

Women with PMOS should receive annual NHS checks to spot related health risks sooner, according to new draft guidance.
Polyendocrine metabolic ovarian syndrome (PMOS) is a complex condition that can have wide-ranging effects across the body.
It affects around one in eight women and was formerly known as polycystic ovary syndrome. It was renamed in May to better reflect its broader effects.
Draft guidance from the National Institute for Health and Care Excellence (NICE) calls for quicker diagnosis and better monitoring.
Marie Anne Ledingham, consultant clinical adviser for women’s and reproductive health at NICE, described the recommendation for a “simple” annual review as an “important step”.
She said: “This new guideline will help improve consistency of care, increase awareness of the condition, and support earlier diagnosis and management.”
PMOS is a major cause of female infertility. Symptoms can include irregular or absent periods, difficulty becoming pregnant, excessive facial or body hair, weight gain, hair loss, oily skin and acne.
An estimated three million to four million women have the condition in the UK, but NICE says it remains underdiagnosed and inconsistently managed.
The proposed annual reviews would cover current symptoms and longer-term health risks linked to the condition, including diabetes and heart disease.
NICE says lifestyle changes and treatment could help prevent more serious illness.
There is no cure for PMOS, but NHS treatments can help manage its symptoms. These include hormone support and fertility drugs.
The draft guideline does not recommend laser or light therapies for hair reduction because of the cost.
Many women report difficulty understanding the possible cause of their symptoms or experience delays before receiving a diagnosis.
When doctors suspect PMOS, they may use blood tests to assess hormone levels and ultrasound scans to look for the multiple follicles often seen on the ovaries of those affected. Follicles are small, fluid-filled sacs in which eggs develop.
The draft guideline sets out when healthcare professionals should suspect the condition and how women should be assessed and diagnosed.
It also says PMOS should not be ruled out in women who have been through the menopause.
The condition is thought to be more common among black, Asian and mixed-ethnicity women. NICE says healthcare professionals should consider this when assessing symptoms.
PMOS can also have a significant effect on mental health and quality of life, with depression and anxiety described as common among women with the condition.
Women planning a pregnancy should receive advice on weight, diet, nutrition, exercise, sleep and mental health, according to the guidance.
The draft guideline is open for consultation from 1 July to 11 August 2026, with feedback invited from healthcare professionals, patients and the public.
The final guideline is expected to be published in December 2026.
Cancer2 days agoThousands of women could avoid painful cancer exam with new AI blood test
Insight4 days agoWomen with PMOS should have annual NHS checks, new guidance says
Diagnosis3 days agoTwo “gamechanger” tests set to speed up endometriosis diagnosis on the NHS
Entrepreneur1 week agoKorea’s Femtech Industry Goes Global as Vespexx Hosts Korea Femtech Summit 2026
Fertility2 weeks agoImmunotherapy may temporarily restore fertility in premature menopause
News1 week agoBreast cancer biosensor and low-cost ultrasound startups win women’s health AI competition
News2 weeks agoDon’t miss HTW’s upcoming deep dive into health AI
News1 week agoClue spotlights seven women’s health journeys in new campaign








