My apologies to the OP. Please disregard my earlier, irrelevant, posts.
With regard to the fact that:
my husband is not okay with the idea but also has very logical and valid points on why he is against.
If your husband had only vague and emotional arguments against your having a child with your boyfriend, then there might be more room for discussion and a greater chance that he might come to terms with the idea over time. However, there are some very real ramifications that need to be addressed or agreed upon and if you are not on the same page...?
For instance, in many jurisdictions if a wife has a baby while married, then her husband is, for all intents and purposes, considered the father - regardless of whether his sperm were involved. This is termed the "presumption of paternity" (or "legitimacy"). In my own state:
...The presumption of paternity stands for the principle that “a child conceived or born during the marriage is presumed to be the child of the marriage.” The Pennsylvania Supreme Court maintains that the presumption of paternity is “one of the strongest presumptions of the law of Pennsylvania”...
If boyfriend flakes and takes off, your husband would be legally and financially responsible for a child that he neither desired nor helped create - that could be a major stumbling block for many people.