Credits: Maggiejumps / Wikimedia Commons — CC BY 2.0.
At the Royal Albert Hall in London, United Kingdom, on December 1, 2025, Sienna Miller, 43, revealed on the red carpet at the Fashion Awards 2025 that she is pregnant with her third child, wearing a sheer white Givenchy dress that felt like a manifesto. Alongside Oli Green, the actress turns a celebrity pregnancy into a societal topic: motherhood after 40, age norms and representation. What do the numbers and doctors say about this growing delay?
On The Red Carpet, A Controlled Staging
December 1, 2025, Royal Albert Hall in London. At the Fashion Awards 2025, Sienna Miller appeared in a sheer white Givenchy dress (SS 2026, creative direction: Sarah Burton). Empire waist, airy tulle, visible white undergarments: the actress presented a clearly visible Sienna Miller baby bump to the cameras. No statement was released: the image spoke for itself. Arm in arm with Oli Green (28), Miller’s partner, she thus sealed, on a red carpet that has become a media in its own right, the announcement of her third pregnancy — her second child with her partner.
With her boho-chic look (wavy hair, restrained makeup, dangling earrings), the British star claims a sartorial language she has mastered since her beginnings: transparency not as provocation, but as self-assertion. This aesthetic, much discussed in the fashion press, feeds another trend: the rise of the naked dress and naked dresses as well as proudly displayed pregnancy looks on the red carpet.
A Personal And Stylistic Trajectory
Discovered in film and on stage, Sienna Miller (43) is already the mother of Marlowe (born in 2012 from her relationship with Tom Sturridge). With Oli Green, whom she met in 2022, she welcomed a baby girl in late 2023 / early 2024 (the couple did not disclose a precise date or name). The new pregnancy fits into an intimate timeline the actress has sometimes discussed. She feels the pressure of the biological clock after 40. She also decided to freeze eggs. Moreover, she wants to defy age injunctions that weigh on women.
Stylistically, the London moment answers a striking precedent: at Vogue World: London in September 2023, Miller already showcased her pregnant belly in a spectacular look. This dialogue between fashion and motherhood draws a common thread: making visibility a lever of personal narrative, sometimes subversive.
Pregnancy After 40: What The Numbers Say
Beyond the glamour of the Fashion Awards 2025, Miller’s trajectory echoes a well-documented demographic shift. In France, the average age at childbirth continues to rise and reached 31.2 years in 2024 (provisional). The average age at first birth was 29.1 years in 2023, confirming the postponement of motherhood. At the European Union level, the average age at first birth was 29.8 years in 2023. However, there are significant disparities between countries.
In this context, motherhood after 40 is no longer marginal. In 2019, 5.7% of births in France were to mothers aged 40 or over. Recent obstetric research shows a continuous increase in this share, around 5% to 6% in the early 2020s. An estimate of 6.5% in 2022 is cited in the medical literature.
This dynamic is not only a matter of individual choice; it is driven by structural factors: longer education, precarious career starts, housing costs, relationship instability, and access to fertility preservation techniques (such as egg freezing). It also takes place within a general decline in birth rates in Europe. Nevertheless, France remains one of the more fertile countries.
What Medicine Reminds Us: Risks And Monitoring
Specialists note that pregnancies beyond 40 are more common than thirty years ago. Moreover, these pregnancies are now better monitored. However, they remain statistically higher risk. Without dramatizing, it is important to recall the increased risks: gestational diabetes, pregnancy hypertension / pre-eclampsia, growth restriction, prematurity, and a higher likelihood of cesarean delivery. Information should remain general, without extrapolating to any given individual’s case. Professional and institutional reference sources detail these elements. They emphasize the importance of appropriate obstetric follow-up. They also stress the relevance of metabolic monitoring. Furthermore, they recommend personalized care.
In public debate, a balance is required: do not over-medicalize successful late motherhood journeys, while reminding that obstetric risk increases with age. Health actors encourage clear information, preconception consultations when the child project is considered late, and closer monitoring during pregnancy.
Representations And Realities: The Celebrity Lens
Sienna Miller’s visibility adds to other publicized trajectories — Virginie Efira (46, gave birth in August 2023), Janet Jackson (50 in 2017). These stories create a positive imaginary around late motherhood: affirmation of the body, control of the timeline, freedom to decide. But they also reflect privileges: access to expert medical teams, reproductive technologies, time and resources that not all women can marshal.
Hence the need, for a general news outlet (IPG), to distinguish what inspires from the everyday reality experienced by the majority. Yes, the age norm is shifting; no, the social reality does not erase inequalities in access to care, prevention, parental leave, or egg freezing (very expensive outside medical indications in several countries).
Fashion, Body, Society: What A Sheer Dress Changes
On stage, Miller rewrites the vocabulary of the maternity dress: here, no wrap or strategic volume, but a transparency that assumes and proclaims. The sheer white Givenchy dress — by Sarah Burton, whose arrival as creative director reoriented the house’s aesthetic — evokes both femininity and a contemporary gaze on motherhood.
Does this gesture influence fashion? In the short term, it accelerates trends already present: naked dresses, visible undergarments, light colors, empire silhouettes. In the medium term, it contributes to a movement where motherhood becomes representable differently: neither sacralized nor hidden. The question remains: does this symbolic reconfiguration benefit the many? It can help normalize pregnancy at work or in public spaces; it does not replace social policies (parental support, reproductive health, combating age and gender bias).
Box: Key Figures To Remember
- 31.2 years: average age at childbirth in France in 2024 (provisional).
- 29.1 years: average age of mothers at first birth in 2023 (France).
- 29.8 years: average age at first birth in the EU in 2023.
- 5.7% of births in 2019 in France were to mothers aged 40 or over (around 5–6% since).
Timeline
- 2012: birth of Marlowe, Sienna Miller and Tom Sturridge’s eldest daughter.
- 2022: start of the Sienna Miller / Oli Green relationship.
- Late 2023 / early 2024: birth of the couple’s first daughter (name not disclosed).
- December 1, 2025: Fashion Awards 2025 at the Royal Albert Hall in London; Sienna Miller reveals her third pregnancy in a sheer white Givenchy dress (SS 2026).
Beyond Celebrity: A Societal Debate
Sienna Miller’s appearance in London is not celebrity fluff. She stages a life moment and, in doing so, highlights a weighty trend: later motherhood in European societies. She invites discussion of fashion, body, representation, but also public policy. Celebrity does not exhaust the issue; it makes it visible: at 43, under a sheer dress, a famous woman poses, without a word, the terms of a debate that the IPG must continue to document.