It's understood the Duchess has not been suffering morning sickness but has been exhausted after a gruelling schedule of back-to-back official engagements.
According to several royal correspondents - who posted the news on Twitter - Meghan is "feeling fine" but her team are trying to "pace things for her".
The Duchess of Sussex was due to join Prince Harry to support the Invictus Games cyclists but chose to "cut back" on her duties after a jam-packed start to the tour.
The royal couple wore matching black Invictus Games shirts.
Meghan joined Harry for later engagements on Sunday, with the couple attending a reception at the Pavilion Restaurant in the Domain for Invictus competitors, their families and friends hosted by Australian Prime Minister Scott Morrison.
Elecciones pospuestas en Kandahar tras ataque talibán
Unos 5.000 centros de votación tenían que habilitarse en la parte del país controlada por el gobierno. En la capital, acordonada, se prohibió la circulación de vehículos en la mayoría de las carreteras.
Prince Harry was without his pregnant wife as he presented medals to Invictus Games athletes on the sixth day of the couple's overseas trip.
QUEENSLAND royal watchers and fans have been left stunned by reports of a major change to the Duke and Duchess of Sussex's planned visit to Fraser Island.
The button-front midi was originally worn in white by Harry's ex last month, as she attended a polo match.
She is expected to scale back some of her engagements for the next couple of days as she and Harry head into the second week of their packed 16-day tour.
The Duke and Duchess of Sussex got plenty of parenting practice during the first week of their royal tour in Australia, mingling with dozens of young children Down Under. And we can't wait to see what else we learn about the new Duchess and her past.
Mr Alcott, who is a triple Paralympic gold medallist in wheelchair tennis and wheelchair basketball, said: "He [Harry] said: "Shall I put them on?'".