Four years ago when we decided to start our family, we had a decision to make: we had an equally strong desire to adopt AND to have biological kids, so which one should we try for first? This was a question that we researched and asked others' opinions on.
The main reason that we chose to pursue adoption first was because we wanted adoption to be the priority, not an after thought. Many couples have several biological kids first, and then adopt later in life. This can make it seem like biological children are the priority, and adopted children as the after thought. I'm not saying that this is the intention of couples who go this route, but that it can at least be perceived this way.
Adopted kids need lots of attention at the beginning, which is important for bonding. Often times they have come from a traumatic situation and will need lots of extra patience and grace. If you have no other children in the home, you will be able to give them more love and attention and time for bonding.
If you pursue adoption first, you are not limited by having to make considerations for your biological or already adopted children. The children already in your home will usually limit the age of kids you can adopt, as well as the types of behaviors you are willing to bring into your home. This is a consideration we now have because of Esther: not only are we limited to only getting children younger than her (this is by personal choice after a lot of prayer and consideration) but we would probably have to say no to accepting a child with more extreme behaviors that we may have felt ok to handle before she was born.
If you are pursuing foster care adoption, it may also be easier to go this route first before having biological children because you don't have to worry about the impact of foster children coming and going through your home on your biological children.
With adoption, you are thrown into parenthood, oftentimes with a child who is older than a newborn, so you don't really get to figure it out from day one. It might be hard to know what to expect from a 13 months old if you haven't been there with them from day one (unless you have a lot of previous experience with kids). You may also be thrown in to dealing with behaviors that you have no idea how to react to. While these are difficulties, all parenting is a bit figure it out as you go, so I wouldn't say these things are deal breakers, just something to take into consideration.
If your first pregnancy occurs after you have adopted children in the home, you risk not knowing what to expect from your pregnant self. True, every pregnancy is different, so you never really know what to expect. But it may be difficult to be experiencing the ups and downs of your first pregnancy while you already have several kiddos underfoot. For the first 4 months of my pregnancy with Esther we had four kiddos in the home. While I did need extra help from Alex and my mom, we made it through just fine and I don't regret being pregnant at that time.
If you are close to or above 30 years of age, I personally wouldn't recommend adopting first. It gets harder and harder to get pregnant the older you get (plus the chance of birth defects gets higher). Also, carrying a pregnancy is harder with an older body. It makes more sense to start with trying to get pregnant if you are close to this age, especially if you want more than a couple biological children. This is especially true with certain kinds of adoption which may take many years to complete. I was 23 years old when we decided to start a family, so this wasn't an issue we took into consideration for ourselves.
Biological Kids First
Though we pursued adoption first, as I mentioned God did the unexpected and chose for our first child to be biological. Because we had a sense for what it would have been like to adopt before Esther came around, I am now glad that God chose for Esther to be our first. Although if it had happened the other way, I would probably be happy with that as well :)
Generally, the younger you are, the easier it is to conceive and carry a baby. Having biological kids first will allow you to use the most fertile years of your life towards pursuing this end. I would guess that this is the main reason most families pursue biological children before adopting.
Coming into a home where they already have brothers and sisters can be beneficial for adopted children. This gives them other playmates and helps them to learn more quickly what type of behavior is expected of members of this family.
If your biological children are a bit older when you pursue adoption, it is a great way to help them understand the gospel and God's love. Older children are usually very eager to help out with adopted children, and you can explain to them some of the unique needs that adopted children may come with.
If you are pursing a foster care adoption, there are rules and laws about many aspects of your parenting, some of which probably conflict with what you currently practice with your biological children. You will be questioned in depth about your parenting methods of your biological children. For example, we know a perfectly healthy family who had to go through parenting classes before they could pursue adoption because their social worker disagreed with some of their parenting practices. You also may have to treat your foster children different from your biological children until the adoption is finalized. For example, maybe you like to snuggle with your children in bed while reading them a bedtime story. This would not be allowed with a foster child, so either s/he would have to sit separate from the bed or you will need to find a new way to read bedtime stories at night. So, getting foster children after you already have biological children may disrupt some of your normal family patterns.
What has your family chosen? Have you pursed pregnancy or adoption first? What has your experience been like?