United Kingdom, July 16 -- Pete Davidson is to become a father for the first time.

The former Saturday Night Live star's girlfriend Elsie Hewitt has taken to Instagram to share pictures of the couple - who went public with their romance in March - showing off her growing bump and an ultrasound photo of the impending new arrival.

She quipped in the caption for the post: "Welp now everyone knows we had sex."

Sources told TMZ that Elsie is due to give birth in the winter and she and Pete recently shared their happy news with friends and family.

In May, the 29-year-old model gushed her boyfriend is the "best person" she's ever met.

She told People magazine: "He is so incredible. Honestly, best person I've ever met, and I'm so grateful .....