Singapore Zoo welcomes first Sumatran orangutan born via caesarean section after assisted reproduction

• Birth of male baby orangutan, Ayaan, follows years-long effort to preserve a genetic line that would otherwise have been lost
• Procedure believed to be the first documented case globally involving placenta praevia in an orangutan where both mother and infant survived
• Chomel and Ayaan have been introduced to the orangutan exhibit, where guests may catch a glimpse of the pair

Dr Cheng Wen-Haur, Deputy CEO of Life Sciences and Chief Life Sciences Officer, said, “Ayaan’s birth is the result of years of careful planning and teamwork behind the scenes. Faced with a complex and high-risk pregnancy, our teams brought together all available expertise to give both mother and infant the best possible chance.  This reflects the value of science-led, collaborative breeding programmes in safeguarding critically endangered species for the long term. During the same period, we also welcomed the natural births of two Bornean orangutans. Together, these births show the range of care we provide. Most of the time, we let nature take its course, and when needed, we step in to lend a helping hand. That ability comes from decades of experience and deep understanding built through decades of caring for these animals.”

Ayaan is the first offspring of Charlie, a 48-year-old Sumatran orangutan whose genetic profile is unrepresented in the managed population of the species. The pairing of Charlie and Chomel was recommended under the Southeast Asian Zoos and Aquariums Association (SEAZA) Species Management Programme for the Sumatran orangutan, a regional cooperative breeding programme co-coordinated by Mandai Wildlife Group. Despite multiple attempts at pairing since 2018, none have resulted in a successful conception, and the team turned to assisted reproductive methods.

Wendy Chua, Curator, Animal Data Management & Transactions and Primates, and SEAZA Species Co-Coordinator for orangutan, said, “From the beginning, the goal was to give Charlie’s genetic line the best chance of continuing. Without a successful breeding, his line would have been lost. The programme considers many factors, genetics, temperament and maternal history, and Chomel was a strong fit in every regard. I was part of the baby team, monitoring Ayaan right after delivery, including his respiratory rate, his reflexes, and his colour. It was the longest seven minutes I have ever experienced. Seeing both of them doing well today, especially Chomel, there is no better outcome."

As part of their daily care routine, the animal care team had conditioned Chomel over the years to voluntarily take part in ultrasounds, blood draws, and health checks. That foundation of trust, built long before this pregnancy, proved critical to what followed. It enabled detailed hormone profiling from September 2021 to April 2023 to better understand Chomel’s reproductive cycles, allowing for a more targeted approach to reproductive management. Three artificial insemination attempts followed in May 2022, March 2023 and July 2025. The third was successful.

The pregnancy progressed well until January 2026, when Chomel experienced two episodes of notable vaginal bleeding. The diagnosis was placenta praevia, a condition where the placenta sits over the birth canal, creating a high risk of severe bleeding and potentially preventing natural delivery. The animal care team monitored Chomel around the clock, while ultrasounds confirmed the infant's heartbeat remained stable. Informed by her previous gestation period, the team identified March as the best time to perform a planned caesarean section, ensuring Ayaan would be born as close to term as possible.

The veterinary and animal care teams had two months to prepare for what would be a rare surgery and a first for the institution. Preparation included extensive planning and the engagement of external medical and surgical expertise to support the procedure. Given the risk of haemorrhage, the team also identified a compatible blood donor ahead of surgery. Chomel's cousin and foster daughter, also named Ah Meng, was a blood match. Her blood was collected for use during the operation.

233 days into her pregnancy on 18 March 2026, Mandai Wildlife Group’s veterinary team were joined by an external veterinary surgical specialist, with human obstetric and neonatal specialists providing real-time consultation throughout – a reflection of the complexity of the case and the close parallels between human and orangutan anatomy. After 20 minutes, Ayaan was delivered successfully and transferred immediately to a separate room. While breathing, he presented with low oxygen and heart rate and was cold to the touch at the beginning. For seven minutes, the team worked to stabilise him. Once his condition improved, he was placed in an incubator as Chomel recovered from anaesthesia.

Dr Heng Yirui, Deputy Vice President, Veterinary Healthcare & Scientific Programmes, Mandai Wildlife Group, said, “Chomel’s calm, trusting nature and cooperation with routine health examinations allowed us to monitor her closely throughout her pregnancy. When the complication arose, we carefully evaluated every option and determined that a caesarean section was the only way to give both mother and infant the best chance of survival. Seeing her immediately embrace Ayaan when she woke from surgery was an incredibly relieving moment, and it reassured us that we had made the right decision. To our knowledge, this is the first documented case of an orangutan birth spanning artificial insemination, placenta praevia and a successful caesarean delivery. We hope sharing this experience will contribute to advancing veterinary knowledge and the care of great apes worldwide.”

Caesarean sections in orangutans are exceptionally rare, with only around a dozen recorded cases in the United States over the past two decades. Placenta praevia is also rarely recorded in orangutans under human care, making this case particularly significant to the global body of veterinary knowledge.

Chomel took to motherhood with characteristic grace, nursing Ayaan within 24 hours of the procedure. As she regained her strength in the weeks that followed, she quietly took on more, as the animal care team closely monitored her. March and April also saw the natural births of two Bornean orangutans at Singapore Zoo, born to Miri and Niu Li, respectively. Niu Li, a first-time mother, gave birth on 11 April. While attentive to her newborn, Lio, she experienced difficulties nursing. Knowing Chomel's temperament and her history of caring for infants not her own, the animal care team made the decision to place Lio with her to ensure the baby received adequate nursing care to support its healthy development. Chomel accepted the male baby without hesitation and is now nursing both infants.

To give Chomel the space she needs as a nursing mother, the Sumatran orangutans will be on a rotational schedule. Chomel and the babies, Ah Meng and Niu Li, will be in the exhibit from Thursday to Sunday and public holidays, while the two males, Charlie and Riau, can be seen from Monday to Wednesday. As Chomel tends to her infants, she may at times choose to retreat to quieter areas.

Chomel is the granddaughter of Ah Meng, the Sumatran orangutan who spent more than four decades at Singapore Zoo and became one of its most iconic residents. Ayaan’s birth extends that family line and continues an important legacy in Singapore Zoo. Ayaan has been adopted by SMRT, whose support contributes to his care and the broader conservation efforts by Mandai Wildlife Group.

Sumatran orangutans are listed as Critically Endangered on the IUCN Red List, with wild populations continuing to decline due to habitat loss, the illegal pet trade and human-wildlife conflict. Managed populations in accredited zoos serve as an increasingly important genetic safety net for the species, and Ayaan’s birth represents a significant contribution to those long-term conservation efforts.