Chihuahua mating

Question
Hello! I'm new to this website and I hope you can help me out with this! But of course, I have to tell you a bit background about my Chihuahuas first then you can help me a little more.

I have a male Chihuahua whom is 2.4 years old at 3.2 lbs full grown. He is AKC registered. However, he was bred to 2 of my AKC female Chihuahuas which is 3.3 years old and 1.4 years old. Both are 4.2 lbs and 4.6 lbs full grown.

So he has tried to mate with 1.4 years old female when she was in her heat during on 9th day, 11th day & 13th day. He wasn't successfully in order to get "tied" together but I have seen him "made it inside of her private area" at many times. Even though, she wasn't aggressive and she was letting him to mate her. She was more like, "*Sighs* Lalala...hurry up do you mind?" You know? Lol. Anyway- his penis was inside at several times but is not LOCKED yet. They did it maybe 4-5 times during 9th, 11th and 13th days.

My question is...will she still get pregnant without being tied?

Now in the different story- he has successed by mating "tied/stuck" with 3.3 years old female during in her heat on 9th, 11th & 13th days. They were locked 3 times in between those dates. However, I came home from work and I saw that they are STILL mating then locked and it becomes more mating than 3 times. Maybe I'd guess from 9th day to now...in fact, they just got locked again yesterday! Even though, her private area has been less swollen now. I think she is finally telling him no more mating this time (today).

So my question is...What happened if they mated more often than 3 times during in her heat? The risk result is that she may have more puppies...more likely premature puppies?

I heard from someone saying that if a male has locked inside her and one sperm can goes in her one egg then next day, another sperm goes in her other egg then more after that. That is why I should have limited them by 3 ties only? Is that true?

Thank you!! :)

Answer
Hi Nataliya

First let me welcome you to the site!

So your younger female has a slim chance that she took.  The lock is Mother's Nature way of guarantee it, of course it's dependant on if she was ovulating.

The female dog reproductive mechanism is different from humans.  She releases her eggs and they take 7 days to mature, the sperm stays alive for up to 48 hours.

The female is born with all the eggs she is ever going to produce, and the male can produce millions, and millions of sperm in one go. So it's an old wives tale that the more you breed, the more pups you will have.   

The reason you limit the number of ties is because it's extremely exhausting for the male.  Sure he can produce more sperm but it takes at least 24 hours to replenish his body with good strong healthy sperm.  Repeated daily breedings and you are using the sperm that is weaker and less desirable.