On a halachic level, there are many factors that could lead to permission to use birth control. For example, if you have at least one boy and one girl, that meets the Torah-level obligation to procreate. Factors such as finances, emotional readiness, and the couple's shalom bayit (marital harmony) could each provide grounds for using birth control, even when there are fewer than nine children. Additionally, the interpretations of the rabbinic admonitions to continue having children vary. For example, our site's supervising rabbi, Rav Yehuda Henkin, permits the use of birth control indefinitely when a couple already has at least two boys and two girls. For more details on the halachic factors, we direct you to our site's articles on "Permissibility" in the "Family Planning" section of our site.
Ultimately, this is a decision to make together. If you have difficulty discussing this with each other, and your husband objects to rabbinic counseling at this stage, you may find it helpful to see a counselor to facilitate your communication on this issue. Nefesh International, www.nefesh.org, provides referrals to religious therapists.
It is worth noting that contraceptive pills are not the only acceptable mode of birth control. In order to make an informed decision, we suggest you explore our site's articles on different methods, such as the IUD and the diaphragm, again in the "Family Planning" section of our site.
Please get back to us with any further questions.