Re: Doc. Not liking ecological breastfeeding for PP birth control.
Most people don't know that Ecological Breastfeeding (which takes 7 specific criteria, please read all 7 bullet points under "Ecological Breastfeeding" at this link).) is actually an option for a lot of women.
Of course, the level of hormones which suppress ovulation varies from woman to woman, but if you're following all 7 criteria to increase the chances of lactational amenorrhea, and you listen to your own body, you can definitely avoid pregnancy without barriers or pills.
It's 98-99% effective for the first 6 months. After that point, it really depends on the woman. If you have a history of success with the method (conceiving so late after the first child because of BFing amenorrhea), I don't see what the problem is with continuing.
Be firm with the doctor, remain self assured in your choices, and perhaps suggest the book Breastfeeding and Natural Child Spacing: How Ecological Breastfeeding Spaces Babies by Sheila K. Kippley. It's by no means a medical text or study, but having a reference might be valuable.
In any case, if you feel pressured again, find another doctor.
Hybrid Vigor - Strength From Diversity: Baby wearing, BFing, EC/IPTing, Cosleeping, Baby signing, Attachment parenting.