Sarah Stage, a 30-year-old lingerie model from Los Angeles, has named her newborn son James Hunter. He was born on Tuesday 14 April and measured 22 inches long.
Just one day before giving birth Stage shared the photo below showing her extremely toned bump:
Stage told E! News: "He's a big healthy boy and he got an APGAR score of 8-9. Thank you for supporting me throughout my pregnancy!"
The APGAR score is a quick assessment of a baby's health at birth. A score between eight and 10 means the baby is in good condition and only needs routine care.
Stone documented her pregnancy with a series of bump photos on Instagram, including the one below of her at 35 weeks with a friend who was 39 weeks pregnant.
Stage's slim appearance, even at nine months pregnant, attracted a lot of comments on Instagram.
Some expressed envy at Stage's toned figure, with one user writing: "How is this possible? I wish I looked like this when I was pregnant."
Stage responded to the criticism in a measured manner, posting a loaded quote on Instagram:
Stage previously told news.com.au she stayed in shape throughout her pregnancy by doing “light prenatal training", including Pilates, and by using a food delivery service to get "healthy meals" delivered to her door.
Geeta Nargund, medical director at Create Fertility, previously spoke to HuffPost UK Lifestyle about the risks of exercising while pregnant.
She said that moderate exercise in pregnancy "can help to reduce the risk of thromboembolism (clotting problems) and increase maternal circulation. But [a pregnant woman] should not continue to exercise if she feels tired or breathless."
"Excessive maternal exercise is not good for the baby because it may divert blood flow away from the placenta. Good placental circulation is necessary for normal fetal development."