Do dogs have to get stuck together to become pregnant?

My question is does a male and female have to get stuck together to get pregnant?

uhm, no?

The canine male genital apparatus is made up of the testicles in the scrotum and the penis that is covered by a sheath of skin and only becomes visible when erect. When copulating the dog's penis engorges and this is why male and female dogs can be seen stand back to back after the act of copulation. Do not try to force them apart as this can cause internal injury to both sexes. Once the males penis losses its rigidity they will separate on their own.

The female canine's genital apparatus consists primarily of the ovaries, the uterus and the vagina

i dont think soo

Absolutely not: Only when the "sperm meets egg". And to get stuck the penis has to engorge -starting about one quarter away from the base of the penis on up near the tip. After the penetration the penis engorges until the part of the penis that’s pass the vagina entrance threshold continues to swell up, locking itself behind the smaller vagina opening. If you ever have the chance, take a look at how swollen the penis is three quarters of the length, and then gets smaller in girth or width right before the base.